TY - JOUR A1 - Rose, Kathleen M. A1 - Szopa, Jan A1 - Han, Fu-Sheng A1 - Cheng, Yung-Chi A1 - Richter, Arndt A1 - Scheer, Ulrich T1 - Association of DNA topoisomerase I and RNA polymerase I: A possible role for topoisomerase I in ribosomal gene transcription N2 - RNA polymerase I preparations purified from a rat hepatoma contained DNA topoisomerase activity. The DNA topoisomerase associated with the polymerase had an Mr of 110000, required Mg2+ but not ATP, and was recognized by anti-topoisomerase I antibodies. When added to RNA polymerase I preparations containing topoisomerase activity, anti-topoisomerase I antibodies were able to inhibit the DNA relaxing activity of the preparation as well as RNA synthesis in vitro. RNA polymerase II prepared by analogous procedures did not contain topoisomerase activity and was not recognized by the antibodies. The topoisomerase I: polymerase I complex was reversibly dissociated by column chromatography on Sephacryl S200 in the presence of 0.25 M (NH4hS04. Topoisomerase I was immunolocalized in the transcriptionally active ribosomal gene complex containing RNA polymerase I in situ. These data indicate that topoisomerase I and RNA polymerase I are tightly complexed both in vivo and in vitro, and suggest a role for DNA topoisomerase I in the transcription of ribosomal genes. Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33901 ER - TY - JOUR A1 - Reimer, Georg A1 - Raska, Ivan A1 - Scheer, Ulrich A1 - Tan, Eng M. T1 - Immunolocalization of 7-2-ribonucleoprotein in the granular component of the nucleolus N2 - Certain autoimmune sera contain antibodies against a nucleolar ribonucleoprotein particle associated with 7-2-RNA (R. Reddy et al. (1983) J. Bioi. Chem . 258, 1383; C. Hashimoto and J. A. Steitz (1983) J. Bioi. Chem. 258, 1379). In this study, we showed by immunofluorescence microscopy that antibodies reactive with 7-2-ribonucleoprotein immunolocalized in the granular regions of actinomycin D and 5,6-dichloro-I-j3-D-ribofuranosylbenzimidazole (DRB)-segregated nucleoli from Vero cells. By electron microscopic immunocytochemistry, antigen-antibody complexes were located in the granular component of transcriptionally active nucleoli from rat liver hepatocytes and HeLa cells. Anti-7- 2-RNP antibodies from two autoimmune sera immunoprecipitated a major protein of Mr 40,000 from e5S] methionine-Iabeled HeLa cell extract. The immunolocalization data suggest that 7-2-ribonucleoprotein may be involved in stages of ribosome biogenesis which take place in the granular component of the nucleolus, i.e., assembly, maturation, and/or transport of preribosomes Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33890 ER - TY - JOUR A1 - Benavente, Ricardo A1 - Schmidt-Zachmann, Marion S. A1 - Hügle-Dörr, B. A1 - Reimer, G. A1 - Rose, K. M. A1 - Scheer, Ulrich T1 - Identification and definition of nucleolus-related fibrillar bodies in micronucleated cells N2 - Small nucleolus-related bodies which occur in the nUcleoplasm of " micronuclei" lacking nucleolar organizers have been studied by immunofluorescence microscopy. These bodies stained specifically with three different antibodies directed against proteins that are normally associated with the dense fibrillar component of functional nucleoli, but not with antibodies specific for certain proteins of the granular component or the fibrillar centers. Our data show that, in the absence of rRNA genes, the various constituent proteins characteristic of the dense fibrillar component spontaneously assemble into spherical entities but that the subsequent fusion of these bodies into larger structures is prevented in these micronuclei. The similarity between these nucleolus-related bodies of micronuclei and the prenucleolar bodies characteristic of early stages of nucleologenesis during mitotic telophase is discussed. Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39423 ER - TY - JOUR A1 - Thiry, Marc A1 - Scheer, Ulrich A1 - Goessens, Guy T1 - Localization of DNA within Ehrlich tumour cells nucleoli by immunoelectron microscopy N2 - The distribution of DNA in Ehrlich tumour cell nucleoli was investigated by means of an immunocytochemical approach , involving a monoclonal antibody directed against double- and single-stranded DNA. Immunolabelling was performed . either before or after the embedding process. The postembedding labelling method allows better ultrastructural preservation than the preembedding labelling method. In particular, the various nucleolar components are well preserved and identifiable. In the nucleolus, labelling is particularly concentrated over the perinucleolar chromatin and over its intranucleolar invaginations, which penetrate the nucleolar body and often terminate at the fibrillar centres. In addition, aggregates of gold particles are found in the fibrillar centres, preferentially towards the peripheral regions. By contrast, the dense fibrillar component is completely devoid of labelling. The results seem to indicate that DNA containing the rDNA genes is located in the fibrillar centres, with a preference for the peripheral regions. This finding suggests that transcription of the rDNA genes should occur within the confines of the fibrillar centre, probably close to the boundary region of the surrounding dense fibrillar component. The results are discussed in the light of present knowledge of the functional organization of the nucleolus. KW - nucleolus KW - DNA KW - monoclonal antibody Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39327 ER - TY - JOUR A1 - Geise, W. A1 - Linsenmair, Karl Eduard T1 - Adaptations of the reed frog Hyperbolius viridiflavus to its arid environment. IV. Ecological significance of water economy with comments on thermoregulation and energy allocation N2 - No abstract available Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30570 ER - TY - JOUR A1 - Dabauvalle, Marie-Christine A1 - Schulz, Barbara A1 - Scheer, Ulrich A1 - Peters, Reiner T1 - Inhibition of nuclear accumulation of karyophilic proteins in living cells by microinjection of the lectin wheat germ agglutinin N2 - No abstract available Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34288 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Dabauvalle, Marie-Christine A1 - Merkert, Hilde A1 - Benavente, Ricardo T1 - The nuclear envelope and the organization of the pore complexes N2 - No abstract available Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34275 ER - TY - JOUR A1 - Linsenmair, Karl Eduard A1 - Schmuck, R. T1 - Adaptations of the reed frog Hyperbolius viridiflavus to its arid environment. III. Aspects of nitrogen metabolism and osmuregulation in the reed frog, H. viridiflavus taeniatus, with special reference to the role of iridophores N2 - Reed frogs of the superspecies Hyperolius viridiflavus occur throughout the seasonally very dry and hot African savannas. Despite their small size (300-700 mg), estivating reed frogs do not avoid stressful conditions above ground by burrowing into the soil, but endure the inhospitable climate relatively unprotected, clinging to mostly dry grass sterns. They must have emcient mechanisms to enable them to survive e.g. very high temperatures, low relative hurnidities, and high solar radiation loads. Mechanisms must also have developed to prevent poisoning by the nitrogenous wastes that inevitably result from protein and nucleotide turnover. In contrast to fossorial amphibians, estivating reed frogs do not become torpid. Reduction in metabolism is therefore rather Iimited so that nitrogenous wastes accumulate faster in these frogs than in fossorial amphibians. This severely aggravates the osmotic problems caused by dehydration. During dry periods total plasma osmolarity greatly increases, mainly due to urea accumulation. Of the total urea accumulated over 42 days of experimental water deprivation, 30% was produced during the first 7 days. In the next 7 days rise in plasma urea content was negligible. This strong initial increase of urea is seen as a byproduct of elevated amino acid catabolism following the onset of dry conditions. Tbe rise in total plasma osmolarity due to urea accumulation, however, is not totally disadvantageous, but enables fast rehydration when water is available for very short periods only. Voiding of urine and feces eeases once evaporative water loss exceeds 10% of body weight. Tberefore, during continuous water deprivation, nitrogenous end products are not excreted. After 42 days of water deprivation, bladder fluid was substantially depleted, and urea coneentration in the remaining urine (up to 447 mM) was never greater than in plasma fluid. Feces voided at the end of the dry period after water uptake contained only small amounts of nitrogenous end products. DSF (dry season frogs) seemed not to be uricotelic. Instead, up to 35% of the total nitrogenous wastes produced over 42 days of water deprivation were deposited in an osmotically inert and nontoxic form in iridophore crystals. The increase in skin purine content averaged 150 µg/mg dry weight. If urea had been the only nitrogenous waste product during an estivation period of 42 days, lethal limits of total osmolarity (about 700 mOsm) would have been reached 10-14 days earlier. Thus iridophores are not only involved in colour change and in reducing heat load by radiation remission, but are also important in osmoregulation during dry periods. The seIective advantages of deposition of guanine rather than uric acid are discussed. KW - Biologie KW - Zoologie KW - Frosch KW - Hyperolius viridiflavus KW - Estivation KW - Osmoregulation KW - Nitrogen metabolism KW - lridophores Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78108 ER - TY - JOUR A1 - Schmuck, R. A1 - Kobelt, F. A1 - Linsenmair, Karl Eduard T1 - Adaptations of the reed frog Hyperbolius viridiflavus (Anura, Hyperbolidae) to its arid environment: V. Iridophores and nitrogen metabolism N2 - Ofall amphibians living in arid habitats, reed frogs (belonging to the super species Hyperolius viridiflavus) are the most peculiar. Froglets are able to tolerate dry periods of up to 35 days or longer immediately after metamorphosis, in climatically exposed positions. They face similar problems to estivating juveniles, i.e. enduranee of long periods of high temperature and low RH with rather limited energy and water reserves. In addition, they must have had to develop meehanisms to prevent poisoning by nitrogenous wastes that rapidly accumulate during dry periods as a metabolie consequenee of maintaining a non-torpid state. During dry periods, plasma osmolarity of H. v. taeniatus froglets strongly increased, mainly through urea accumulation. Urea accumulation was also observed during metamorphic climax. During postmetamorphic growth, chromatophores develop with the density and morphology typical of the adult pigmentary pattern. The dermal iridophore layer, which is still incomplete at this time, is fully developed within 4-8 days after metamorphosis, irrespective of maintenance conditions. These iridophores mainly contain the purines guanine and hypoxanthine. The ability of these purines to reflect light provides an excellent basis for the role of iridophores in temperature regulation. In individuals experiencing dehydration stress, the initial rate of purine synthesis is doubled in eomparison to specimens continuously maintained under wet season conditions. This increase in synthesis rate leads to a rapid increase in the thiekness of the iridophore layer, thereby effectively reducing radiation absorption. Thus, the danger of overheating is diminished during periods of water shortage when evaporative cooling must be avoided. After the development of an iridophore layer of sufficient thickness for effective radiation reflectance, synthesis of iridophore pigments does not cease. Rather, this pathway is further used during the remaining dry season for solving osmotic problems eaused by accumulation of nitrogenous wastes. During prolonged water deprivation, in spite of reduced metabolic rates, purine pigments are produced at the same rate as in wet season conditions. This leads to a higher relative proportion of nitrogen end products being stored in skin pigments under dry season conditions. At the end of an experimental dry season lasting 35 days, up to 38% of the accrued nitrogen is stored in the form of osmotically inactive purines in thc skin. Thus the osmotic problems caused by evaporative water loss and urea production are greatly reduced. KW - Biologie KW - Zoologie KW - Frosch Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78094 ER - TY - JOUR A1 - Mäueler, Winfried A1 - Raulf, Friedrich A1 - Schartl, Manfred T1 - Expression of proto-oncogenes in embryonic, adult, and transformed tissue of Xiphophorus (Teleostei: Poeciliidae) N2 - In Xiphophorus the causative, primary cellular oncogene for melanoma formation has been assigned by classical genetics to a sex-chromosomal locus, designated Tu. Activation of Tu was proposed to be the result of the elimination of Tu-specific regulatory genes which normally suppress the transforming function in the nontumorous state. In order to understand the role which known proto-oncogenes migbt play in this process, we have analysed the expression of src, erb A, erb B, ras, abl, sis and mil related genes from Xiphophorus during embryogenesis, in non-tumorous organs and in melanoma cells. For src, ras, erb B and sis a differential expression during embryogenesis and/or in normal organs was detected, with preferential expression of src in neural tissues, a high abundance of sis transcripts in an embryonal epitheloid cellline and of erbB transcripts in the head nephros. In melanoma cells ras, src and a v-erb B related gene were found to be expressed. The src gene most likely is more involved in secondary processes during tumor progression, while the expression of the v-erb B related gene might be transformation-specific because recently such a sequence was found to map to the close vicinity of the Tu-locus. KW - Schwertkärpfling KW - Protoonkogen KW - Gewebe Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86233 ER - TY - JOUR A1 - Maueler, W. A1 - Barnekow, A. A1 - Eigenbrodt, E. A1 - Raulf, F. A1 - Falk, H. F. A1 - Telling, A. A1 - Schartl, Manfred T1 - Different regulation of oncogene expression in tumor and embryonal cells of Xiphophorus N2 - Melanoma formation in the poeciliid fish Xiphophorus is mediated primarily by a cellular oncogene, designated Tu. Elimination of Tu-specific genes releases the transforming function of Tu and leads to melanoma formation. Southern blot analyses revealed a tight linkage of a v-erb B related gene to the Tu-locus and Northern blot analyses of RNA of solid melanomas indicated a coordinated deregulation and for mutational activation of several oncogenes. In order to get a better insight into the regulation of oncogene expression in normal and transformed cells of Xiphophorus, we studied the expression of Xsrc, Xras, Xmyc, Xerb A, Xsis, and the v-erb B related gene in a melanoma derived cell line (PSM) and an embryonic cell line (A2) under conditions of low growth factor supply. Both celllines express the Xsrc, Xmyc, and Xras genes, while PSM cells in addition express the v-erb B related gene and A2 cells the Xsis gene. In PSM cells serum deprivation leads to an accumulation of most of the oncogene mRNAs analysed. This is most apparent for a 5.0 kb transcript of the v-erb B related gene, probably due to an increase in transcript stability. The levels of these mRNAs returned to normal within 2h after stimulation with 10% fetal calf serum. At the protein level we observed an initial decrease followed by an increase of the n-p60c-src kinase (the protein product of tbe Xsrc gene) activity in cells deprived of serum. Serum stimulation restored a normal pp60"-src kinase activity. In contrast serum deprivation of A2 cells reduced the transcript amounts of each of the oncogenes analysed. The same holds true for one beta-tubulin transcript, while the level of a second beta-tubulin transcript was unaffected. Serum stimulation led to a reactivation of Xras and Xsrc after a delay of approximately 48b. The pp60(c-src) kinase activity was found to be 6-10 times lower as compared to the PSM cells and did not differ between serum deprived and serum stimulated cells. Enzyme activities and isoenzyme patterns of several glycolytic enzymes were found to be not affected by serum deprivation and stimulation in both celllines. KW - Schwertkärpfling KW - Tumorzelle Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86240 ER - TY - JOUR A1 - Benavente, Ricardo A1 - Reimer, Georg A1 - Rose, Kathleen M. A1 - Hügle-Dörr, Barbara A1 - Scheer, Ulrich T1 - Nucleolar changes after microinjection of antibodies to RNA polymerase I into the nucleus of mammalian cells N2 - After microinjection of antibodies against RNA polymerase I into the nuclei of cultured rat kangaroo (PtKz) and rat (RVF-SMC) cells alterations in nucleolar structure and composition were observed. These were detected by electron microscopy and double-label immunofluorescence microscopy using antibodies to proteins representative of the three major components of the nucleolus. The microinjected antibodies produced a progressive loss of the material of the dense fibrillar component (DFC) from the nucleoli which, at 4 h after injection, were transformed into bodies with purely granular component (GC) structure with attached fibrillar centers (FCs). Concomitantly, numerous extranucleolar aggregates appeared in the nucleoplasm which morphologically resembled fragments of the DFC and contained a protein (fibrillarin) diagnostic for this nucleolar structure. These observations indicate that the topological distribution of the material constituting the DFC can be experimentally influenced in interphase cells, apparently by modulating the transcriptional activity of the rRNA genes. These effects are different from nucleolar lesions induced by inhibitory drugs such as actinomycin D-dependent "nucleolar segregation". The structural alterations induced by antibodies to RNA polymerase I resemble, however, the initial events of nucleolar disintegration during mitotic prophase. Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40666 ER - TY - CHAP A1 - Schartl, Manfred A1 - Mäueler, Winfried A1 - Raulf, Friedrich A1 - Robertson, Scott M. T1 - Molecular aspects of melanoma formation in Xiphophorus N2 - No abstract available. KW - Schwertkärpfling KW - Krebs Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72689 ER - TY - JOUR A1 - Raulf, F. A1 - Robertson, S. M. A1 - Schartl, Manfred T1 - Evolution of the neuron-specific alternative splicing product of the c-src proto-oncogene N2 - The observation of a slower migrating form of pp6oc-src in neural tissue of chicken and mouse has recently been shown to be due to an alternative transcript form of tbe c-src gene (Martinez et al.: Science 237:411-415, 1987; Levy et al.: Mol Cell Bio17:4142- 4145, 1987). An insertion of 18 basepairs between exons 3 and 4, presumed to be due to alternative splicing of a mini-exon, gives rise to six amino acid residues not found in the non-neuronal (termed flbroblastic) form of pp60\(^{c-src}\). Wehave addressed the question of the evolutionary origin of the c-src neuronal insert · and its functional signiflcance regarding neural-speciflc expression of the c-src gene. To this end we have investigated whether the c-src gene of a lower verlebrate (the teleost fish Xiphophorus) gives rise to a neural-specific transcript in an analogous manner. We could show that the fish c-src gene does encode for a "fibroblastic" and a "neuronal" form of transcript and that the neuronal transcript does indeed arise by way of alternative splicing of a mini-exon. The miniexon is also 18 basepairs long and we could demoostrate directly that this exon lies within the intron separating exons 3 and 4. For comparative purposes we have examined whether the fish c-yes gene, the member of the src gene family most closely related to c-src, also encodes a neural tissue-specific transcript. No evidence for a second transcript form in brain was obtained. This result suggests that the mini-exon arose within the c-src gene lineage sometime between the srclyes gene duplication event and the divergence of the evolutionary lineage giving rise to the teleost fish. Published genomic sequence of src-related genes in Drosophila and our own results with Hydra demoostrate no intron in these species at the analogous location, consistent with first appearance of this mini-exon sometime between 550 and 400 million years ago. KW - Physiologische Chemie KW - Xiphophorus KW - teleost flsh KW - polymerase KW - chain reaction KW - RT -PCR KW - mini-exon KW - pp6oc-src Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61796 ER - TY - JOUR A1 - Wittbrodt, J. A1 - Adam, D. A1 - Malitschek, B. A1 - Maueler, W. A1 - Raulf, F. A1 - Telling, A. A1 - Robertson, M. A1 - Schartl, Manfred T1 - Novel putative receptor tyrosine kinase encoded by the melanoma-inducing Tu locus in Xiphophorus N2 - No abstract available KW - Physiologische Chemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61800 ER - TY - JOUR A1 - Bernards, R. A1 - Schackleford, G. M. A1 - Gerber, M. R. A1 - Horowitz, J. M. A1 - Friend, S. H. A1 - Schartl, Manfred A1 - Bogenmann, E. A1 - Rapaport, J. M. A1 - Mcgee, T. A1 - Dryja, T. P. T1 - Structure and expression of the murine retinoblastoma gene and characterization of its encoded protein N2 - No abstract available KW - Physiologische Chemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61819 ER - TY - JOUR A1 - Weigel, U. A1 - Meyer, M. A1 - Sebald, Walter T1 - Mutant proteins of human interleukin 2. Renaturation yield, proliferative activity and receptor binding N2 - No abstract available KW - Biochemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62543 ER - TY - JOUR A1 - Flügge, U. I. A1 - Fischer, K. A1 - Gross, A. A1 - Sebald, Walter A1 - Lottspeich, F. A1 - Eckerskorn, C. T1 - The triose phosphate-3-phosphoglycerate-phosphate translocator from spinach chloroplasts: nucleotide sequence of a full-length cDNA clone and import of the in vitro synthesized precursor protein into chloroplasts N2 - No abstract available KW - Biochemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62559 ER - TY - JOUR A1 - Kreft, Jürgen A1 - Funke, D. A1 - Schlesinger, R. A1 - Lottspeich, F. A1 - Goebel, Werner T1 - Purification and characterization of cytolysins from Listeria monocytogenes serovar 4b and Listeria ivanovii N2 - Several exoproteins from Listeria monocytogenes serovar 4b (NCTC 10527) and Listeria ivanovii (ATCC) 19119, SLCC 2379), respectively, have been purified to homogeneity by thiol-disulfide exchange chromatography and gel filtration. Both strains produce a haemolytic/cytolytic protein of Mr 58 kDa, which has all the properties of a SH-activated cytolysin, the prototype of which is streptolysin 0 (SLO), and this protein has therefore heen termed Iisteriolysin 0 (LLO). In addition a protein of Mr 24 kDa from culture supernatants of L. ivanovii co-purified withLLO. The N-terminal aminoacid sequences of both proteins from L. ivanovii have been determined. By mutagenesis with transposons of Gram-positive origin (Tn916 and TnI545), which have been introduced via conjugation into L. ivanovii, several phenotypic mutants (altered haemolysis on sheep blood agar or lecithinase-negative) were obtained. Results on the properties of these muntants will he presented. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47036 ER - TY - JOUR A1 - Kreft, Jürgen A1 - Haas, Albert A1 - Goebel, Werner T1 - Isolation and characterization of genes coding for proteins involved in the cytolysis by Listeria ivanovii N2 - We established a library of chromosomal DNA of Listeria ivanovii in the pTZ19R plasmid system, using Escherichia coli DH5alpha as the host. One recombinant clone reacted strongly with a polyclonal antiserum raised against the listeriolysin 0 and a second exoprotein (24kDa) of L. ivanovii, which is most probably also involved in cytolytic processes. The recombinant E. coli clone may contain part of the listeriolysin 0 gene of L. ivanovii. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46991 ER - TY - JOUR A1 - Gessler, Manfred A1 - Bruns, G. A. P. T1 - A physical map around the WAGR complex on the short arm of chromosome 11 N2 - A long-range restriction map of part of the short arm of ehromosome 11 including the WAGR region has been constructed using pulsed-field gel electrophoresis and a number of infrequently cutting restriction enzymes. A total of 15.4 Mbp has been mapped in detall, extending from proximal 11p14 to the distal part of 11p12. The map localizes 35 different DNA probes and reveals at least nine areas with features eharaeteristle of BTF islands, some of which may be candidates for the different loci underlying the phenotype of the WAGR syndrome. This map will furthermore allow screening of DNA from individuals with WAGR-related phenotypes and from Wilms tumors for associated chromosomal rearrangements. KW - Biochemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59246 ER - TY - JOUR A1 - Gessler, Manfred A1 - Thomas, G. H. A1 - Couillin, P. A1 - Junien, C. A1 - McGillivray, B. C. A1 - Hayden, M. A1 - Jaschek, G. A1 - Bruns, G. A. T1 - A deletion map of the WAGR region on chromosome II N2 - The WAGR (Wilms tumor, aniridia, genitourinary anomalies, and mental retardation) region has been assigned to chromosome 11p13 on the basis of overlapping constitutional deletions found in affected individuals. We have utilized 31 DNA probes which map to the WAGR deletion region, together with six reference loci and 13 WAGR-related deletions, to subdivide this area into 16 intervals. Specific intervals have been correlated with phenotypic features, leading to the identification of individual subregions for the aniridia and Wilms tumor loci. Delineation, by specific probes, of multiple intervals above and below the critical region and of five intervals within the overlap area provides a framework map for molecular characterization of WAGR gene loci and of deletion boundary regions. KW - Biochemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59255 ER - TY - JOUR A1 - Kreft, Jürgen A1 - Funke, Dorothee A1 - Haas, Albert A1 - Lottspeich, Friedrich A1 - Goebel, Werner T1 - Production, purification and characterization of hemolysins from Listeria ivanovii and Listeria monocytogenes Sv4b. N2 - In culture supematants of both Listeria ivanovii and Listeria monocytogenes Sv4b, for the first time a hemolysin of molecular weight 58 kDa was identified, which had all the characteristics of an SH-activated cytolysin, and which was therefore identified as Iisteriolysin 0 (LLO). In the case of L. ivanovii a second major supematant protein of molecular weight 24 kDa co-purified with LLO. However, the function of this protein has to be determined. In culture supematants of L. ivanovii a sphingomyelinase and a Iecithinase activity could be detected, both enzymatic activities together contributing to the pronounced hemolysis caused by L. ivanovii. The N-tenninal amino acid sequences of LLO and the 24 kDa from L. ivanovii are shown. KW - Biologie KW - Hemolysin KW - Listeria Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60545 ER - TY - JOUR A1 - Gilmore, Michael S. A1 - Cruz-Rodz, Armando L. A1 - Leimeister-Wächter, Michaela A1 - Kreft, Jürgen A1 - Goebel, Werner T1 - A Bacillus cereus cytolytic determinant, cereolysin AB, which comprises the phospholipase C and sphingomyelinase genes: nucleotide sequence and genetic linkage N2 - A cloned cytolytic determinant from the genome of Bacillus cereus GP-4 has been characterized at the molecular Ievel. Nucleotide sequence determination revealed the presence of two open reading frames. 8oth open reading frames were found by deletion and complementation analysis to be necessary for expression of the hemolytic phenotype by Bacillus subtilis and Escherichia coli hosts. The 5' open reading frame was found to be nearly identical to a recently reported phospholipase C gene derived from a mutant B. cereus strain which overexpresses the respective protein, and it conferred a lecithinase-positive phenotype to the B. subtilis host. The 3' open reading frame encoded a sphingomyelinase. The two tandemly encoded activities, phospholipase C and sphingomyelinase, constitute a biologically functional cytolytic determinant of B. cereus termed cereolysin AB. KW - Biologie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60588 ER - TY - JOUR A1 - Benavente, Ricardo A1 - Dabauvalle, Marie-Christine A1 - Scheer, Ulrich A1 - Chaly, Nathalie T1 - Functional role of newly formed pore complexes in postmitotic nuclear reorganization N2 - Many nuclear proteins are released into the cytoplasm at prometaphase and are transported back into the daughter nuclei at the end of mitosis. To determine the role of this reentry in nuclear remodelling during early interphase, we experimentally manipulated nuclear protein uptake in dividing cells. Recently we and others have shown that signal-dependent, pore complex-mediated uptake of nuclear protein is blocked in living cells on microinjection of the lectin wheat germ agglutinin (WGA), or of antibodies such as PI1 that are directed against WGA-binding pore complex glycoproteins. In the present study, we microinjected mitotic PtKz cells with WGA or antibody PIt and followed nuclear reorganization of the daughter cells by immunofluorescence and electron microscopy. The inhibitory effect on nuclear protein uptake was monitored by co-injection of the karyophilic protein nucleoplasmin. When injected by itself early in mitosis, nucleoplasmin became sequestered into the daughter nuclei as they entered telophase. In contrast, nucleoplasmin was excluded from the daughter nuclei in the presence of WGA or antibody PI1 . Although PtKz cells with blocked nuclear protein uptake completed cytokinesis, their nuclei showed a telophaselike organization characterized by highly condensed chromatin surrounded by a nuclear envelope containing a few pore complexes. These findings suggest that pore complexes become functional as early as telophase, in close coincidence with nuclear envelope reformation. They further indicate that the extensive structural rearrangement of the nucleus during the telophase-G1 transition is dependent on the influx of karyophilic proteins from the cytoplasm through the pore complexes, and is not due solely to chromosome- associated components. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40754 ER - TY - JOUR A1 - Weber, Thomas A1 - Schmidt, Erwin A1 - Scheer, Ulrich T1 - Mapping of transcription units on Xenopus laevis lampbrush chromosomes by in situ hybridization with biotin-labeled cDNA probes N2 - A non-radioactive in situ hybridization method is described for the localization of transcription units of defined genes to lateral loops of Xenopus laevis lampbrush chromosomes. Two Xenopus cONA probes were used encoding the nucleolar protein N038/ B23 and cytokeratin 1(8). Both proteins are known to be synthesized in Xenopus oocytes, and Northern blot analysis revealed the presence of the corresponding mRNAs in different oogenic stages. The probes were enzymatically labeled with biotin-dCTP and hybridized to lampbrush chromosomes. The sites of hybridization were detected either by indirect immunofluorescence microscopy using rabbit antibodies against biotin and fluorescein-conjugated antirabbit IgG or enzymatically using peroxidase-conjugated streptavi din. The probe encoding the nucleolar protein hybridized to two sets of lateral loops on different bivalents, the cytokeratin probe to at least four. Our finding that each probe hybridized to more than one chromosomal locus may reflect the tetraploid nature of the Xenopus laevis genome or results from cross-hybridization to other transcriptionally active members of the N038/ B23-nucleoplasmin or the cytokeratin-Iamin gene families. The method described should facilitate further in situ hybridization studies with appropriate genomic clones in order to map specific DNA sequences to defined loop regions and to come to a better understanding of the relationship between loop organization and gene transcription unit. KW - Cytologie KW - Lampbrush chromosomes KW - in situ hybridization KW - transcription units KW - Xenopus oocytes Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40763 ER - TY - JOUR A1 - Benavente, Ricardo A1 - Scheer, Ulrich A1 - Chaly, Nathalie T1 - Nucleocytoplasmic sorting of macromolecules following mitosis: fate of nuclear constituents after inhibition of pore complex function N2 - PtK2 cells in which pore complex-mediated transport is blocked by microinjection early in mitosis of a monoclonal antibody (specific for an Mr 68000 pore complex glycoprotein) or of wheat germ agglutinin (WGA) complete cytokinesis. However, their nuclei remain stably arrested in a telophase-like organization characterized by highly condensed chromatin and the absence of nucleoli, indicating a requirement for pore-mediated transport for the reassembly of interphase nuclei. We have now examined this requirement more closely by monitoring the behavior of individual nuclear macromolecules in microinjected cells using immunofluorescence microscopy and have investigated the effect of microinjecting the antibody or WGA on cellular ultrastructure. The absence of nuclear transport did not affect the sequestration into daughter nuclei of components such as DNA, DNA topoisomerase I and the nucleolar protein fibrillarin that are carried through mitosis on chromosomes. On the other hand, lamins, snRNAs and the p68 pore complex glycoprotein, all cytoplasmic during mitosis, remained largely cytoplasmic in the telophase-arrested cells. Electron microscopy showed the nuclei to be surrounded by a doublelayered membrane with some inserted pore complexes. In addition, however, a variety of membranous structures with associated pore complexes was regularly noted in the cytoplasm, suggesting that chromatin may not be essential for the postmitotic formation of pore complexes. We propose that cellular compartmentalization at telophase is a two-step process. First, a nuclear envelope tightly encloses the condensed chromosomes, excluding non-selectively all macromolecules not associated with the chromosomes. Interphase nuclear organization is then progressively restored by selective pore complex-mediated uptake of nuclear proteins from the cytoplasm. KW - Cytologie KW - Nucleocytoplasmic transport KW - nuclear organization KW - nuclear envelope KW - nucleologenesis KW - mitosis Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40777 ER - TY - JOUR A1 - Maschwitz, Ulich A1 - Fiala, Brigitte A1 - Lee, Ying Fah A1 - Chey, Vun Khen A1 - Tan, Fui Lian T1 - New and little-known myrmecophytic associations from Bornean rain forests N2 - The woody climber Millettia niuewenhuisii (Fabaceae) and the shrub Myrmeconauclea strigosa (Rubiaceae) in Sabah, Borneo are associated with ants. The hollow stems of Millettia nieuwenhuisii are regularly inhabited by an aggressive Cladomyrma sp., which keeps pseudococcids inside the stem. On Myrmeconauclea strigosa the ants live in hollow internodal swellings near the end of the branches. In this plant many different ant species use the nesting space in an opportunistic manner. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42957 ER - TY - JOUR A1 - Fiala, Brigitte A1 - Maschwitz, Ulrich A1 - Pong, Tho, Yow A1 - Helbig, Andreas J. T1 - Studies of a South East Asian ant-plant association : protection of Macaranga trees by Crematogaster borneensis N2 - In the humid tropics of SE Asia there are some 14 myrmecophytic species of the pioneer tree genus Macaranga (Euphorbiaceae). In Peninsular Malaysia a close association exists between the trees and the small, non-stinging myrmicine Crema togas ter borneensis. These ants feed mainly on food bodies provided by the plants and have their colonies inside the hollow intemodes. In a ten months field study we were able to demonstrate for four Macaranga species (M. triloba, M. hypoleuca, M. hosei, M. hulletti) that host plants also benefit considerably from ant-occupation. Ants do not contribute to the nutrient demands of their host plant, they do, however, protect it against herbivores and plant competition. Cleaning behaviour of the ants results in the removal of potential herbivores already in their earliest developmental stages. Strong aggressiveness and a mass recruiting system enable the ants to defend the host plant against many herbivorous insects. This results in a significant decrease in leaf damage due to herbivores on ant-occupied compared to ant-free myrmecophytes as well as compared to non-myrmecophytic Macaranga species. Most important is the ants' defense of the host plant against plant competitors, especially vines, which are abundant in the well-lit pioneer habitats where Macaranga grows. Ants bite off any foreign plant part coming into contact with their host plant. Both ant-free myrmecophytes and non-myrmecophytic Macaranga species had a significantly higher incidence of vine growth than specimens with active ant colonies. This may be a factor of considerable importance allowing Macaranga plants to grow at sites of strongest competition. KW - Ant/plant interaction KW - Myrmecophytes KW - Protection KW - Macaranga KW - Crematogaster borneensis Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42857 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Ribes, V. A1 - Tollervey, David T1 - Schizosaccharomyces pombe U4 small nuclear RNA closely resembles vertebrate U4 and is required for growth N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29771 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Tollervey, David T1 - Cloning of Schizosaccharomyces pombe genes encoding the U1,U2,U3 and U4 snRNAs N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29919 ER - TY - RPRT A1 - Gessler, Manfred A1 - Simola, Kalle O. A1 - Bruns, Gail A. P. T1 - Cloning of breakpoints of a chromosome translocation identifies the AN2 locus N2 - Chromosome translocations involving llpl3 have been associated with familial aniridia in two kindreds highlighting the chromosomal localization of the AN2 locus. This locus is also part of the WAGR complex (Wilros tumor, aniridia, genitourinary abnormalities, and mental retardation). In one kindred, the translocation is associated with a deletion, and probes for this region were used to identify and clone the breakpoints of the translocation in the second kindred. Comparison of phage restriction maps exclude the presence of any sizable deletion in this case. Sequences at the chromosome 11 breakpoint are conserved in multiple species, suggesting that the translocation falls within the AN2 gene. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30177 ER - TY - JOUR A1 - Grafe, U. A1 - Linsenmair, Karl Eduard T1 - Protogynous sex change in the Reed Frog: Hyperolius viridiflavus N2 - Observations on captive reed frogs Hyperolius viridijlavus ommatostictus showed that seven out of 24 females changed into males. Sex change occurred without any hormone treatment and resulted in completely functional males. The adaptive value is discussed in terms of maximizing life-time reproductive success. Hyperolius r. ommatostictus is the first amphibian known to show functional sex reversal. Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30990 ER - TY - JOUR A1 - Raulf, Friedrich A1 - Mäueler, Winfried A1 - Robertson, Scott M. A1 - Schartl, Manfred T1 - Localization of cellular src mRNA during development and in the differentiated bipolar neurons of the adult neural retina in Xiphophorus N2 - The expression of the c-src gene in embryonie and adult tissue of the teleost fish Xiphophorus helleri was analyzed by in-situ hybridization. The highly conserved fish c-src gene was found to be expressed at high levels in midterm embryos, where c-src mRNA was localized in developing neurons of the sensory layer of the differentiating retina and in the developing brain. In adult tissues the expression of c-src was found to persist in certain cell types of the brain and the neural retina, especially in the bipolar cells of the inner nuclear layer, which are postmitotic, fully differentiated mature neurons. Thus c-src in Xiphophorus appears to be a developmentally regulated proto-oncogene which is important for neuronal differentiation during organogenesis, but whose persistence of expression in certain terminally differentiated neurons strongly suggests a particular maintenance function for c-src in these cells as well. KW - Schwertkärpfling KW - Messenger-RNS Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86703 ER - TY - JOUR A1 - Schartl, Manfred A1 - Holstein, Thomas A1 - Robertson, Scott M. A1 - Barnekow, Angelika T1 - Preferential expression of a pp60c-src related protein tyrosine kinase activity in nerve cells of the early metazoan Hydra (Coelenterates) N2 - It has been suggested that the proto-oncogene c-src plays a functional role in developing neurons, and in the mature nerve cells of higher vertebrales. The coelenterate Hydra represents tbe most primitive known organism possessing nerve cells. With Southern blot hybridizations we have demonstrated src-related sequences in Hydra. Antisera specific for the c-src gene product (pp60 c-src) of birds and mammals precipitate a protein from Hydra cell extracts with a tyrosine-specific protein kinase activity. Studies of tissues and cells fractionated from a temperature sensitive mutant of Hydra which is depleted of interstitial (including nerve) cells at tbe non-permissive temperature, have indicated the src-like kinase of Hydra to be preferentially expressed in nerve cells. The high conservation of structural features and of the expression pattern indicates a basic function for pp60c-src in neurons. KW - Protein-Tyrosin-Kinasen KW - Nervenzelle KW - Süßwasserpolypen Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86179 ER - TY - JOUR A1 - Merz, H. A1 - Fliedner, A. A1 - Lehrnbecher, T. A1 - Sebald, Walter A1 - Müller-Hermelink, H. K. A1 - Feller, A. C. T1 - Cytokine expression in B-cell non-Hodgkin lymphomas N2 - No abstract available KW - Biochemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62539 ER - TY - JOUR A1 - Fiala, Brigitte T1 - Extrafloral nectaries versus ant-Homoptera mutualisms : a comment on Becerra and Venable N2 - No abstract available KW - Nektarium KW - Ameise Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32948 ER - TY - JOUR A1 - Schartl, Manfred T1 - Homology of melanoma-inducing loci in the genus Xiphophorus N2 - Several species of the genus Xiphophorus are polymorphic for specific pigment patterns. Same of these give rise to malignant melanoma following the appropriate crossings. For one of these pattern Iod from the platyfish Xiphophorus maculatus the melanoma-inducing gene has been doned and found to encode a novel receptor tyrosine kinase, designated Xmrk. Using molecular probes from this gene in Southern blot analyses on single fish DNA preparations from 600 specimens of different populations of various species of the genus Xiphophorus and their hybrids, either with or without melanomapredisposing pattern, it was shown that all individuals contain the Xmrk gene as a proto-oncogene. It is located on the sex chromosome. All fish that carry a melanoma-predisposing locus which has been identified by Mendelian genetics contain an additional copy of Xmrk, closely linked to a specific melanophore pattern locus on the sex chromosome. The melanoma-inducing loci of the different species and populations are homologous. The additional copy of Xmrk obviously arose by a geneduplication event, thereby acquiring the oncogenic potential. The homology of the melanomainducing Iod points to a similar mechanism of tumor suppression in all feral fish populations of the different species of the genus Xiphophorus. KW - Physiologische Chemie KW - Xiphophorus Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61757 ER - TY - JOUR A1 - Dracopoli, Nicholas C. A1 - Feltquate, David M. A1 - Sam, Brigitta A1 - Schartl, Manfred T1 - Taql and Mspl RFLPs are detected by the human 2,3-biphosphoglycerate mutase (BPGM) cDNA N2 - No abstract available KW - Physiologische Chemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61763 ER - TY - JOUR A1 - Friedenreich, Hildegard A1 - Schartl, Manfred T1 - Transient expression directed by homologous and heterologous promoter and enhancer sequences in fish cells N2 - ln order to construct fish specific expression vectors for studies on gene regulation in vitro and in vivo a variety of heterologous enhancers and promoters from mammals and from viruses of higher vertebrate cells were tested for expression of the bacterial chloramphenicol acetyl transferase reporter gene in three teleost fish cell lines. Several viral enhancers were found to be constitutively active at high Ieveis. The human metallothionein promoter showed inducible expression in the presence of heavy metal Ions. A fish sequence was isolated that can be used as a homologous constitutively active promoter for expression of foreign genes. Using the human growth hormone gene with an active promoter in fish cells for transient expression insufficient splicing and Iack of translation were observed, pointing to limitations in the use of heterologous genes in gene transfer experiments. On the contrary, some heterologous promoters and enhancers functioned in fish c as weil as in their cell type of origin, indicating t at corresponding transcription factors are sufficient conserved between fish and human over a period of 900 million years of Independent evolution. KW - Physiologische Chemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61774 ER - TY - JOUR A1 - Clauss, Gerd A1 - Winkler, Christoph A1 - Lohmeyer, Jürgen A1 - Anders, Fritz A1 - Schartl, Manfred T1 - Oncofetal antigen in Xiphophorus detected by monoclonal antibodies directed against melanoma-associated antigens N2 - Monoclonal antlbodies (MAbs) directed against Xiphophorus melanoma cells were deve(oped and tested by lndirect immunofluorescence and Immunoperoxidase staining for reactivity with a panel of I 5 allogeneic tissues and 12 allogeneic cell llnes. The reactivity of such MAbs was restricted to melanoma cells from tumor biopsies and melanoma-derived cell lines. ln addition, all embryonie cells of all histiotypes from developmental stages later than mld·organogenesis and from corresponding short term in vitro cultures reacted with these MAbs. ln contrast, normal tissues and organs from adult fish dlsplayed no reactivity, thus implying that the melanoma-associated antigens detected by the MAbs described are oncofetal antigens. KW - Physiologische Chemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61784 ER - TY - JOUR A1 - Gessler, Manfred A1 - Hameister, H. A1 - Henry, I. A1 - Junien, C. A1 - Braun, T. A1 - Arnold, H. H. T1 - The human MyoD1 (MYF3) gene maps on the short arm of chromosome 11 but is not associated with the WAGR locus or the region for the Beckwith-Wiedemann syndrome N2 - The human gene encoding the myogenic determination factor myf3 (mouse MyoD1) has been mapped to the short arm of chromosome 11. Analysis of several somatic cell hybrids containing various derivatives with deletions or translocations revealed that the human MyoD (MYF3) gene is not associated with the WAGR locus at chromosomal band 11pl3 nor with the loss of the heterozygosity region at 11p15.5 related to the Beckwith-Wiedemann syndrome. Subregional mapping by in situ hybridization with an myf3 specific probe shows that the gene resides at the chromosomal band llp14, possibly at llp14.3. KW - Biochemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59221 ER - TY - JOUR A1 - van Heyningen, V. A1 - Bickmore, W. A. A1 - Seawright, A. A1 - Fletcher, J. M. A1 - Maule, J. A1 - Fekete, G. A1 - Gessler, Manfred A1 - Bruns, G. A. A1 - Huerre-Jeanpierre, C. A1 - Junien, C. T1 - Role for the Wilms tumor gene in genital development? N2 - No abstract available KW - Biochemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59238 ER - TY - JOUR A1 - Fiala, Brigitte A1 - Maschwitz, Ulrich T1 - Studies on the south east asian ant-plant association Crematogaster borneensis / Macaranga: adaptations of the ant partner. N2 - C. borneensis (Myrmicinae) lives in dose association with several myrmecophytic species of the South East Asian pioneer tree genus Macaranga (Euphorbiaceae). The ants are adapted to the plants so dosely that they do not survive away from it. The only food they utilize is provided as food bodies by the plant and honeydew from specific scale insects kept inside the hollow internodes. The anatomy of the digestive tract is also adapted to life on the host plant: the crop is very sm all and can store only minute food quantities. C. borneensis exdusively colonizes certain Macaranga species. Queens as weIl as workers are able to recognize their host plant species, probably by chemical cues. Colony founding queens swarm throughout the year, mostly during darkness. There is strong competition among queens for host plants. Queens do not carry scale insects on their nuptial flight. Worker ants are active day and night. Most of them patrol and collect food bodies on the younger parts of the host plant. An important characteristic is their deaning behaviour, which results in removal of aIl foreign objects. Even though they are rather smalI, workers respond very aggressively to certain kinds of disturbance of the host plant. The ants attack most phytophagous insects and are especially effective in killing and removing smalI, softbodied herbivores (e.g. caterpillars). They do not possess a functional sting, but apply defensive secretion and-once biting an intruder-will not let go. Their effective alarm system results in a mass attack, which provides adequate defence for the colony and the host plant. A comparison with another Crematogaster species further illustrated the special adaptations of C. borneensis to its host plant. N2 - Untersuchungen über die südostasiatische Ameisen·Pflanzen-Vergesellschaftung Cremattogaster borneensis Maoaranga : Anpassungen des Ameisenpartners 213 C. borneensis (Myrmicinae) lebt in enger Gemeinschaft mit myrmekophytischen Arten der südostasiatischen Pionierbaumgattung Macaranga (Euphorbiaceae) . Die Ameise ist so eng an die Pflanze adaptiert, daß sie getrennt von ihr nicht lebensfähig ist. Die Nahrung bezieht C. borneensis in Form von Nährkörperchen ausschließlich von der Pflanze. Im Sproßachseninnern gehaltene spezifische Schildläuse bieten eine weitere Nahrungsquelle. Die Adaptationen erstrecken sich bis auf die Anatomie des Verdauungstraktes : Der Kropf ist sehr klein und kann nur geringe Nahrungsmengen speichern. C. borneensis besiedelt spezifisch nur Macaranga-Pflanzen. Sowohl Königinnen als auch Arbeiterinnen sind in der Lage, die Wirtspflanze zu erkennen, wobei offenbar chemische Reize eine Rolle spielen. Die koloniegründenden Königinnen schwärmen das gesamte Jahr über, das Schwärmen erfolgt überwiegend während der Dunkelheit. Um die besiedlungsfähigen Macaranga-Pflanzen herrscht ein starker Konkurrenzdruck. Die beteiligten Schildlausarten sind spezifisch für die Assoziation. Sie werden nicht von der Königin beim Hochzeitsflug mitgenommen. Die Arbeiterinnen sind tag- und nachtaktiv. Die meisten Tiere halten sich im jüngsten Drittel der Pflanze auf, wo sie patrouillieren und Nährkörperchen sammeln. Mittels eines spezifischen Säuberungsverhaltens entfernen die Arbeiterinnen alle Fremdobjekte von der Pflanze. Trotz ihrer geringen Größe attackieren die Ameisen eine Vielzahl phytophager Insekten und sind dabei besonders effektiv in der Abwehr kleiner, wenig sklerotisierter Tiere wie z.B. Raupen. Sie verfügen zwar nicht ' über einen funktionsfähigen Stachel, setzen aber Wehrsekrete ein und beißen sich hartnäckig fest . Mit Hilfe eines effektiven Alarmierungssystems, das einen Massenangriff ermöglicht, gewährleisten sie eine Verteidigung ihrer Kolonien und damit gleichzeitig ihrer Wirtspflanze. Eine Vergleich mit einer anderen Crematogaster-Art demonstriert die besonderen Adaptationen von C. borneensis an ihre Wirtspflanze. Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32689 ER - TY - JOUR A1 - Weising, K. A1 - Fiala, Brigitte A1 - Ramloch, K. A1 - Kahl, K. A1 - Epplen, J. T. T1 - Olingonucleotide fingerprinting in angiosperms N2 - No abstract available Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42884 ER - TY - JOUR A1 - Dabauvalle, Marie-Christine A1 - Loos, Karin A1 - Scheer, Ulrich T1 - Identification of a soluble precursor complex essential for nuclear pore assembly in vitro N2 - No abstract available Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32801 ER - TY - JOUR A1 - Scheer, Ulrich A1 - Benavente, Ricardo T1 - Functional and dynamic aspects of the mammalian nucleolus N2 - Nucleoli are the sites of ribosome biogenesis. Transcription of the ribosomal RNA genes as well as processing and initial packaging of their transcripts with ribosomal and non-ribosomal proteins all occur within the nucleolus in an ordered manner and under defined topological conditions. Components of the nucleolus have been localized by immunocytochemistry and their functional aspects investigated by microinjection of antibodies directed against the enzyme responsible for rDNA transcription, RNA polymerase I. The role of nascent transcripts in postmitotic formation of nucleoli will be discussed. Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34269 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Sibbald, Peter R. T1 - Trans-splicing of pre-mRNA is predicted to occur in a wide range of organisms including vertebrates N2 - No abstract available Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29798 ER - TY - JOUR A1 - Gessler, Manfred A1 - Poustka, Annemarie A1 - Cavenee, Webster A1 - Neve, Rachael L. A1 - Orkin, Stuart H. A1 - Bruns, Gail A. T1 - Homozygous deletion in Wilms tumours of a zinc-finger gene identified by chromosome jumping N2 - No abstract available Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30122 ER - TY - JOUR A1 - Barnekow, Angelika A1 - Jahn, Reinhard A1 - Schartl, Manfred T1 - Synaptophysin: a substrate for the protein tyrosine kinase pp60c-src in intact synaptic vesicles N2 - Expression of pp60 c-src, the first well defined proto-oncogene product, is developmentally regulated and tissue-specific, with neuronal tissues displaying high amounts of the c-src encoded pp60 c-src kinase activity. In the central nervous system pp60 s-src is preferentially expressed in regions characterized by a high content of grey matter and elevated density of nerve terminals. In this study we show for the first time a direct interaction between pp60 c-src and synaptophysin as a physiological target protein in neurons by demonstrating that endogenous pp60 c-src is able to phosphorylate synaptophysin (p38). p38 is a major constituent of the synaptic vesicle membrane protein and is thought to play a key role in the exocytosis of small synaptic vesicles and possibly small clear vesicles in neuroendocrine cells. KW - Synaptophysin KW - Synaptische Vesikel KW - Protein-Tyrosin-Kinasen Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86168 ER - TY - JOUR A1 - Schartl, Manfred A1 - Nanda, Indrajit A1 - Schlupp, Ingo A1 - Parzefall, Jakob A1 - Schmid, Michael A1 - Epplen, Jörg T. T1 - Genetic variation in the clonal vertebrate Poecilia formosa is limited to few truly hypervariable loci N2 - No abstract available. KW - Amazon Molly Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86359 ER - TY - JOUR A1 - Schartl, Angelika A1 - Schartl, Manfred T1 - Genes and cancer: Molecular biology of the melanoma oncogene of Xiphophorus N2 - No abstract available. KW - Schwertkärpfling KW - Krebs Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72670 ER - TY - CHAP A1 - Mahsberg, Dieter T1 - Brood care and family cohesion in the tropical scorpion Pandinus imperator (Koch) (Scorpiones: Scorpionidae) N2 - Pandinus imperator is a forest dweller of tropical West Africa. In the field, lobserved aggregations of up to 15 individuals. In the laboratory, mixed age groups of related and also unrelated animals lived jointly in terraria rarely showing within-group aggression or cannibalism. Brood-caring behavior of the mother influenced growth rate and survival probability of the young. With birth, mothers became very aggressive. To study family cohesion in Pandinus, experiments with family groups were conducted. Siblings aggregated around their mother. In choice experiments with two family groups, mothers were placed in enclosures that only the young were able to enter or to leave. Second instars significantly preferred the enclosure containing their own mother. Aggression among unrelated young of the same age was not observed. Feeding experiments studied the possible advantages of long-Iasting group living with regard to enhanced success in prey capture and its effect on growth of the young. Even groups of second instars were unable to subdue large prey on their own. Sibling groups with their mother removed suffered high mortality due to starvation and cannibalism compared to groups with mothers present. Here, young grew significantly faster: they shared the prey that only the mother was able to kill and dismember. Pandinus imperator has to be considered an intermediate subsocial scorpion. KW - Skorpion Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45776 ER - TY - JOUR A1 - Lehrnbecher, T. A1 - Merz, H. A1 - Sebald, Walter A1 - Poot, M. T1 - Interleukin 4 drives phytohemagglutinin-activated T cells through several cell cycles: no synergism between interleukin 2 and interleukin 4 N2 - Cell kinetic studies of T cells stimulated with the interleukin 2 (11-2), D-4, or both lymphokines were performed with conventional [3H] thymidine incorporation and with the bivariate BrdU/Hoechst technique. 11-2 and 11-4 are able to drive phytohemagglutininactivated T cells through more than one cell cycle. Neither synergistic nor inhibitory efl'ect on T -cell proliferationwas seen for the stimulation with both 11-2 and 11-4 as compared with the effect ofll-2 alone. The quantitative data ofthe cell cycle distribution ofphytohemagglutininactivated T cells suggestthat the population ofll-4-responsive cells is at least an overlapping population, if not a real subset of the ·population of the 11-2-responsive cells. KW - Biochemie KW - BrdU-Hoechst KW - cell cycle KW - flow cytometry KW - interleukin 2 KW - interleukin 4 Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62491 ER - TY - JOUR A1 - Merz, H. A1 - Fliedner, A. A1 - Orscheschek, K. A1 - Binder, T. A1 - Sebald, Walter A1 - Müller-Hermelink, H. K. A1 - Feller, A. C. T1 - Cytokine expression in T-cell lymphomas and Hodgkin's disease. Its possible implication in autocrine or paracrine production as a potential basis for neoplastic growth N2 - No abstract available KW - Biochemie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62483 ER - TY - JOUR A1 - Kruse, N. A1 - Lehrnbecher, T. A1 - Sebald, Walter T1 - Site-directed mutagenesis reveals the importance of disulfide bridges and aromatic residues for structure and proliferative activity of human interleukin-4 N2 - Mutant proteins (muteins) of human lnterleukin-4 (llA) were constructed by means of in vitro mutagenesis. The muteins were expressed in E. co/1, submitted to a renaturation and purification protocol and analysed for biological activity. Exchange of the cysteines at either position 46 or 99 which form one of the three disulfide bridges resulted. in a nearly co•mplete loss · of biological actiyity and an unstable protein. The exchange of tyrosine 124 also inactivated the protein, while a mutation of tyrosine 56 left some residual activity. Exchange of the other four cysteines or of · the single tryptophane had smaller etTects. KW - Biochemie KW - Interleukin 4 (human) KW - Recombinant KW - ln vitro mutagenesis KW - Structure-function Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62505 ER - TY - JOUR A1 - Preiser, J. C. A1 - Schmartz, D. A1 - Van der Linden, P. A1 - Content, J. A1 - Vanden Bussche, P. A1 - Buurman, W. A1 - Sebald, Werner A1 - Dupont, E. A1 - Pinsky, M. R. A1 - Vincent, J. L. T1 - Interleukin-6 administration has no acute hemodynamic or hematologic effect in the dog N2 - To investigate the possible hemodynamic efl'ects of interleukin-6 (IL-6), a single dose of 15 mcg/kg of recombinant IL-6 isolated from Escherichia coli was injected intravenously in six pentobarbital-anesthetized dogs. After 30 min, saline infusion was performed to maintain the - pulmonary artery balloon-occluded pressure at baseline Ievel. The animals were observed for up to 5 hours. No other hemodynamic alteration was observed than a gradual decline in cardiac output attributed to anesthesia. Hematologic variables, blood glucose, and total serum proteins were also constant. IL-6 levels were markedly elevated in the blood, bot no tumor necrosis factor activity was detected. Thus a primary role for IL-6 in the early cardiovascular alterations associated with septic shock seems unlikely. KW - Biochemie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62511 ER - TY - JOUR A1 - Tony, H. P. A1 - Lehrnbecher, T. A1 - Merz, H. A1 - Sebald, Werner A1 - Wilhelm, M. T1 - Regulation of IL-4 responsiveness in lymphoma B cells N2 - The responsiveness to IL-4 with and without costimulation with anti-IgM antibodies or phorbolester was studied in 35 cases of low grade non-Hodgkin Iymphoma by analyzing enhancement of CD23 and HLA dass li expression. The predominant phenotype responds directly to IL-4. Separate differentiation states can be distinguished according to coordinate or differential upregulation of CD23 and HLA dass II molecules by IL-4 alone, and differences in responsiveness to anti-IgM antibodies. A particular subgroup of B-lymphoma cells defines a separate stage of B-eeil differentiation. They fail to express high affinity binding sites for IL-4 and accordingly do not respond to IL-4- mediated signals. Cross-linking membrane lgM receptors or direct activation of protein kinase C via phorbolester induces IL-4 receptor expression and subsequent IL-4 reactivity. KW - Biochemie KW - B lymphocytes KW - CD23 KW - CLL KW - HLA class ll KW - IL-4 KW - IL-4-receptor KW - membrane immunoglobulin Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62520 ER - TY - JOUR A1 - Förnzler, Dorothee A1 - Wittbrodt, Joachim A1 - Schartl, M.anfred T1 - Analysis of an esterase linked to a locus involved in the regulation of the melanoma oncogene and isolation of polymorphic marker sequences in Xiphophorus N2 - Melanoma formation in Xiphophorus hybrids is mediated by a growth factor receptor tyrosine kinase oncogene encoded by the Tu locus. In the wild-type parental fish no tumors occur due to the activity of a locus that regulates the activity of the melanoma oncogene. Molecu/ar identification of this regulatory locus (R) requires a precise physical map of the chromosomal region. Therefore we studied esterase isozymes in Xiphophorus, two of which have been previously reported to be linked to locus R. We confinn that ES 1 is a distant marker for R ( approx. 30cM), and contrary to earlier studies, we show that this isozyme is present in all species of the genus and at similar activity Ievels in all organs tested. ES4, which has also been reported to be linked to R, was found to be a misclassification of liver ES1. In an attempt to identify markersthat bridge the large distance between ESl and R, we have generated DNA probes which are highly polymorphic. They will be useful in finding Iandmarks on a physical map of the R-containing chromosomal region. KW - Physiologische Chemie KW - Xiphophorus KW - melanoma ; oncogene regulation ; esterase ; molecular marker sequences Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61726 ER - TY - JOUR A1 - Schartl, Manfred A1 - Schlupp, Ingo A1 - Schartl, Angelika A1 - Meyer, Manfred K. A1 - Nanda, Indrajit A1 - Schmid, Michael A1 - Epplen, Jörg T. A1 - Parzefall, Jakob T1 - On the stability of dispensable constituents of the eukaryotic genome: Stability of coding sequences versus truly hypervariable sequences in a clonal vertebrate, the amazon molly, Poecilia formosa N2 - In dooal unisexual vertebrales, the genes specifying the males become dispensable. To study tbe rate of such geoes the gynogeoetic all-female fisb Poecilillfonnolll was treated with androgens. Phenotypic males were obtained that exbibited the complete set of male cbaracteristics of dosely related gooocboristic species, induding body proportions, pigmentation, the extremely complex insemination apparatus of poecilüd fish, sexual bebavior, and spermatogeoesls. Tbe apparent stabllity of such genic structures, induding those involved in androgen regulation, is contrasted by high instability of noncoding sequeaces. Frequent mutations, thelr donal transmission, and at least two truly hypervariable Iod leading to individual difl'ereaces between these othenrise donal organisms were detected by DNA fingerprinting. These observations substantiate the concept that also in "ameiotic" vertebrates certain compartments of the genome are more prooe to mutatiooal alterations than others. KW - Physiologische Chemie KW - DNA fingerprinting KW - androgen-induced masculinization KW - gynogeaesls KW - simple repeat sequences Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61731 ER - TY - JOUR A1 - Winkler, Christoph A1 - Vielkind, Jürgen R. A1 - Schartl, Manfred T1 - Transient expression of foreign DNA during embryonic and larval development of the medaka fish (Oryzias latipes) N2 - Species of small fish are becoming useful tools for studies on vertebrate development. Wehave investigated the developing embryo of the Japanese medaka for its application as a transient expression system for the in vivo analysis of gene regulation and function. The temporaland spatial expression patterns ofbacterial chloramphenicol acetyltransferase and galactosidase reporter genes injected in supercoiled plasmid form into the cytoplasm of one cell of the two-cell stage embryo was promoter-specific. The transient expression was found to be mosaic within the tissue and organs reflecting the unequal distribution of extrachromosomal foreign DNA and the intensive cell mixing movements that occur in fish embryogenesis. The expression data are consistent with data on DNA fate. Foreign DNA persisted during embryogenesis and was still detectable in some 3- and 9-month-old adult fish; it was found in high molecular weight form as weil as in circular plasmid conformations. The DNA was replicated during early and late embryogenesis. Our data indicate that the developing medaka embryo is a powerful in vivo assay system for studies of gene regulation and function. KW - Physiologische Chemie KW - Medaka - Genetransfer - Transient expression - DNA fate - Fish developmental biology Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61743 ER - TY - JOUR A1 - Haas, Albert A1 - Brehm, Klaus A1 - Kreft, Jürgen A1 - Goebel, Werner T1 - Cloning, characterization, and expression in Escherichia coli of a gene encoding Listeria seeligeri catalase, a bacterial enzyme highly homologous to mammalian catalases N2 - A gene coding for catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase; EC 1.11.1.6) of the grain-positive bacterium Listeria seeligeri was cloned from a plasmid library of EcoRI-digested chromosomal DNA, with Escherichia coli DHSa as a host. The recombinant catalase was expressed in E. coli to an enzymatic activity approximately SO times that of the combined E. coli catalases. The nucleutide sequence was determined, and the deduced amino acid sequence revealed 43.2% amino acid sequence identity between bovine liver catalase and L. seeligeri catalase. Most of the amino acid residues which are involved in catalytic activity, the formation of the active center accession channel, and heme binding in bovine liver catalase were also present in L. seeligeri catalase at the corresponding positions. The recombinant protein contained 488 amino acid residues and had a calculated molecular weight of 55,869. The predicted isoelectric point was 5.0. Enzymatic and genetic analyses showed that there is most probably a single catalase of this type in L. seeligeri. A perfect 21-bp inverted repeat, which was highly homologous to previously reported binding sequences of the Fur (ferric uptake regulon) protein of E. coli, was detected next to the putative promoter region of tbe L. seeligeri catalase gene. KW - Biologie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60536 ER - TY - JOUR A1 - Schülein, Ralf A1 - Kreft, Jürgen A1 - Gonski, Sigrid A1 - Goebel, Werner T1 - Preprosubtilisin Carlsberg processing and secretion is blocked after deletion of amino acids 97-101 in the mature part of the enzyme N2 - During an investigation into the substrate specificity and processing of subtilisin Carlsberg from Bacillus licheniformis, two major independent findings were made: (i) as has been shown previously, a stretch of five amino acids (residues 97-101 of the mature enzyme) that loops out into the binding cleft is involved in substrate binding by subtilisin Carlsberg. In order to see whether this loop element also determines substrate specificity, the coding region for these five amino acids was deleted from the cloned gene for subtilisin Carlsberg by site-directed mutagenesis. Unexpectedly the resulting mutant preproenzyme (P42c, Mr=42 kDa) was not processed to the mature form (Mr = 30 kDa) and was not released into the medium by a proteasedeficient B. subtilis host strain; rather, it accumulated in the cell membrane. This result demonstrates that the integrity of this loop element, which is very distant from the processing cleavage sites in the preproenzyme, is required for secretion of subtilisin Carlsberg. (ii) In culture supernatants from B. subtilis harbouring the cloned wild-type subtilisin Carlsberg gene the transient appearance (at 0-3 h after onset of stationary phase) of a processing intermediate (P38c, Mr = 38 kDa) oftbis protease could be demonstrated. P38c very probably represents a genuine proform of subtilisin Carlsberg. KW - Biologie KW - Bacillus KW - Proenzyme KW - Subtilisin maturation KW - Site-directed mutagenesis KW - Subtilisin Carlsberg Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60577 ER - TY - JOUR A1 - Vortkamp, A. A1 - Thias, U. A1 - Gessler, Manfred A1 - Rosenkranz, W. A1 - Kroisel, P. M. A1 - Tommerup, N. A1 - Kruger, G. A1 - Gotz, J. A1 - Pelz, L. A1 - Grzeschik, Karl-Heinz T1 - A somatic cell hybrid panel and DNA probes for physical mapping of human chromosome 7p N2 - No abstract available KW - Biochemie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59217 ER - TY - JOUR A1 - Dabauvalle, Marie-Christine A1 - Loos, Karin A1 - Merkert, Hilde A1 - Scheer, Ulrich T1 - Spontaneous assembly of pore complex-containing membranes ("Annulate lamellae") in Xenopus egg extract in the absence of chromatin N2 - No abstract available Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32797 ER - TY - JOUR A1 - Fischer, Dagmar A1 - Weißenberger, Dieter A1 - Scheer, Ulrich T1 - Assigning functions to nucleolar structures N2 - Nucleoli provide the fascinating possibility of linking morphologically distinct structures such as those seen in the electron microscope with biochemical f eatures of the formation and step wise maturation of ribosomes. Localization of proteins by immunocytochemistry and of rRNA genes and their transcripts by in situ hybridization has greatly improved our understanding of the structural-functional relationships of the nucleolus. The present review describes some recent results obtained by electron microscopic in situ hybridization and argues that this approach has the potential to correlate each step of the complex pre-rRNA maturation pathway with nucleolar structures. Evidence is accumulating that the nucleolus-specific U3 snRNPs (small nuclear ribonucleoprotein particles) participate in rRNA processing events, similar to the role played by the nucleoplasmic snRNPs in mRNA maturation. The intranucleolar distribution of U3 snRNA is consistent with the view that it is involved in both early and late stages of pre-rRNA processing. Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34258 ER - TY - JOUR A1 - Dandekar, Thomas T1 - Yeast U3 localization and correct sequence (snR17a) and promotor activity (snR17b) identified by homology search N2 - No abstract available KW - yeast U3 localization Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29781 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Tollervey, D. T1 - Thirty-three nucleotides of 5' flanking sequence including the TATA box are necessary and sufficient for efficient U2 snRNA transcription in Schizosaccharomycespombe N2 - No abstract available Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29959 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Stripecke, Renata A1 - Gray, Nicola K. A1 - Goossen, Britta A1 - Constable, Anne A1 - Johansson, Hans E. A1 - Hentze, Matthias W. T1 - Identification of a novel iron-responsive element in murine and human erythroid \(\delta\)-aminolevulinic acid synthase mRNA N2 - No abstract available Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29929 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Argos, Patrick T1 - Chaperonin-mediated protein folding at the surface of groEL through a "molten globule" intermediate N2 - No abstract available Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29939 ER - TY - JOUR A1 - Maschwitz, Ulrich A1 - Fiala, Brigitte A1 - Moog, J. A1 - Saw, L. G. T1 - Two new myrmecophytic associations from the Malay Peninsula: ants of the genus Cladomyrma as partners of Saraca thaipingensis and Crypteronia griffithii N2 - In Peninsular Malaysia the trees Saraca thaipingensis (Caesalpiniaceae) and Crypteronia griffithii (Crypteroniaceae) are inhabited by ants. In the vicinity ofGombak, near Kuala Lumpur, the hollow internodes of young Saraca thaipingensis plants are colonized mainly by two Cladomyrma species. In larger trees a Crematogaster sp. is also found. Crypteronia griffithii is inhabited by a third species of Cladomyrma. None of these species is conspecific with any of the three Cladomyrma taxa so far described. The colonies are founded by single mated queens, which have a conspicuous, sphecid wasp-like behaviour when searching for host plants and nest sites. They chew holes into the plant intern odes and hollow them out to provide nest sites. Coccids and pseudococcids are cultivated within the internodes. The homopterans are not carried by queens on their nuptial flights. They apparently find their way by themselves into the cavities or are perhaps carried there by the worker ants. The Cladomyrma ants on Crypteronia are not aggressive, in contrast to those on Saraca thaipingensis. The relationship of Crypteronia with ants seems to be obligatory, whereas Saraca was only partly colonized by Cladomyrma. The interaction of Saraca with Crematogaster sp. is loose and facultative, since the Crematogaster sp. also lives on other tree species. Our studies have now revealed four Cladomyrma spp. which are regularly associated with plants. The genus therefore seems to have an entirely myrmecophytic way of life. KW - Myrmecophytism ; Malaysia ; trophobionts ; colony foundation ; Cladomyrma Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32992 ER - TY - JOUR A1 - Schlupp, I. A1 - Parzefall, J. A1 - Schartl, Manfred T1 - Male mate choice in mixed bisexual/-unisexual breeding complexes of Poecilia (Teleostei: Poeciliidae) N2 - The livebearing all-female fish Poecilia formosa reproduces by gynogenesis, a modified form of parthenogenesis. P. formosa forms at least two breeding complexes: in its northern range it exists sympatrically with Poecilia latipinna and in its southern range with Poecilia mexicana. Differences between these complexes and their possible origin are discussed. Embryogenesis is triggered by sperm of males of these closely related sympatric species. Because inheritance is stricdy maternal, from the male point of view energy and time invested are totally lost. In this study we wanted to elucidate whether males are able to distinguish between conspecific and parasitic females. It could be shown that males are able to distinguish females optically, but that this ability was obscured as soon as chemical and/or tactile contact was possible. Furthermore, we found that females in an attractive phase of their sexual cycle are always preferred, regardless of species. This is possibly the mechanism by which parasitic females obtain the matings they need to reproduce. KW - Poecilia (Teleostei: Poeciliidae) Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80309 ER - TY - JOUR A1 - Malitschek, B. A1 - Schartl, Manfred T1 - Rapid identification of recombinant baculoviruses using PCR N2 - no abstract available KW - PCR Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80328 ER - TY - JOUR A1 - Fiala, Brigitte A1 - Maschwitz, Ulrich T1 - Extrafloral nectaries in the genus Macaranga (Euphorbiaceae) in Malaysia: comparative studies of their possible significance as predispositions for myrmecophytism. N2 - So me species of the paleotropical tree genus Macaranga (Euphorbiaceae) live in elose association with ants. Thc genus comprises the full range of species from those not regularly inhabited by ants to obligate myrmecophytes. In Malaysia (peninsular and Borneo) 23 ofthe 52 species areknown to be ant-associated (44%). The simplest structural adaptation of plants to attract ants are extrafloral nectaries. We studied the distribution of extraflural nectaries in the genus Macaranga to assess the significance of this character as a possible predisposition for the evolution of obligate myrmecophytism. All species have marginal glands on the leaves. However, only the glands of nonmyrmecophytic species function as nectaries, whereas liquids secreted by these glands in myrmecophytic species did not contain sugar. Some non-myrmecophytic Macaranga and transitional Macaranga species in addition have extrafloral nectaries on the leaf blade near the petiole insertion. All obligatorily myrmecophytic Macaranga species, however, lack additional glands on the lamina. The non-myrmecophytic species are visited by a variety of different ant species, whereas myrmecophytic Macaranga are associated only with one specific ant-partner. Since these ants keep scale insects in the hollow sterns, reduction of nectary production in ant-inhabited Macaranga seems to be biologically significant. We interpret this as a means of (a) saving the assimilates and (b) stabilization of maintenance of the association's specificity. Competition with other ant species for food rewards is avoided and thereby danger ofweakening the protective function ofthe obligate antpartner for the plant is reduced. A comparison with other euphorb species living in the same habitats as Macaranga showed that in genera in which extrafloral nectaries are widespread, no myrmecophytes have evolved. Possession of extrafloral nectaries does not appear to be essential for the development of symbiotic ant-plant interactions. Other predispositions such as nesting space might have played a more important role. KW - Macaranga KW - extrafloral nectaries KW - ant-plant interactions KW - evolution of myrmecophytism KW - Malaysia Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-42863 ER - TY - JOUR A1 - Dabauvalle, Marie-Christine A1 - Scheer, Ulrich T1 - Assembly of nuclear pore complexes in Xenopus egg extract N2 - No abstract available Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41194 ER - TY - JOUR A1 - Dandekar, Thomas T1 - Olbers' Paradox (peer-reviewed scientific correspondence) N2 - No abstract available Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31672 ER - TY - JOUR A1 - Schartl, Manfred A1 - Erbelding-Denk, Claudia A1 - Nanda, Indrajit A1 - Schmid, Michael A1 - Schröder, Johannes Horst A1 - Epplen, Jörg T. T1 - Mating success of subordinate males in a poeciliid fish species, Limia perugiae N2 - No abstract available. KW - Lebendgebärende Zahnkarpfen KW - Perugia-Kärpfling Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86349 ER - TY - JOUR A1 - Adam, Dieter A1 - Maueler, Winfried A1 - Schartl, Manfred T1 - Transcriptional activation of the melanoma inducing Xmrk oncogene in Xiphophorus N2 - The melanoma inducing locus of Xiphophorus encodes a tumorigenic version of a novel putative receptor tyrosine kinase (Xmrk). To elucidate the mechanism of oncogenic activation of Xmrk, we compared the structure and expression of two oncogenic loci with the corresponding proto-oncogene. Only minor structural alterations were found to be specific for the oncogenic Xmrk genes. Marked overexpression of the oncogene transcripts in melanoma, which are approximately 1 kb shorter than the proto-oncogene transcript, correlates with the malignancy of the tumors. The tumor transcripts are derived from an alternative transcription start site that is used only in the oncogenic loci. Thus, oncogenic activation of the melanoma inducing Xmrk gene appears primarily to be due to novel transcriptional control and overexpression. KW - Schwertkärpfling KW - Onkogen KW - Melanom Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87584 ER - TY - JOUR A1 - Hannig, Gerhard A1 - Ottilie, Sabine A1 - Schartl, Manfred T1 - Conservation of structure and expression of the c-yes and fyn genes in lower vertebrates N2 - The src-gene family in mammals and birds consists of 9 closely related protein tyrosine kinases. We have cloned the c-yes and fyn bomologues of the src-family from the teleost fish Xiphophorus helleri. Both genes show a high degree of sequence conservation and exhibit all structural motifs diagnostic for functional src-like protein tyrosine kinases. Sequence comparisons revealed three domains (exon 2, exons 3--6, exons 7-12) which evolve at different rates. Both genes exhibit an identical expression pattern, with preferential expression in neural tissues. No transcripts of c-yes were found in liver wbich is contrary to the situation in higher vertebrales. In malignant melanoma, elevated Ieveis of c-yes andfyn were detected indicating a possible function during secondary steps of tumor progression for src-related tyrosine kinases. KW - Konservierung KW - Gen KW - Niedere Wirbeltiere Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86723 ER - TY - CHAP A1 - Epplen, J. T. A1 - Ammer, H. A1 - Epplen, C. A1 - Kammerbauer, C. A1 - Mitreiter, R. A1 - Roewer, L. A1 - Schwaiger, W. A1 - Steimle, V. A1 - Zischler, H. A1 - Albert, E. A1 - Andreas, A. A1 - Beyermann, B. A1 - Meyer, W. A1 - Buitkamp, J. A1 - Nanda, I. A1 - Nürnberg, P. A1 - Pena, S. D. J. A1 - Pöche, H. A1 - Sprecher, W. A1 - Schartl, Manfred A1 - Weising, K. A1 - Yassouridis, A. T1 - Oligonucleotide fingerprinting using simple repeat motifs: a convenient, ubiquitously applicable method to detect hypervariability for multiple purposes N2 - A panel of simple repetitive oligonucleotide probes has been designed and tested for multilocus DNA fingerprinting in some 200 fungal, plant and animal species as well as man. To date at least one of the probes has been found to be informative in each species. The human genome, however, has been the major target of many fingerprintins studies. Using the probe (CAC)5 or (GTG)5, individualization of all humans is possible except for monozygotic twins. Paternity analyses are now perfonned on a routine basis by the use of multilocus fingerprints, inctuding also cases of deficiency, i.e. where one of the parents is not available for analysis. In forensie science stain analysis is feasible in all tissue remains containing nuc)eated cells. Depending on the degree of DNA degradation a variety of oligonucleotides are informative, and they have been proven useful in actual case work. Advantages in comparison to other methods including enzymatic DNA amplification techniques (PCR) are evident. Fingerprint patterns of tumors may be changed due to the gain or loss of chromosomes and/or intrachromosomal deletion and amplification events. Locus-specific probes were isolated from the human (CAC)5/( GTG)5 fingerprint with a varying degree of informativeness (monomorphic versus truly hypervariable markers). The feasibility of three different approaches. for the isolation of hypervariable mono-locus probes was evaluated. Finally, one particular mixed simple (gt)n(ga)m repeat locus in the second intron of the HLA-DRB genes has been scrutinized to allow comparison of the extent of exon-encoded (protein-) polymorphisms versus intronie bypervariability of simple repeats: adjacent to a single gene sequence (e.g. HLA-DRB1*0401) many different length alleles were found. Group-specific structures of basic repeats were identified within the evolutionarily related DRB alleles. As a further application it is suggested here that due to the ubiquitous interspersion of their targets, short probes for simple repeat sequences are especially useful tools for ordering genomic cosmid, yeast artificial chromosome and phage banks. KW - DNS KW - Fingerprint-Verfahren Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86371 ER - TY - CHAP A1 - Adam, D. A1 - Schartl, A. A1 - Andexinger, S. A1 - Hölter, S. A1 - Wilde, B. A1 - Schartl, Manfred T1 - Genetic factors in tumour formation: The melanoma-inducing gene of Xiphophorus N2 - No abstract available. KW - Humangenetik KW - Tumor KW - Entstehung Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86388 ER - TY - JOUR A1 - Thiry, Marc A1 - Scheer, Ulrich A1 - Goessens, Guy T1 - Localization of nucleolar chromatin by immunocytochemistry and in situ hybridization at the electron microscopic level N2 - Nucleoli are the morphological expression of the activity of a defined set of chromosomal segments bearing rRNA genes. The topological distribution and composition of the intranucleolar chromatin as well as the definition of nucleolar structures in which enzymes of the rDNA transcription machinery reside have been investigated in mammalian cells by various immunogold labelling approaches at the ultrastructural level. The precise intranucleolar location of rRNA genes has been further specified by electron microscopic in situ hybridization with a non-autoradiographic procedure. Our results indicate that the fibrillar centers are the sole nucleolar structures where rDNA, core histones, RNA polymerase I and DNA to po isomerase I are located together. Taking into account the potential value and limitations of immunoelectron microscopic techniques, we propose that transcription of the rRNA genes takes place within the confines of the fibrillar centers, probably close to the boundary regions to the surrounding dense fibrillar component. Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39289 ER - TY - JOUR A1 - Schartl, Manfred A1 - Adam, Dieter T1 - Molecular cloning, structural characterization, and analysis of transcription of the melanoma oncogene of xiphophorus N2 - No abstract available KW - Physiologische Chemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61989 ER - TY - JOUR A1 - Schlupp, Ingo A1 - Parzefall, Jakob A1 - Epplen, Jörg T. A1 - Nanda, Indrajit A1 - Schmid, Michael A1 - Schartl, Manfred T1 - Pseudomale behaviour and spontaneous masculinization in the all-female teleost Poecilia formosa (Teleostei: Poeciliidae) N2 - Pseudosexual behaviour is a rare phenomenon associated with unisexuality in vertebrates. In the gynogenetic, all-female teleost Poecilia formosa, rare individuals occur that resemble males of closely related gonochoristic species both in behaviour and external morphology. These masculinized gynogens and normal gynogens are members of the same clone, as demonstrated by DNA-fingerprinting. The behaviour of these masculinized gynogens is described and compared to the behaviour of the gonochoristic species Poecilia mexicana, P. latipinna and their hybrid as weil as androgen-treated individuals of P. formosa. No statistically significant difTerences were found between masculinized gynogens and hormonetreated individuals nor between the gonochoristic P. mexicana and P. latipinna males. Differences exist between gonochoristic and unisexual species. Passihle causes and effects of masculinized gynogens are discussed. KW - Physiologische Chemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61688 ER - TY - JOUR A1 - Kruse, N. A1 - Tony, H. P. A1 - Sebald, Walter T1 - Conversion of human interleukin-4 into a high affinity antagonist by a single amino acid replacement N2 - lnterleukin-4 (IL-4) represents a prototypic lymphokine (for a recent review see Paul, 1991). It promotes differentiation of B-cells and the proliferation of T- and B-cell, and other cell types of the lymphoid system. An antagonist of human IL-4 was discovered during the studies presented here after Tyr124 of the recombinant proteinbad been substituted by an aspartic acid residue. This IL-4 variant, Y124D, bound with high affinity to the IL-4 receptor (K\(_D\) = 310 pM), but retained no detectable proliferative activity for T -<:ells and inhibited IL-4-dependent T -cell proliferation competitively (K\(_i\) = 620 pM). The loss of efficacy in variant Y124D was estimated to be > 100-fold on the basis of a weak partial agonist activity for the very sensitive induction of CD23 positive B-cells. The subsitution of Tyr124 by either phenylalanine, histidine, asparagine, Iysine or glycine resulted in partial agonist variants with unaltered receptor binding atTmity and relatively small deficiencies in efficacy. These results demoostrate that high affinity binding and signal generation can be uncoupled efticiently in a Iigand of a receptor betonging to the recently identified hematopoietin receptor family. In addition we show for the first time, that a powerful antagonist acting on the IL-4 receptor system can be derived from the IL-4 protein. KW - Biochemie KW - drug design KW - partial agonists KW - receptor signalling Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62469 ER - TY - JOUR A1 - Dummer, R. A1 - Posseckert, G. A1 - Nestle, F. A1 - Witzgall, R. A1 - Burger, M. A1 - Becker, J. C. A1 - Schäfer, E. A1 - Wiede, J. A1 - Sebald, Walter A1 - Burg, G. T1 - Soluble interleukin-2 receptors inhibit interleukin 2-dependent proliferation and cytotoxicity: explanation for diminished natural killer cell activity in cutaneous T-cell lymphomas in vivo? N2 - No abstract available KW - Biochemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62473 ER - TY - JOUR A1 - Hong, Yunhan A1 - Schartl, Manfred T1 - Structure of the rainbow trout metallothionein A gene N2 - To investigate the regulation of metallothionein-encoding genes in fish, we have isolated and sequenced the rainbow trout metallothionein-A-encoding gene (tMT-A) by polymerase chain reaction. This gene spans about 1.1 kb, consists of three exons and two introns, and has an A+ T-rieb 5' -region which contains a TATAAA signal, and two metal responsive elements (MREs). The transcription start point is centered around an A residue 81 nt upstream of the ATG codon. KW - Physiologische Chemie KW - Recombinant DNA ; polymerase chain reaction ; metallothionein gene ; rainbow trout ; fish Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61679 ER - TY - JOUR A1 - Wittbrodt, Joachim A1 - Lammers, Reiner A1 - Malitschek, Barbara A1 - Ullrich, Axel A1 - Schartl, Manfred T1 - Xmrk receptor tyrosine kinase is activated in Xiphophorus malignant melanoma N2 - Xmrk encodes a putative transmembrane glycoprotein of the tyrosine kinase family and is a melanoma-inducing gene in Xiphophorus. We attempted to investigate the biological function of the putative Xmrk receptor by characterizing its signalling properties. Since a potential Iigand for Xmrk has not yet been identified, it has been difficult to analyse the biochemical properlies and biological function of this cell surface protein. In an approach towards such analyses, the Xmrk extracellular domain was replaced by the closely related Iigand-binding domain sequences of the human epidennal growth factor receptor (HER) and the ligand-induced activity of the chimeric HER-Xmrk proteinwas examined. We show that the Xmrk protein is a functional receptor tyrosine kinase, is highly active in malignant melanoma and displays a constitutive autophosphorylation activity possibly due to an activating mutation in its extracellular or transmembrane domain. In the focus formation assay the HER-Xmrk chimera is a potent transfonning protein equivalent to other tyrosine kinase oncoproteins. KW - Physiologische Chemie KW - chimeric RTKs KW - melanoma KW - RTK KW - Xiphophorus Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61699 ER - TY - JOUR A1 - Götz, Rudolf A1 - Raulf, Friedrich A1 - Schartl, Manfrad T1 - Brain-derived neurotrophic factor is more highly conserved in structure and function than nerve growth factor during vertebrate evolution N2 - Mammalian nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are members of a protein family with perfectly conserved domains arranged around the cysteine residues thought to stabilize an invariant three-dimensional scaffold in addition to distinct sequence motifs that convey different neuronal functions. To study their structural and functional conservation during evolution, we have compared NGF and BDNF from a lower vertebrate, the teleost fi.sh Xiphophorus, with the mammalian homlogues. Genomic clones encoding fish NGF and BDNF were isolated by cross-hybridization using probes from the cloned mammalian factors. Fish NGF and BDNF were expressed by means of recombinant vaccinia viruses, purified, and their neuronal survival specificities for different classes of neurons were found to mirror those of the mammalian factors. The half-maximal survival concentration for chick sensory neurons was 60 pg/ml for both fish and mammalian purifi.ed recombinant BDNF. However, the activity ofrecombinant fish NGF on both chick sensory and sympathetic neurons was 6 ng,lml, 75-fold lower than that of mouse NGF. The different functional conservation of NGF and BDNF is also reflected in their structures. The DNA-deduced amino acid sequences of processed mature fish NGF and BDNF showed, compared to mouse, 63% and 90% identity, respectively, indicating that NGF bad reached an optimized structure later than BDNF. The retrograde extrapolation of these data indicates that NGF and BDNF evolved at strikingly different rates ftom a common ancestral gene about 600 million years ago. By RNA gel blot anaJysis NGF mRNA was detected during late embryonie development; BDNF was present in adult brain. KW - Physiologische Chemie KW - Brain-derived neurotrophic factor KW - Nerve growth factor KW - Fish KW - Recombinant protein expression KW - Neuronal survival Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61703 ER - TY - JOUR A1 - Nanda, Indrajit A1 - Schartl, Manfred A1 - Feichtinger, Wolfgang A1 - Epplen, Jörg T. A1 - Schmid, Michael T1 - Early stages of sex chromosome differentiation in fish as analysed by simple repetitive DNA sequences N2 - Animal sex chromosome evolution has started on different occasions with a homologous pair of autosomes leading to morphologically differentiated gonosomes. In contrast to other vertebrate classes, among fishes cytologically dernonstrahle sex chromosomes are rare. In reptiles, certain motifs of simple tandemly repeated DNA sequences like (gata)\(_n\)/(gaca)\(_m\) are associated with the constitutive heterochromatin of sex chromosomes. In this study a panel of simple repetitive sequence probes was hybridized to restriction enzyme digested genomic DNA of poeciliid fishes. Apparent male heterogamety previously established by genetic experiments in Poecilia reticulata (guppy) was correlated with male-specific hybridization using the (GACA)\(_4\) probe. The (GATA)\(_4\) oligonucleotide identifies certain male guppies by a Y chromosomal polymorphism in the outbred population. In cantrast none of the genetically defined heterogametic situations in Xiphophorus could be verified consistently using the collection of simple repetitive sequence probes. Only individuals from particular populations produced sex-specific patterns of hybridization with (GATA)\(_4\). Additional poeciliid species (P. sphenops, P. velifera) harbour different sex-specifically organized simple repeat motifs. The observed sex-specific hybridization patterns were substantiated by banding analyses of the karyotypes and by in situ hybridization using the (GACA)\(_4\) probe. KW - Physiologische Chemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61715 ER - TY - JOUR A1 - Brehm, Klaus A1 - Haas, Albert A1 - Goebel, Werner A1 - Kreft, Jürgen T1 - A gene encoding a superoxide dismutase of the facultative intracellular bacterium Listeria monocytogenes N2 - A gene (Imsod) encoding superoxide dismutase (SOD; EC 1.15.1.1) of the facultative intracellular pathogen, Listeria monocytogenes, was cloned by functional complementation of an SOD-deficient Escherichia coli mutant. The nucleotide sequence was determined and the deduced amino acid (aa) sequence (202 aa) showed close similarity to manganese-containing SOD's from other organisms. Subunits of the recombinant L. monocytogenes SOD (re-SOD) and of both E. coli SODs formed enzymatically active hybrid enzymes in vivo. DNA/DNA-hybridization experiments showed that this type of recombinant re-sod gene is conserved within the genus Listeria. KW - Biologie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60515 ER - TY - JOUR A1 - Haas, Albert A1 - Dumbsky, Martina A1 - Kreft, Jürgen T1 - Listeriolysin genes: complete sequence of ilo from Listeria ivanovii and of lso from Listeria seeligeri N2 - The completc DNA scqucnccs coding for thc thiol-activated cytolysins from Listeria ivanovii, ivanolysin 0 (ILO) and for sccligerolysin 0 (LSO) from Listeria seeligeri have been dctermined. Thc deduced amino acid scquences revealed that: (i) the primary translation products comprise 528 (ILO) and 530 (LSO) amino acids. respectively. (ii) ILO contains two cysteines. LSO has a substitution in the conserved cysteine motif. KW - Biologie KW - Thiol-activated cytolysin KW - Listeriolysin O KW - Cysteine: motif KW - ( L. ivanovii ) KW - ( L. selligeri) Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60529 ER - TY - JOUR A1 - Gessler, Manfred A1 - Grupe, Andrew A1 - Grzeschik, Karl-Heinz A1 - Pongs, Olaf T1 - The potassium channel gene HK1 maps to human chromosome 11p14.1, close to the FSHB gene N2 - Transiently activating (A-type) potassium (K) channels are important regulators of action potential and action potential firing frequencies. HK1 designates the firsthuman cDNA that is highly homologous to the rat RCK4 cDNA that codes for an A-type K-channel. The HK1 channel is expressed in heart. By somatic cell hybrid analysis, the HK1 gene has been assigned to human chromosome 11p13-pl4, the WAGR deletion region (Wilms tumor, aniridia, genito-urinary abnormalities and mental retardation). Subsequent pulsed field gel (PFG) analysis and comparison with the well-established PFG map of this region localized the gene to 11p14, 200-600 kb telomeric to the FSHB gene. KW - Biochemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59184 ER - TY - JOUR A1 - Gessler, Manfred A1 - König, A. A1 - Bruns, G. A. P. T1 - The genomic organization and expression of the WT1 gene N2 - The Wilms tumor gene WTl, a proposed tumor suppressor gene, has been identifled based on its location within a homozygous deletion found in tumor tissue. The gene encodes a putative transcription factor containing a Cys/His zinc finger domain. The critical homozygous deletions, however, are rarely seen, suggesting that in many cases the gene may be inactivated by more subtle alterations. To facilitate the seareh for smaller deletions and point mutations we have established the genomic organization of the WTl gene and have determined the sequence of all 10 exons and flanking intron DNA. The pattern of alternative splicing in two regions has been characterized in detail. These results will form the basis for future studies of mutant alleles at this locus. KW - Biochemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59195 ER - TY - JOUR A1 - Wolf, Markus A1 - Klug, Jörg A1 - Hackenberg, Reinhard A1 - Gessler, Manfred A1 - Grzeschik, Karl-Heinz A1 - Beato, Miguel A1 - Suske, Guntram T1 - Human CC10, the homologue of rabbit uteroglobin: genomic cloning, chromosomal localization and expression in endometrial cell lines N2 - No abstract available KW - Biochemie Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59206 ER - TY - JOUR A1 - Fiala, Brigitte A1 - Maschwitz, Ulrich T1 - Food bodies and their significance for obligate ant-association in the tree genus Macaranga (Euphorbiaceae) N2 - The production of extrafloral nectar and food bodies plays an important role in many tropical ant-plant mutualisms. In Malaysia, a close association exists between ants and some species of the pioneer tree genus Macaranga (Euphorbiaccac). Macaranga is a very diverse genus which exhibits all stages ofintcraction with ants, from facultative to obligatory associations. The ants nest inside the hollow inlcrnodes and reed mainly on food budies provided by the plants. Food body production had previously been reported only in myrrnecophytic Macaranga species, where it is usually coneentrated on protected parts or the plants such as recurved stipules. We found that non-myrmecophytic Macaranga species also produce food bodies on leaves and stems, where they are collected by a variety or ants. Levels of food body production differ between facultatively and obligatorily ant-associated species but also among the various non-myrmecophytes. This may he rdated to the degree of interaction with ants. Food body production starts at a younger age in the myrmccophytic species than in the transitional or non-myrmcccophytic Macaranga. Although food bodies of the non-inhabited Macaranga species are collected by a variety of ants, there is nu evidence of association with specific ant species. Our observations suggest that food bodies enhance the evolution of ant-plant interactions. Production of food bodies alone, however, does not appear to be the most important factor for the development of obligate myrmccopllytism in Macaranga. KW - Ant-plant interactions KW - evolution KW - food bodies KW - Macaranga KW - Malaysia KW - myrmrcophytism Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32921 ER - TY - JOUR A1 - Grafe, T. Ulmar A1 - Schmuck, Richard A1 - Linsenmair, Karl Eduard T1 - Reproductive energetics of the African Reed Frogs, Hyperolius viridiflavus and Hyperolius marmoratus N2 - No abstract available Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31187 ER - TY - JOUR A1 - Kobelt, F. A1 - Linsenmair, Karl Eduard T1 - Adaptations of the reed frog Hyperolius viridiflavus (Hyperoliidae) to its arid environment. VI. The iridophores in the skin as radiation reflectors N2 - No abstract available Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30563 ER - TY - JOUR A1 - Vortkamp, Andrea A1 - Franz, Thomas A1 - Gessler, Manfred A1 - Grzeschik, Karl-Heinz T1 - Deletion of GLI3 supports the homology of the human Greig cephalopolysyndactyly syndrome (GCPS) and the mouse mutant extra toes (Xt) N2 - No abstract available Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30166 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Argos, Patrick T1 - A novel heterodimeric cysteine protease is required for interleukin 1ß processing in monocytes N2 - No abstract available Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29986 ER -