TY  - JOUR
A1  - Kreft, Jürgen
T1  - Reovirus-specific messenger ribonucleoprotein particles from Hela cells
N2  - When reovirus-infected Hela cells are incubated at 43°C virus-specific messenger RNA is released ~rom the polysomes. It accumulates free in the cytoplasm as messenger ribonucleoprotem partIcles (mRNPs). The:e part~cles have a sedimentati~n rate of about 50S and a buoyant densIty m CsCI of 1.42 g/cm . ReovIrus mRNPs contam, beSIdes all three size classes of reovirus messenger RNA, the same spectrum of proteins found in the polysomal mRNPs from uninfected cells, plus t~o addi~ional pr?teins with molecular masses of 7000~ d and 110000 d, respectively. Electron mIcroscoPIc exammatlOn of the reovIrus mRNP fractIOn reveals specific Y-shaped structures wIth a total mean length ofO.5Ilm.
KW  - Hela Cells
KW  - Reovirus
KW  - Messenger Ribonucleoprotein Particles
KW  - mRNP-Proteins
KW  - Electron Microscopy
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47028
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Sommerville, John
A1  - Müller, Ulrike
T1  - DNA is assembled into globular supranucleosomal chromatin structures by nuclear contents of amphibian oocytes
N2  - The assembly of DNA into nucleosomal and supranucleosomal chromatin structures has been studied (i) by injection of circular DNA molecules (plasmids) into nuclei of Pleurodeles waltlii oocytes; and (ii) by in vitro incubation of plasmid molecules with the supernatant fraction from oocyte nuclei of Pleurodeles and Xenopus laevis, followed by purification of nucleoprotein structures formed with sucrose gradient centrifugation. [n both types of experiments , spread preparations of the newly assembled and transcriptionally inactive chromatin , examined by electron microscopy , show dense globular higher order (supranucleosomal) packing forms. Under partially relaxing (low salt) preparation conditions granular chromatin subunits of about 30 nm diameter can be seen either as widely spaced particles or in closely packed aggregates. The transcriptionally inactive endogenous chromatin of chromomeres of lampbrush chromosomes is arranged in similar higher order chromatin units. A correlation is found between the sizes of the DN A molecule probes used and the numbers of nucleosomes and higher order globules in the assembled chromatin structures. After prolonged dispersion in low salt buffers , these globular chromatin units unfold into chains of7-12 nucleosomes. The results support the concept that chromatin is arranged , under physiological ion concentrations as they are present in the nucleus , in supranucleosomal units of globular morphology.
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39671
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - Structural organization of spacer chromatin between transcribed ribosomal RNA genes in amphibian oocytes
N2  - Transcribed nucleolar chomatin, including the spacer regions interspersed between the rRNA genes, is different from the bulk of nontranscribed chromatin in that the DNA of these regions appears to be in an extended (B) conformation when examined by electron microscopy. The possibility that this may reflect artificial unfolding of nucleosomes during incubation in very low salt buffers as routinely used in such spread preparations has been examined by studying the influence of various ion concentrations on nucleolar chromatin structure. Amplified nucleolar chromatin of amphibian oocytes (Xenopus laevis, Pleurodeles waltlii, Triturus cristatus) was spread in various concentrations of NaCl (range 0 to 20 mM). Below 1 mM salt spacer chromatin frequently revealed a variable number of irregularly shaped beads, whereas above this concentration the chromatin axis appeared uniformly smooth. At all salt concentrations studied, however, the length distribution of spacer and gene regions was identical. Preparations fixed with glutaraldehyde instead of formaldehyde, or unftxed preparations, were indistinguishable in this respect. The observations indicate that (i) rDNA spacer regions are not compacted into nucleosomal particles and into supranucleosomal structures when visualized at chromatin stabilizing salt concentrations (e.g., 20 mM NaCl), and (ii) spacer DNA is covered by a uniform layer of proteins of unknown nature which, at very low salt concentrations (below 1 mM NaCl), can artificially give rise to the appearance of small granular particles of approximately nucleosome-like sizes. These particles, however, are different from nucleosomes in that they do not foreshorten the associated spacer DNA. The data support the concept of an altered nucleohistone conformation not only in transcribed chromatin but also in the vicinity of transcriptional events.
KW  - Cytologie
KW  - Chromatin structure
KW  - rDNA
KW  - amphibian oocytes
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41057
ER  - 
TY  - JOUR
A1  - von Jagow, Gerhard
A1  - Sebald, Walter
T1  - b-Type cytochromes
N2  - No abstract available
KW  - Biochemie
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47383
ER  - 
TY  - JOUR
A1  - Sebald, Walter
A1  - Machleidt, Werner
A1  - Wachter, Elmar
T1  - N,N'-dicyclohexylcarbodiimide binds specifically to a single glutamyl residue of the proteolipid subunit of the mitochondrial adenosinetriphosphatases from Neurospora crassa and Saccharomyces cerevisiae
N2  - T~e N,N'-dicrclohexylcarbodiimide-binding proteolipid subumt of the mitochondrial adenosinetriphosphatases (ATP phosphohydrolase, EC 3.6.1.3) of Neurosporacrassa and Saccharomyces cerevisiae were purified from mitochondria incubated with the radioactively labeled inhibitor. The specifically labeled subunit was cleaved with cyanogen bromide and N-bromosuccinimide, and the resultant fragments were separated by gel chromatography in the presence of 80% (vol/vol) formic acid. The N,N'-dicyclohexylcarbodiimide label was recovered in each organism exclusively in a 17-residue fragment. Further analysis by automated solid-phase Edman degrada.ti.on revealed tha~ the bound label was present at only one positIOn, correspondmg to a glutamyl residue. The NN'~ icyc~ohexyl~a~bodiiJ?1~de-'!l0dified glutamyl residue is the ~nly Id~ntIcal aCidic posItIon m both proteins and occurs in the middle of a hydrophobic sequence of about 25 residues.
KW  - Dicyclohexylcarbodiimid
KW  - Aminosäuren
KW  - inhibition of H+ translocation
KW  - amino acid sequence
KW  - automated solid-phase Edman degradation
Y1  - 1980
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47394
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Zentgraf, Hanswalter
A1  - Sauer, Helmut W.
T1  - Different chromatin structures in Physarum polycephalum: a special form of transcriptionally active chromatin devoid of nucleosomal particles
N2  - Nonnucleolar chromatin from interphase nuclei of Physarum polycephalum plasmodia occurs in two different structural configurations as seen in electron microscopic spread preparations. While the majority of the chromatin is devoid of nascent ribonucleoprotein (RNP) fibrils and compacted into nucleosomal particles, a minor proportion (10- 20%) is organized differently and reveals a smooth contour. It is this form of smooth chromatin which is rich in transcription units (mean length: 1.36±0.21 11m). Only occasionally are solitary nascent RNP fibrils observed which are associated with beaded strands of chromatin. In transcribed smooth chromatin nucleosomal particles are not only absent from the transcription units but also from their nontranscribed flan king regions, indicating that this special structural aspect is not merely a direct consequence of the transcriptional process. The existence of ca. 10- 20% of Physarum chromatin in the smoothly contoured form is discussed in relation to reports of a preferential digestibility of a similar proportion of Physarum chromatin by DNAse I (Jalouzot et al. , 1980) and to the altered configuration of "peak A" chromatin subunits after micrococcal nuclease digestion (Johnson et al., 1978a, b).
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33148
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Sommerville, J.
T1  - Structural organization of nascent transcripts and hnRNA molecules in amphibian oocytes
N2  - Comparisons ofrelative lengths oflampbrush loops, nascent RNP transcripts and hnRNA molecules from oocytes of amphibia with different C-values show that there is an increasing trend in loop, and transcriptional unit, length with increase in genome size but no increasing trend with respect to RN A contour length.The formation of duplex regions and circles in RNP fibrils indicates that RNA processing may occur within the nascent fibrils. The hnRNA molecules from oocytes of the various amphibia readily form intermolecular duplex structures. These complementary sequences have a low kinetic complexity and are transcribed from highly repetitive sequences distributed throughout the genome. Their possible function is considered.
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39765
ER  - 
TY  - JOUR
A1  - Zentgraf, H.
A1  - Müller, U.
A1  - Scheer, Ulrich
A1  - Franke, W. W.
T1  - Evidence for the existence of globular units in the supranucleosomal organization of chromatin
N2  - No abstract available
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34123
ER  - 
TY  - JOUR
A1  - Bona, Marion
A1  - Scheer, Ulrich
A1  - Bautz, Ekkehard K. F.
T1  - Antibodies to RNA polymerase II (B) inhibit transcription in lampbrush chromosomes after microinjection into living amphibian oocytes
N2  - Antibodies directed against RNA polymerase II (B) from Drosophila melanogaster were obtained from rabbit sera and, as monoclonal immunoglobulins, from mouse hybridomas and shown to cross-react with the amphibian enzyme protein. Localization by indirect immunofluorescence microscopy revealed the association of this enzyme with chromatin of interphase nuclei of amphibian cells and its absence in nucleoli. Purified immunoglobulins were microinjected in to nuclei ofliving vitellogenic oocytes of Ple1lrodeles waltlii and X enopus laevis and their effects on transcriptional processes were monitored by biochemical and light and electron microscopic stud ies. RNA polymerase II antibodies from rabbit sera caused a rapid and almost complete release of nascent transcripts from the chromatin axis of the loops of lampbrush chromosomes, followed by collapse of the loops and their retraction on the main chromosome axis. Monoclonal murine antibodies to the Iarge RNA polymerase II subunits also inhibited transcription in chromosome Ioops but appeared to inhibit initiation rather than elongation events. Activities of class land III RNA polymerases were not significantly affected by injection of antibodies to polymerase II, indicating immunological differences between the three RNA polymerases. The potential value of the in vitro test system described , as a very sensitive assay for detecting proteins involved in transcription in living cells, is discussed. 1
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33128
ER  - 
TY  - JOUR
A1  - Franke, Werner W.
A1  - Scheer, Ulrich
A1  - Krohne, Georg
A1  - Jarasch, Ernst-Dieter
T1  - The nuclear envelope and the architecture of the nuclear periphery
N2  - No abstract available
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33108
ER  - 
TY  - JOUR
A1  - Franke, Werner W.
A1  - Kleinschmidt, Jürgen A.
A1  - Spring, Herbert
A1  - Krohne, Georg
A1  - Grund, Christine
A1  - Trendelenburg, Michael F.
A1  - Stöhr, Michael
A1  - Scheer, Ulrich
T1  - A nucleolar skeleton of protein filaments demonstrated in amplified nucleoli of Xenopus laevis
N2  - The amplified, extrachromosomal nucleoli of Xenopus oocytes contain a meshwork of -4-nm-thick filaments, which are densely coiled into higher-order fibrils of diameter 30-40 nm and are resistant to treatment with high- and low-salt concentrations, nucleases (DNase I, pancreatic RNase, micrococcal nuclease), sulfhydryl agents, and various nonionic detergents. This filamentous "skeleton" has been prepared from manually isolated nuclear contents and nucleoli as weil as from nucleoli isolated by fluorescence-activated particle sorting. The nucleolar skeletons are observed in light and electron microscopy and are characterized by ravels of filaments that are especially densely packed in the nucleolar cortex. DNA as weil as RNA are not constituents of this structure, and precursors to ribosomal RNAs are completely removed from the extraction-resistant filaments by treatment with high-salt buffer or RN ase. Fractions of isolated nucleolar skeletons show specific enrichment of an acidic major protein of 145,000 mol wt and an apparent pi value of -6.15, accompanied in some preparations by various amounts of minor proteins. The demonstration of this skeletal structure in "free" extrachromosomal nucleoli excludes the problem of contaminations by nonnucleolar material such as perinucleolar heterochromatin normally encountered in studies of nucleoli from somatic cells. It is suggested that this insoluble protein filament complex forms a skeleton specific to the nucleolus proper that is different from other extraction-resistant components of the nucleus such as matrix and lamina and is involved in the spatial organization of the nucleolar chromatin and its transcriptional products. In studies of the organization of the interphase nucleus, considerable progress has been made in the elucidation of the arrangement of chromatin components and transcriptional products. However, relatively little is known about the composition and function of another category of nuclear structures, the nonnucleoproteinaceous architectural components that are insoluble in solutions of low and high ionic strength, despite numerous studies dedicated to this problem. Such structures include (a) the nuclear envelope and its pore complexes (I, 15, 18, 23, 37, 41), (b) a peripheral layer of insoluble protein ("lamina"; I, 15, 22, 23, 59), (e) certain skeletal proteins related to the chromosome "scaffold" described by Laemmli and coworkers (see references 2 and 3), and (d) ill-defined tangles of fibrillar structures of the nuclear interior that are collectively described as residual "matrix" (6, 21 ; for reviews, see references THE JOURNAL OF CEll BrOlOGY . VOlUME 90 AUGUST 1981 289-299 © The RockefeIler University Press · 0021 -9525/ 81 / 08/ 0289/ 11 $1 .00 4 and 12). The latter, preparatively
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33130
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - Identification of a novel class of tandemly repeated genes transcribed on lampbrush chromosomes of Pleurodeles waltlii
N2  - Electron microscope preparations of lampbrush chromosomes from oocytes of Pleurodeles waltl;; have revealed a new class of tandemly repeated genes. These genes are highly active, as judged by the close spacing of nascent transcripts. They occur in clusters of >100 copies and are transcribed in units containing roughly 940 base pairs of DNA that are separated by nontranscribed spacers of an estimated DNA content of 2,410 base pairs. The size and the pattern of arrangement of these transcription units can not be correlated with any of the repetitious genes so far described.
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33153
ER  - 
TY  - JOUR
A1  - Werner, S.
A1  - Sebald, Werner
T1  - Immunological techniques for studies on the biogenesis of mitochondrial membrane proteins
N2  - no abstract available
KW  - Biochemie
Y1  - 1981
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82044
ER  - 
TY  - JOUR
A1  - Schairer, H. U.
A1  - Hoppe, J.
A1  - Sebald, Walter
A1  - Friedl, P.
T1  - Topological and functional aspects of the proton conductor, F\(_0\), of the Escherichia coli ATP-synthase
N2  - The isolated H\(^+\) conductor, F\(_0\) , of the Escherichia co1i ATP-synthase consists of three subunits, a, b, and c. H\(^+\) -permeable liposomes can be reconstit~ted with F\(_0\) and lipids; addition of F\(_1\)-ATPase reconstitutes a functional ATP-synthase. Mutants with altered or misslng F\(_0\) subunits are defective in H\(^+\) conduction. Thus, all three subunits are necessary for the expression of H\(^+\) conduction. The subunits a and b contain binding sites for F\(_1\)• Computer calculations, cross-links, membrane-permeating photo-reactive labels, and proteases were used to develop tentative structural models for the individual F\(_0\) subunits.
KW  - Biochemie
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62721
ER  - 
TY  - JOUR
A1  - Sebald, Walter
A1  - Friedl, P.
A1  - Schairer, H. U.
A1  - Hoppe, J.
T1  - Structure and genetics of the H\(^+\)-conducting F\(_0\) portion of the ATP synthase
N2  - The ATP synthase occurs in remarkably conserved form in procaryotic and eucaryotic cells. Thus, our present knowledge of ATP synthase is derived from sturlies of the enzyme from different organisms, each affering specific experimental possibilities. In recent tim es, research on the H\(^+\) -conducting F0 part of the ATP synthase has been greatly stimulated by two developments in the Escherichio coli system. Firstly, the purification and reconstitution of the whole ATP synthase as weil as the proton conductor Fa from E. coli have been achieved. These functionally active preparations are well defined in terms of subunit composition, similar to the thermophilic enzyme from PS-3 studied by Kagawa's group.u Secondly, the genetics and the molecular cloning of the genes of all the F\(_0\) subunits from E. coli yielded information on the function of subunit polypeptides and essential amino acid residues. Furthermore, the amino acid sequence of hydrophobic F\(_0\) subunits, which are difficult to analyze by protein-chemical techniques, could be derived from the nucleotide sequence of the genes. These achievements, which shall be briefly summarized in the next part of this communication, provide the framework to study specific aspects of the structure and function of the F\(_0\) subunits.
KW  - Biochemie
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62733
ER  - 
TY  - JOUR
A1  - Viebrock, A.
A1  - Perz, A.
A1  - Sebald, Walter
T1  - The imported preprotein of the proteolipid subunit of the mitochondrial ATP synthase from Neurospora crassa. Molecular cloning and sequencing of the mRNA
N2  - No abstract available
KW  - Biochemie
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62742
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Barnekow, A.
A1  - Bauer, H.
A1  - Anders, F.
T1  - Correlations of inheritance and expression between a tumor gene and the cellular homolog of the Rous sarcoma virus-transforming gene in Xiphophorus
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61937
ER  - 
TY  - JOUR
A1  - Barnekow, A.
A1  - Schartl, Manfred
A1  - Anders, F.
A1  - Bauer, H.
T1  - Identification of a fish protein associated with a kinase activity and related to the Rous sarcoma virus transforming protein
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61946
ER  - 
TY  - JOUR
A1  - Kreft, Jürgen
A1  - Hughes, Colin
T1  - Cloning vectors derived from plasmids and phage of Bacillus
N2  - No abstract available
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-47014
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - A novel type of chromatin organization in lampbrush chromosomes of Pleurodeles waltlii: visualization of clusters of tandemly repeated, very short transcriptional units
N2  - A novel chromatin configuration is described in lampbrush chromosomes of Pleurodeles waltlii oocytes which is different from transcriptionally inactive chromatin as weil as from the various forms of transcribed chromatin hitherto described. This novel type of chromatin is not arranged in Christmas tree-Iike configurations of densely packed lateral ribonucleoprotein (RNP) fibriIs but is characterized by a periodic alternating pattern of thick and thin regions which occur in clusters 01 some 10,000 repeats. Each thickened unit with an average length of 45 nm contains two c10sely spaced particles, the putative RNA polymerases, and each thickened unit is separated from the next one by a beaded chromatin spacer with a length of about 80 nm. This chromatin spacer contains on average two particles of approximately 14 nm in diameter, assumed to be nucleosomes. The thickened regions are interpreted to represent short transcriptional units containing approximately 130 base pairs of DNA which are separated from each other by nontranscribed spacers of 240-400 base pairs of DNA. The possibility is discussed that these transcriptional units represent 5S rRNA or tRNA genes.
KW  - Lampbrush chromosomes
KW  - Amphibian oocytes
KW  - Transcription units
KW  - Electron microscopy
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41087
ER  - 
TY  - JOUR
A1  - Sommerville, John
A1  - Scheer, Ulrich
T1  - Transcription of complementary repeat sequences in amphibian oocytes
N2  - Repeat sequences are transcribed in the germinal vesicles of amphibian oocytes. In the hnRNA population both complements of the repeats are found and can be readily detected because they form intermolecular duplex structures. The structure and formation of duplex regions have been studied in the hnRNA of Xenopus laevis, Triturus cristatus, Amphiuma means and Necturus maculosus, a series of amphibians of increasing genome size (C-value). In T. cristatus, the duplex structures are mostly 600- 1200 bp in length, whereas in X. laevis they are shorter and in N. maculosus they tend to be longer. Although the proportion of RNA sequence capable of rapidly forming duplex structures is different in different organisms, this property bears no relationship to C-value. However the sequence complexity of complementary repeats, as estimated from the rate of duplex formation, does show an increasing trend with C-value. The complementary repeats found in oocyte hnRNA are transcribed from families of DNA sequence that are each represented in the genome by thousands of copies. The extent of cross-species hybridization is low, indicating that the repeat sequences transcribed in different amphibian genera are not the same. In situ hybridization experiments indicate that the repeat sequences are spread throughout the genome. The evolution and possible function of complementary repeats are considered.
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33915
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - Biologische Objekte im Transmissions-Elektronenmikroskop (Teil 4): Spreitungstechniken
N2  - Visualizing nucleic acids (DNA, RNA), nucleoprotein complexes and chromatin requires the use of special electron microscopicspreading techniques. In part 4 (27 refs.), methods are outlined for spreading DNA and RNA molecules for electron microscopic observation, these methods using modifications of the basic protein film method developed by A. Kleinschmidt and R. K. Zahn (1959). Hybridization techniques that allow the observation of heteroduplexes formed between two DNA molecules or between DNA and RNA molecules are reviewed, with special emphasis being placed on the DNA-RNA hybrids as a tool for elucidating RNA splicing. Techniques for studying DNA-protein interactions without the use of a protein monolayer film are mentioned. Finally, the "Miller spreading technique" for visualizing the nucleosomal organization of eukaryotic chromatin as well as the transcription of genes is discribed and illustrated.
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39652
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Sommerville, John
T1  - Sizes of chromosome loops and hnRNA molecules in oocytes of amphibia of different genome sizes
N2  - The lengths of lampbrush chromosome loops and their tran scription units show a positive correlation with genome size in oocytes of amphibia with different C values. However, there is no such correlation with contour lengths of hnRNA molecu les isolated from these oocytes. These results indi cate th at more ON A sequences are transcribed in amphibia of higher C value , but that processing of RNA transc ripts occurs while they are still attached to the chromosomes as nascent ribonucleoprotein fibrils.
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33094
ER  - 
TY  - JOUR
A1  - Moreno-Diaz de la Espina, Susana
A1  - Franke, Werner W.
A1  - Krohne, Georg
A1  - Trendelenburg, Michael F.
A1  - Grund, Christine
A1  - Scheer, Ulrich
T1  - Medusoid fibril bodies: a novel type of nuclear filament of diameter 8 to 12 nm with periodic ultrastructure demonstrated in oocytes of Xenopus laevis
N2  - No abstract available
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34116
ER  - 
TY  - JOUR
A1  - Schartl, A.
A1  - Schartl, Manfred
A1  - Anders, F.
T1  - Promotion and regression of neoplasia by testosterone-promoted cell differentiation in Xiphophorus and Girardinus
N2  - No abstract available.
KW  - Schwertkärpfling
KW  - Lebendgebärende Zahnkarpfen
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86684
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Barnekow, Angelika
T1  - The expression in eukaryotes of a tyrosine kinase which is reactive with pp60v-src antibodies
N2  - All specimens of Eumetazoa and Parazoa, ranging from mammals, birds, teleosts, sharks, lampreys, amphioxus, insects, down to sponges showed the pp60c-src associated kinase activity, indicating that c-src, which is the cellular homologue of the oncogene v-src of Rous sarcoma virus (RSV) is probably present in all multicellular animals. Protozoa and plants did not show pp60c-src: kinase activity.
The degree of c-src expression depends on the taxonomic rank of the Eumetazoa tested, and is organ-specific with nervaus tissues displaying the highest kinase activities. In the central nervous system of mammals and birds we found a high c-src expression, and in that of the lampreys, amphioxus, and insects the lowest. Unexpectedly, total extracts of sponges showed an amount of pp60c-src kinase activity similar to that of brain cell extracts of mammals and birds. These findings suggest that pp60c-src is a phylogenetic old protein that might have evolved together with the multicellular organisation of Metazoa, and that might be of importance in proliferation and differentiation of nontransformed cells.
KW  - Protein-Tyrosin-Kinasen
KW  - Eukaryoten
Y1  - 1982
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86208
ER  - 
TY  - JOUR
A1  - Hoppe, J.
A1  - Friedl, P.
A1  - Schairer, H. U.
A1  - Sebald, Walter
A1  - Meyenburg, K. von
A1  - Jorgensen, B. B.
T1  - The topology of the proton translocating F\(_0\) component of the ATP synthase from E. coli K12: studies with proteases
N2  - The accessibility of the three F\(_0\) subunits a, b and c from the Escherichia coli Kll A TP synthase to various proteases was studied in F\(_1\)-depleted inverted membrane vesicles. Subunit b was very sensitive to all applied proteases. Chymotrypsin produced a defined fragment of mol. wt. 1S 000 which remained tightly bound to the membrane. The cleavage site was located at the C-terminal region of subunit b. Larger amounts of proteases were necessary to attack subunit a (mol. wt. 30 000). There was no detectable deavage of subunit c. It is suggested that the major hydrophilic part of subunit b extends from the membrane into the cytoplasm and is in contact with the F\(_1\) sector. The F\(_1\) sector was found to afford some protection against proteolysis oftheb subunit in vitro andin vivo. Protease digestion bad no influence on the electro-impelled H\(^+\) conduction via F\(_0\) bot ATP-dependent H\(^+\) translocation could not be reconstituted upon binding of F\(_1\)• A possible role for subunit b as a linker between catalytic events on the F\(_1\) component and the proton pathway across the membrane is discussed.
KW  - Biochemie
KW  - protein pathway
KW  - ATPase mutants
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62718
ER  - 
TY  - JOUR
A1  - Kreft, Jürgen
A1  - Burger, Klaus J.
A1  - Goebel, Werner
T1  - Expression of antibiotic resistance genes from Escherichia coli in Bacillus subtilis
N2  - Bifunctional recombinant plasmids were constructed, comprised of the E. coli vectors pBR322, pBR325 and pACYC184 and different plasmids from Gram-positive bacteria, e.g. pBSU161-1 of B. subtilis and pUB110 and pC221 of S. aureus. The beta-lactamase (bla) gene and the chloramphenicol acetyltransferase (cat) gene from the E. coli plasmids were not transcribed and therefore not expressed in B. subtilis. However, tetracycline resistance from the E. coli plasmids was expressed in B. subtilis. Transcription of the tetracycline resistance gene(s) started in B. subtilis at or near the original E. coli promoter, the sequence of which is almost identical with the sequence recognized by σ<sup>55</sup> of B. subtilis RNA polymerase.
KW  - Biologie
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60600
ER  - 
TY  - JOUR
A1  - Kreft, Jürgen
A1  - Berger, Harald
A1  - Härtlein, Michael
A1  - Müller, Bodo
A1  - Weidinger, Gerhard
A1  - Goebel, Werner
T1  - Cloning and expression in Escherichia coli and Bacillus subtilis of the hemolysin (cereolysin) determinant from Bacillus cereus
N2  - From a cosmid gene bank of Bacillus cereus GP4 in Escherichia coli we isolated clones which, after several days of incubation, formed hemolysis zones on erythrocyte agar plates. These clones contained recombinant cosmids with B. cereus DNA insertions of varying lengths which shared some common restriction fragments. The smallest insertionwas recloned as aPstl fragment into pJKK3-1, a shuttle vector which repücates in Bacillus subtilis and E. coli. When this recombinant plasmid (pJKK3-1 hly-1) was transformed into E. coli, it caused hemolysis on erythrocyte agar plates, but in liquid assays no extemal or intemal hemolytic activity could be detected with the E. coli transformants. B. subtilis carrying the same plasmid exhibited hemolytic activity at Ievels comparable to those ofthe B. cereus donor strain. The hemolysin produced in B. subtilis seemed to be indistinguishable from cereolysin in its sensitivity to cholesterol, activation by dithiothreitol, and inactivation by antibodies raised against cereolysin. When the recombinant DNA carrying the cereolysin gene was used as a probe in hybridization experiments with chromosomal DNA from a streptolysin 0-producing strain of Streptococcus pyogenes or from üsteriolysin-producing strains of Usteria monoeytogenes, no positive hybridization signals were obtained. These data soggest that the genes for these three SH-activated cytolysins do not have extended sequence homology.
KW  - Biologie
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60596
ER  - 
TY  - JOUR
A1  - Härtlein, Michael
A1  - Schiessl, Sigrid
A1  - Wagner, Wilma
A1  - Rdest, Ursula
A1  - Kreft, Jürgen
A1  - Goebel, Werner
T1  - Transport of hemolysin by Escherichia coli
N2  - No abstract available
KW  - Biologie
KW  - Hemolysin
KW  - Escberichia coli
KW  - Gene cloning
KW  - Expression
KW  - Transport
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60619
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Lanfranchi, Gerolamo
A1  - Rose, Kathleen M.
A1  - Franke, Werner W.
A1  - Ringertz, Nils R.
T1  - Migration of rat RNA polymerase I into chick erythrocyte nuclei undergoing reactivation in chick-rat heterokaryons
N2  - Transcriptionally inactive chick erythrocyte nudei were reactivated by Sendai virusinduced fusion of erythrocytes with rat L6j1 myoblasts. We used antibodies to trace the appearance of a specific protein engaged in transcription of a defined dass of genes, those coding for rRNA, during reactivation. Using immunofluorescence microscopy, we found increasing amounts of rat RNA polymerase I to appear, during a certain period of time after fusion, in the reforming nudeoli of the chick nudei. Amounts of rat RNA polymerase I sufficient to be detected by immunofluorescence microscopy had accumulated in the newly developed chick nudeoli 72- 190 h after fusion was initiated. This time interval coincides with the time when chick rRNA synthesis can first be detected. The results raise the possibility that during these stages of the reactivation process chick rRNA genes are transcribed by heterologous RNA polymerase I moleeules of rat origin.
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33232
ER  - 
TY  - JOUR
A1  - Kleinschmidt, Jürgen A.
A1  - Scheer, Ulrich
A1  - Dabauvalle, Marie-Christine
A1  - Bustin, Michael
A1  - Franke, Werner W.
T1  - High mobility group proteins of amphibian oocytes: a large storage pool of a soluble high mobility group-1-like protein and involvement in transcriptional events
N2  - No abstract available
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33250
ER  - 
TY  - JOUR
A1  - Viebrock, A
A1  - Perz, A
A1  - Sebald, Walter
T1  - Molecular cloning of middle-abundant mRNAs from Neurospora crassa
N2  - no abstract available
KW  - Neurospora crassa
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82033
ER  - 
TY  - JOUR
A1  - Gessler, Manfred
A1  - Barnekow, Angelika
T1  - Differential expression of the cellular oncogenes c-src and c-yes in embryonal and adult chicken tissues
N2  - The cellular onc-genes c-src and c-yes are expressed very differently during chicken embryonic development. The c-src mRNA and its translational product are detectable at high levels in brain extracts of chicken embryos and adult chickens, whereas muscle extracts show an age-dependent decrease in the amounts of c-src-specific mRNA and pp60<sup>c-src</sup> kinase activity. In contrast, the Ievels of c-yes mRNA in brain, heart, and muscle are relatively low in early embryonic stages and increase later on to values comparable to those found for liver, while in adult animals the pattern of c-yes expression is similar to that of the c-src gene. From the close correlation between the Ievels of pp60<sup>c-src</sup>, its enzymatic activity, and its corresponding mRNA at a given stage of development and in given tissues, it appears that the expression of pp60<sup>c-src</sup> is primarily controlled at the level of transcription. It is suggested that because of the different patterns of expression, the two cellular oncogenes, c-src and c-yes, play different roles in cell proliferation during early embryonic stages as weil as in ensuing differentiation processes.
KW  - Biochemie
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59289
ER  - 
TY  - JOUR
A1  - Arends, H.
A1  - Sebald, Walter
T1  - Nucleotide sequence of the cloned mRNA and gene of the ADP/ATP carrier from Neurospora crassa
N2  - A cDNA complementary to the mRNA of the ADPIATP carrier from Neurospora crassa was identified among ordered cDNA clones by hybridizing total polyadenylated RNA to pools of 96 cDNA recombinant plasmids and subsequent cellfree translation of hybridization-selected mRNA. Further carrier cDNAs were found by colony fdter hybridization at a frequency of 0.2-0.3%. The gene of the carrier was cloned and isolated on a 4.6-kbp EcoRl fragment of total Neurospora DNA, and the start of the mRNA was determined by Sl nuclease mapping. From the nucleotide sequence of the cDNA and the genomic DNA, the primary structure of the gene, of the mRNA and of the ADP I ATP carrier protein could be deduced. The gene occurs in a single copy in the genome and related genes are absent. It contains two short introns, and a pyrimidine-rieb promoter region. The mRNA has a 46-bp 5 1 end and a 219-bp 3 1 end. There is an open reading frame coding for the 313 amino acid residues of the Neurospora carrier protein. The amino acid sequence is homologous in 148 positions with the established primary structure of the beef heart carrier.
KW  - Biochemie
KW  - mitochondrial ADP
KW  - ATP carrier
KW  - Neurospora crassa
KW  - mRNA and gene
KW  - nucleotide sequence
KW  - hybrid-selected translation
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62684
ER  - 
TY  - JOUR
A1  - Velours, J.
A1  - Esparza, M.
A1  - Hoppe, J.
A1  - Sebald, Walter
A1  - Guerin, B.
T1  - Amino acid sequence of a new mitochondrially synthesized proteolipid of the ATP synthase of Saccharomyces cerevisiae
N2  - The purification and the amino acid sequence of a proteolipid translated on ribosomes in yeast mitochondria is reported. This protein, which is a subunit of the A TP synthase, was purified by extraction with chloroform/methanol (2/1) and subsequent chromatography on phosphocellulose and reverse phase h.p.l.c. A mol. wt. of 5500 was estimated by chromatography on Bio-Gel P-30 in 8011/o fonnie acid. The complete amino acid sequence of this protein was determined by automated solid phase Edman degradation of the whole protein and of fragments obtained after cleavage with cyanogen bromide. The sequence analysis indicates a length of 48 amino acid residues. The calculated mol. wt. of 5870 corresponds to the value found by gel chromatography. This polypeptide contains three basic residues and no negatively charged side chain. The three basic residues are clustered at the C terminus. The primary structure of this protein is in full agreement with the predicted amino acid sequence of the putative polypeptide encoded by the mitochondrial aap1 gene recently discovered in Saccharomyces cerevisiae. Moreover, this protein shows 5011/o homology with the amino acid sequence of a putative polypeptide encoded by an unidentified reading frame also discovered near the mitochondrial ATPase subunit 6 genein Aspergillus nidulans.
KW  - Biochemie
KW  - ATP synthase
KW  - mitochondrially translated
KW  - proteolipid
KW  - sequence subunit
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62695
ER  - 
TY  - JOUR
A1  - Schmidt, B.
A1  - Wachter, E.
A1  - Sebald, Walter
A1  - Neupert, W.
T1  - Processing peptidase of Neurospora mitochondria. Two-step cleavage of imported ATPase subunit 9
N2  - Subunit 9 (dicyclohexylcarbodümide binding protein, 'proteolipid') of the mitochondrial F 1F0-ATPase is a nuclearly coded protein in Neurospora crassa. lt is synthesized on free cytoplasmic ribosomes as a larger precursor with an NH2-terminal peptide extension. The peptide extension is cleaved ofT after transport of the protein into the mitochondria. A processing activity referred to as processing peptidase that cleaves the precursor to subunit 9 and other mitochondrial proteins is described and characterized using a cell-free system. Precursor synthesized in vitro was incubated with extracts of mitochondria. Processing peptidase required Mn2 + for its activity. Localization studies suggested that it is a soluble component of the mitochondrial matrix. The precursor was cleaved in two sequential steps via an intermediate-sized polypeptide. The intermediate form in the processing of subunit 9 was also seen in vivo and upon import of the precursor into isolated mitochondria in vitro. The two dcavage sites in the precursor molecule were determined. The data indicate that: {a) the correct NH2-terminus of the mature protein was generated, (b) the NH2-terminal amino acid of the intermediate-sized polypeptide is isoleueine in position -31. The cleavage sites show similarity ofprimary structure. It is concluded that processing peptidase removes the peptide extension from the precursor to subunit 9 (and probably other precursors) after translocation of these polypeptides (or the NHrterminal part of these polypeptides) into the matrix space of mitochondria.
KW  - Biochemie
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62674
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Barnekow, A.
T1  - Differential expression of the cellular src gene during vertebrate development
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61893
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Barnekow, A.
T1  - Cellular src gene product detected in the freshwater sponge Spongilla lacustris
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61904
ER  - 
TY  - JOUR
A1  - Riehl, R.
A1  - Schartl, Manfred
T1  - A Transmission Electron Microscopical and Freeze-Etch Study of Malignant-Melanoma in Fish
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61916
ER  - 
TY  - JOUR
A1  - Riehl, R.
A1  - Schartl, Manfred
A1  - Kollinger, G.
T1  - Comparative studies on the ultrastructure of malignant melanoma in fish and human by freeze-etching and transmission electron microscopy
N2  - Malignant melanomas (MM) in the fish Xiphophorus and in humans were studied both by transmission electron microscopy (TEM) and freeze-etching (FE). In both fish and human melanomas the cells show interdigitations of the,plasma membranes. The nuclei are large and lobulated and have many nuclear pores. Melanosomes are abundant and melanosome complexes ("compound melanosomes") occur regularly. Pinocytotic vesicles could be demonstrated in fish and human melanomas showing iocal differences in frequency and distribution patterns in the tumor. lntercellular junctions are lacking in MM cells from fish and humans. The FE technique showed considerable advantages in demonstrating membrane-surface peculiarities such as nuclear pores or pinocytotic vesicles. The FE replicas of fish melanomas are like those of humans. These findings may support the hypothesis that melanoma in fish and humans reflect the same biological phenomenon.
KW  - Physiologische Chemie
KW  - Malignant melanoma
KW  - Fish
KW  - Human
KW  - Freeze-etching
KW  - Transmission electron microscopy
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61920
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Schmidt-Zachmann, Marion S.
A1  - Hügle, Barbara
A1  - Franke, Werner W.
T1  - Identification and localization of a novel nucleolar protein of a high molecular weight by a monoclonal antibody
N2  - A monoclonal murine antibody (No-I 14) is described which reacts specifically with a polypeptide of molecular weight (M,) 180000 present in low-speed nuclear pellets from oocytes and somatic cells of Xenopus laevis and X. borealis and in isolated amplified nucleoli. Two-dimensional gel electrophoresis has revealed the acidic nature of this polypeptide (isoelectric at pH of ca 4.2 in the presence of 9.5 M urea). A relatively large proportion of the protein is extracted at elevated ionic strength( i.e., at 0.4-0.5 M alkali salt) in a form sedimenting at approx. 7-8S , compatible with a monomeric state. It is also extracted by digestion with RNase but not with DNase. In immunofluorescence microscopy, antibody No-114 stains intensely nucleoli of oocytes and all somatic cells examined , including the residual nucleolar structure of Xenopus erythrocytes which are transcriptionally inactive. During mitosis the antigen does not remain associated with the nucleolar organizer regions (NOR) of chromosomes but is released and dispersed over the cytoplasm until telophase when it re-associates with the reforming interphase nucleoli. At higher resolution the immunofluorescent region is often resolved into a number of distinct subnucleolar components of varied size and shape. Immunoelectron microscopy using colloidal gold-coupled secondary antibodies reveals that the M, 180000 protein is confined to the dense fibrillar component of the nucleolus. This conclusion is also supported by its localization in the fibrillar part of segregated nucleoli of cells treated with actinomycin D. We conclude that nucleoli contain a prominent protein of M, 180000 which contributes to the general structure of the dense fibrillar component of the interphase nucleolus , independent of its specific transcriptional activity.
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39786
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Hinssen, Horst
A1  - Franke, Werner W.
A1  - Jockusch, Brigitte M.
T1  - Microinjection of actin-binding proteins and actin antibodies demonstrates involvement of nuclear actin in transcription of lampbrush chromosomes
N2  - Nuclei of amphibian oocytes contain large amounts of actin, mostly in unpolymerized or short-polymer form. When antibodies to actin or actin-binding proteins (fragmin and the actin modulator from mammalian smooth muscle) are injected into nuclei of living oocytes of Pleurodeles waltlii, transcription of the lampbrush chromosomes, but not of the rRNA genes, is inhibited. When transcription is repressed by drugs or RNA is digested by microinjection of RNAase into oocyte nuclei, an extensive meshwork of actin filament bundles is seen in association with the isolated lampbrush chromosomes. These observations indicate a close relationship between the state of nuclear actin and transcriptional activity and suggest that nuclear actin may be involved in transcriptional events concerning protein-coding genes.
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39706
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Hügle, Barbara
A1  - Hazan, Rachel
A1  - Rose, Kathleen M.
T1  - Drug-induced dispersal of transcribed rRNA genes and transcriptional products: Immunolocalization and silver staining of different nucleolar components in rat cells treated with 5,6-dichloro-1-Beta-D-ribofuranosylbenzimidazole
N2  - Upon incubation of cultured rat cells with the adenosine analogue 5,6-dichloro-l-&#946;- D-ribofuranosylbenzimidazole (DRB), nucleoli reversibly dissociate into their substructures, disperse throughout the nuclear interior, and form nucleolar "necklaces". We have used this experimental system, which does not inhibit transcription of the rRNA genes, to study by immunocytochemistry the distribution of active rRNA genes and their transcriptional products during nucleolar dispersal and recovery to normal morphology. Antibodies to RNA polymerase I allow detection of template-engaged polymerase, and monoclonal antibodies to a ribosomal protein (S 1) of the small ribosomal subunit permit localization of nucleolar preribosomal particles. The results show that, under the action of DRB transcribed rRNA, genes spread throughout the nucleoplasm and finally appear in the form of several rows, each containing several (up to 30) granules positive for RNA polymerase land argyrophilic proteins. Nucleolar material containing preribosomal particles also appears in granular structures spread over the nucleoplasm but its distribution is distinct from that of rRNA gene-containing granules. We conclude that, although transcriptional units and preribosomal particles are both redistributed in response to DRB, these entities retain their individuality as functionally defined subunits. We further propose that each RNA polymerase-positive granular unit represents a single transcription unit and that each continuous array of granules ("string of nucleolar beads") reflects the linear distribution of rRNA genes along a nucleolar organizer region. Based on the total number of polymerase I-positive granules we estimate that a minimum of 60 rRNA genes are active during interphase of DRB-treated rat cells.
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33216
ER  - 
TY  - JOUR
A1  - Linsenmair, Karl Eduard
T1  - Comparative studies on the social behaviour of the desert isopod Hemilepistus reaumuri and of a Porcellio species
N2  - Behavioural adaptations have made the desert isopod Hemilepistus reaumuri the most successful herbivore and detritivore of the macrofauna of many arid areas in North Africa and Asia Minor. For survival and reproduction Hemilepistus is dependent on burrows. New burrows can only be dug during spring. With the time-consuming digging of a burrow, Hemilepistus has only made the first step towards solving its ecological problems. The burrows are vital and have to be continuously defended against competitors. This requirement is met by co-operation of individuals within the framework of a highly developed social behaviour. In spring adults form monogamous pairs in which partners recognize each other individually and later form, with their progeny, strictly closed family communities. Hemilepistus is compared with a Porcellio' sp. which has developed, convergently, a social behaviour which resembles that of Hemilepistus in many respects, but differs essentially in some aspects, partly reflecting differences in ecological requirements. This and a few other Porcellio species demonstrate some possible steps in the evolution of the social behaviour of Hemilepistus. The female Hemilepistus is-in contrast to Porcellio sp. - semelparous and the selective advantages of monogamy in its environment are not difficult to recognize. This chapter discusses how this mating system could have evolved and especially why monogamous behaviour is also the best method for the Hemilepistus male to maximize its reproductive success. The cohesion of pairs and of family communities in Hemilepistus is based on a highly developed chemical communication system. Individual- and family-specific badges owe their specificity to genetically determined discriminating substances. The nature of the badges raises a series of questions: e.g. since alien badges release aggression, how do parents avoid cannibalizing their young? Similar problems arise from the fact that family badges are mixtures of chemical compounds of very low volatility with the consequence that they can only be transferred by direct contact and that during moulting all substances are lost which an individual does not produce itself. It is shown that in solving these problems inhibiting properties (presumably substances) and learning play a dominant role.
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30846
ER  - 
TY  - JOUR
A1  - Anders, F.
A1  - Schartl., Manfred
A1  - Barnekow, A.
A1  - Anders, A.
T1  - Xiphophorus as an in vivo model for studies on normal and defective control of oncogenes
N2  - The Xiphophorus tumor system has provided the opportunity to reduce the enormous complexity of cancer etiology to a few biological elements basically involved in neoplasia. The development of a tumor requires an oncogene which, after impairment, deletion, or elimination of its regulatory genes is permitted to mediate neoplastic transformation. Emphasis is being placed today in cancer research on the actual oncogenes themselves, but, in our opinion, the most important genes involved in neoplasia are these regulatory genes. However, although detected by c1assical genetics in the Xiphophorus system, th ese genes are not at present open to a more fin ely detailed molecular biological analysis. Their actual mode of action is therefore still far from being understood.
KW  - Xiphophorus
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80721
ER  - 
TY  - JOUR
A1  - Meyer, Manfred K.
A1  - Schartl, Manfred
T1  - Pseudotropheus (Maylandia) hajomaylandi n. sp., a new taxon from Lake Malawi
T1  - Pseudotropheus (Maylandia) hajomaylandi n. sp. un nouveau taxon du Lac Malawi
N2  - Pseudotropheus hajomaylandi (loc. typ. Isle of Chisumulu, Lake Malawi) is described as a new species. It is compared with Ps. aurora, Ps. greshakei, Ps. livingstonii, Ps. lombardoi, and Ps. zebra. All these taxa, including  Ps. hajomaylandi and Ps. heteropictus, are classified in the subgenus Maylandia.
KW  - Buntbarsche
KW  - Njassasee
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-70989
ER  - 
TY  - JOUR
A1  - Franke, Werner W.
A1  - Scheer, Ulrich
A1  - Zentgraf, Hanswalter
T1  - Organization of transcriptionally active and inactive chromatin
N2  - No abstract available
KW  - Deutschland
KW  - Gefäßpflanzen
KW  - Verzeichnis
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40588
ER  - 
TY  - JOUR
A1  - Hoppe, J.
A1  - Sebald, Walter
T1  - The proton conducting F0-part of bacterial ATP synthases
N2  - No abstract available
KW  - Biologie
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82019
ER  - 
TY  - JOUR
A1  - Sebald, Walter
A1  - Arends, Hermann
A1  - McCarthy, John E. G.
T1  - Isolation and manipulation of genes coding for energy-transducing enzymes from Neurospora crassa and Escherichia coli
N2  - No abstract available.
KW  - Escherichia coli
KW  - Neurospora crassa
Y1  - 1984
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86768
ER  - 
TY  - JOUR
A1  - Harnisch, U.
A1  - Weiss, H.
A1  - Sebald, Walter
T1  - The primary structure of the iron-sulfur subunit of ubiquinol-cytochrome c reductase from Neurospora, determined by cDNA and gene sequencing
N2  - No abstract available
KW  - Biochemie
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62631
ER  - 
TY  - JOUR
A1  - Gabellini, N.
A1  - Harnisch, U.
A1  - McCarthy, J. E.
A1  - Hauska, G.
A1  - Sebald, Walter
T1  - Cloning and expression of the fbc operon encoding the FeS protein, cytochrome b and cytochrome c\(_1\) from the Rhodopseudomonas sphaeroides b/c\(_1\) complex
N2  - The gene for the FeS protein of the Rhodopseudomonas sphaeroides b/c1 complex was identified by means of crosshybridization with a segment of the gene encoding the corresponding FeS protein of Neurospora crassa. Plasmids (pRSF1-14) containing the cross-hybridizing region, covering in total 13.5 kb of chromosomal DNA, were expressed in vitro in a homologous system. One RSF plasmid directed the synthesis of all three main polypeptides of the R. sphaeroides blc1 complex: the FeS protein, cytochrome b and cytochrome c1• The FeS protein and cytochrome c1 were apparently synthesized as precursor fonns. None of the pRSF plasmids directed the synthesis of the 10-kd polypeptide found in b/c1 complex preparations. Partial sequencing of the cloned region was performed. Several sites of strong homology between R. sphaeroides and eukaryotic polypeptides of the b/c1 complex were identified. The genes encode the three b/c1 polypeptides in the order: (5') FeS protein, cytochrome b, cytochrome c1• The three genes are transcribed to give a polycistronic mRNA of 2.9 kb. This transcriptional unit has been designated the jbc operon; its coding capacity corresponds to the size of the polycistronic mRNA assuming that only the genes for the FeS protein (jbcF), cytochrome b (jbcß) and cytochrome c1 (jbcC) are present. This could indicate that these three subunits constitute the minimal catalytic unit of the b/c1 complex from photosynthetic membranes.
KW  - Biochemie
KW  - R. sphaeroidesl
KW  - b/c1 complex
KW  - gene
KW  - cloning
KW  - in vitro expression
KW  - polycistronic mRNA
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62642
ER  - 
TY  - JOUR
A1  - McCarthy, J. E.
A1  - Schairer, H. U.
A1  - Sebald, Walter
T1  - Translational initiation frequency of atp genes from Escherichia coli: identification of an intercistronic sequence that enhances translation
N2  - The c, b and ö subunit genes of the Escherichia coli atp operon were cloned individually in an expression vector between the tac fusion promoter and the galK gene. The relative rates of subunit synthesis directed by the cloned genes were similar in vitro andin vivo and compared favourably with the subunit stoichiometry of the assembled proton-translocating A TP synthase of E. coli in vivo. The rate of synthesis of subunit c was at least six times that of subunit b and 18 times that of subunit ö. Progressive shortening of the long intercistronic sequence lying upstream of the subunit c gene showed that maximal expression of this gene is dependent upon the presence of a sequence stretching > 20 bp upstream of the Shine-Dalgarno site. This sequence thus acts to enhance the rate of translational initiation. The possibility that similar sequences might perform the same function in other operons of E. coli and bacteriophage A is also discussed. Translation of the subunit b cistron is partially coupled to translation of the preceding subunit c cistron. In conclusion, the expression of all the atp operon genes could be adjusted to accommodate the subunit requirements of A TP synthase assembly primarily by means of mechanisms which control the efficiency of translational initiation and re-initiation at the respective cistron start codons.
KW  - Biochemie
KW  - E. coli atp operon
KW  - subunit stoichiometry
KW  - in vitro and in vivo expression
KW  - translational initiation
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62657
ER  - 
TY  - JOUR
A1  - Lindenmaier, W.
A1  - Dittmar, K. E.
A1  - Hauser, H.
A1  - Necker, A.
A1  - Sebald, Walter
T1  - Isolation of a functional human interleukin 2 gene from a cosmid library by recombination in vivo
N2  - A method has been developed that allows the isolation of genomic clones from a cosmid library by homologaus recombination in vivo. This method was used to isolate a human genomic interleukin 2 (IL2) gene. The genomic cosmid library was packaged in vivo into A. phage particles. A recombination-proficient host strain carrying IL2 cDNA sequences in a non-homologaus plasmid vector was infected by the packaged cosmid library. After in vivo packaging and reinfection, recombinants carrying the antibiotic resistance genes of both vectors were selected. From a recombinant cosmid clone the chromosomal IL2 genewas restored. After DNA mediated gene transfer into mouse Ltk- cells human IL2 was expressed constitutively.
KW  - Biochemie
KW  - Recombinant DNA
KW  - DNA mediated gene transfer
KW  - expression plasmid
KW  - screening
KW  - packaging
KW  - bacteriophage lambda
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62662
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Schmidt, C. R.
A1  - Anders, A.
A1  - Barnekow, A.
T1  - Elevated expression of the cellular src gene in tumors of differing etiologies in Xiphophorus
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61889
ER  - 
TY  - JOUR
A1  - Hügle, Barbara
A1  - Scheer, Ulrich
A1  - Franke, Werner W.
T1  - Ribocharin: a nuclear M\(_r\) 40,000 protein specific to precursor particles of the large ribosomal subunit
N2  - Using a monoclonal antibody (No-194) we have identified, in Xenopus laevis and other amphibia, an acidic protein of M, 40,000 (ribocharin) which is specifically associated with the granular component of the nucleolus and nucleoplasmic 65S particles. These particles contain the nuclear 28S rRNA and apparently represent the precursor to the large ribosomal subunit in nucleocytoplasmic transit. By immunoelectron microscopy ribocharin has been localized in the granular component of the nucleolus and in interchromatin granules. During mitosis ribocharin-containing particles are associated with surfaces of chromosomes and are recollected in the reconstituting nucleoli in late telophase. We suggest that ribocharin is a specific component of precursor particles of the large ribosomal subunit, which dissociates from the 65S particle before passage through the nuclear envelope, and is reutilized in ribosome biogenesis.
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41169
ER  - 
TY  - JOUR
A1  - Hügle, Barbara
A1  - Hazan, Rachel
A1  - Scheer, Ulrich
A1  - Franke, Werner W.
T1  - Localization of ribosomal protein S1 in the granular component of the interphase nucleolus and its distribution during mitosis
N2  - Using antibodies to various nucleolar and ribosomal proteins, we define, by immunolocalization in situ, the distribution of nucleolar proteins in the different morphological nucleolar subcompartments. In the present study we describe the nucleolar localization of a specific ribosomal protein (51) by immunofluorescence and immunoelectron microscopy using a monoclonal antibody (R5 1-105). In immunoblotting experiments, this antibody reacts specifically with the largest and most acidic protein of the small ribosomal subunit (51) and shows wide interspecies cross-reactivity from amphibia to man. Beside its localization in cytoplasmic ribosomes, this protein is found to be specifically localized in the granular component of the nucleolus and in distinct granular aggregates scattered over the nucleoplasm. This indicates that ribosomal protein 51, in contrast to reports on other ribosomal proteins, is not bound to nascent pre-rRNA transcripts but attaches to preribosomes at later stages of rRNA processing and maturation. This protein is not detected in the residual nucleolar structures of cells inactive in rRNA synthesis such as amphibian and avian erythrocytes. During mitosis, the nucleolar material containing ribosomal protein 51 undergoes a remarkable transition and shows a distribution distinct from that of several other nucleolar proteins. In prophase, the nucleolus disintegrates and protein 51 appears in numerous small granules scattered throughout the prophase nucleus. During metaphase and anaphase, a considerable amount of this protein is found in association with the surfaces of all chromosomes and finely dispersed in the cell plasm. In telophase, protein 51-containing material reaccumulates in granular particles in the nucleoplasm of the newly formed nuclei and, finally, in the re-forming nucleoli. These observations indicate that the nucleolus-derived particles containing ribosomal protein 51 are different from cytoplasmic ribosomes and, in the living cell, are selectively recollected after mitosis into the newly formed nuclei and translocated into a specific nucleolar subcompartment, i.e ., the granular component. The nucleolar location of ribosomal protein 51 and its rearrangement du'ring mitosis is discussed in relation to the distribution of other nucleolar proteins.
KW  - Cytologie
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39695
ER  - 
TY  - JOUR
A1  - Dandekar, Thomas
A1  - Gramsch, Christian
A1  - Houghton, Richard A.
A1  - Schultz, Rüdiger
T1  - Affinity purification of \(\beta\)-endorphin-like material from NG108CC15 cells by means of the monoclonal \(\beta\)-endorphin antibody 3-E7
N2  - No abstract available
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29896
ER  - 
TY  - JOUR
A1  - Linsenmair, Karl Eduard
T1  - Individual and family recognition in subsocial arthropods, in particular in the desert isopod Hemilepistus reaumuri
N2  - Individual recogmtlon in the non-eusocial arthropods is, according to our present knowledge, predominantly found in the frame of permanent or temporary monogamy. In some cases, e. g. in stomatopods and possibly other marine crustaceans too, individual recognition may serve to allow identification of (i) individuals within dominance hierarchies or (ii) neighbours in territorial species thus helping to avoid the repetition of unnecessary and costly fights. Kin recognition is experimentally proven only in some isopod species (genera Hemilepistus and Porcel/io) and in the primitive cockroach (termite?) Cryptocercus. The «signatures» or «discriminators» used in the arthropods are chemical. It is assumed that the identifying substances are mainly genetically determined and in this paper I shall discuss possible evolutionary origins. The main part of this account is devoted to the presentation of some aspects of the highly developed individual and kin identification and recognition system in the desert isopod Hemilepistus reaumuri - a pure monogamous species in which pairs together with their progeny form strictly exclusive family units. Amongst other things problems of (i) mate choice, (ii) learning to recognize a partner, (iii) avoiding the un adaptive familiarization with aliens are treated. Monogamy under present conditions is for both sexes the only suitable way of maximizing reproductive success; an extremely strong selection pressure must act against every attempt to abandon monogamy under the given ecological conditions. The family «badges» which are certainly always blends of different discriminator substances are extremely variable. This variability is mainly due to genetical differences and is not environmentally caused. It is to be expected that intra-family variabiliry exists in respect of the production of discriminator substances. Since the common badge of a family is the result of exchanging and mixing individual substances, and since the chemical nature of these discriminators requires direct body contacts in order to acquire those substances which an individual does not produce itself, problems must arise with molting. These difficulties do indeed exist and they are aggravated by the fact that individuals may produce substances which do not show up in the common family badge. An efficient learning capability on the one hand and the use of inhibiting properties of newly molted isopods help to solve these problems. In the final discussion three questions are posed and - partly at least - answered; (i) why are families so strictly exclusive, (ii) how many discriminator substances have to be produced to provide a variability allowing families to remain exclusive under extreme conditions of very high population densities, (iii) what is the structure of the family badge and what does an individual have to learn apart from the badge in order not to mistake a family member for an alien or vice versa.
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33957
ER  - 
TY  - JOUR
A1  - Anders, F.
A1  - Schartl, Manfred
A1  - Barnekow, A.
A1  - Schmidt, C. R.
A1  - Luke, W.
A1  - Jaenel-Dess, G.
A1  - Anders, A.
T1  - The genes that carcinogens act upon
N2  - No abstract available.
KW  - Onkogen
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72704
ER  - 
TY  - JOUR
A1  - Barnekow, Angelika
A1  - Gessler, Manfred
T1  - Activation of the pp60\(^{c-src}\) kinase during differentiation of monomyelocytic cells in vitro
N2  - Tbe proto-oncogene c-src, the cellular homolog of the Rous sarcoma virus (RSV) transforming gene v-src, is expressed in a tissue-specific and age-dependent manner. Its physiological function, although still unknown, appears to be more closely related to differentiation processes than to proliferation processes. To obtain more information about the physiological role of the c-src gene in cells, we have studied differentiation-dependent alterations using the human HL-60 leukaemia cell line as a model system. Induction of monocytic and granulocytic differentiation of HL-60 cells by 12-0-tetradecanoylphorbol-13-acetate (TPA) and dimethylsulfoxide (DMSO) is associated with an activation of the pp60<sup>c-src</sup> tyrosine kinase, but not with increased c-src gene expression. Control experiments exclude an interaction of TPA and DMSO themselves with the pp60<sup>c-src</sup> kinase.
KW  - Biochemie
KW  - c-src
KW  - differentiation
KW  - protein tyrosine kinase
KW  - protooncogene
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59278
ER  - 
TY  - JOUR
A1  - Weich, H. A.
A1  - Sebald, Walter
A1  - Schairer, H. U.
A1  - Hoppe, J.
T1  - The human osteosarcoma cell line U-2 OS expresses a 3.8 kilobase mRNA which codes for the sequence of the PDGF-B chain
N2  - A cDNA clone of about 2500 basepairswas prepared from the human osteosarcoma cellline U-2 OS by hybridizing with a v-sis probe. Sequence analysis showed that this cDNA contains the coding region for the PDGF-B chain. Here we report that the mitogen secreted by these osteosarcoma cells contains the PDGF-B chain and is probably a homodimer of two B-chains.
KW  - Biochemie
KW  - Platelet-derived growthfactor
KW  - cDNA
KW  - Oncogene
KW  - Tumor cell
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62588
ER  - 
TY  - JOUR
A1  - Hoppe, J.
A1  - Gatti, D.
A1  - Weber, H.
A1  - Sebald, Walter
T1  - Labeling of individual amino acid residues in the membrane-embedded F\(_0\) part of the F\(_1\) F\(_0\) ATP synthase from Neurospora crassa. Influence of oligomycin and dicyclohexylcarbodiimide
N2  - Three F0 subunits and the F\(_1\) subunit P of the ATP synthase from Neurospora crassa were labeled with the lipophilic photoactivatable reagent 3-(trifluoromethyl)-3-(m-[\(^{125}\)I]iodophenyl)diazirine ([\(^{125}\)I]TID). In the proteolipid subunit which was the most heavily labeled polypeptide labeling was confmed to five residues at the NH2-terminus and five residues at the C-terminus ofthe protein. Labeling occurred at similar positions compared with the homologaus protein (subunit c) in the ATP synthase from Escherichia coli, indicating a similar structure of the proteolipid subunits in their respective organisms. The inhibitors oligomycin and dicyclohexylcarbodiimide did not change the pattern of accessible surface residues in the proteolipid, suggesting that neither inhibitor induces gross conformational changes. However, in the presence of oligomycin, the extent oflabeling in some residues was reduced. Apparently, these residues provide part of the binding site for the inhibitor. After reaction with dicyclohexylcarbodiimide an additional labeled amino acid was found at position 65 corresponding to the invariant carbodümide-binding glutamic acid. These results and previous observations indicate that the carboxyl side chain of Glu-65 is located at the protein-lipid interphase. The idea is discussed that proton translocation occurs at the interphase between different types if F\(_0\) subunits. Dicyclohexylcarbodiimide or oligomycin might disturb this essential interaction between the F\(_0\) subunits.
KW  - Biochemie
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62598
ER  - 
TY  - JOUR
A1  - Hoppe, J.
A1  - Sebald, Walter
T1  - Topological studies suggest that the pathway of the protons through F\(_0\) is provided by amino acid residues accessible from the lipid phase
N2  - The structure of the F0 part of ATP synthases from E. coli and Neurospora crassa was analyzed by hydrophobic surface labeling with [125I]TID. In the E. co/i F0 all three subunits were freely accessible to the reagent, suggesting that these subunits are independently integrated in the membrane. Labeted amino acid residues were identified by Edman degradation of the dicyclohexylcarbodiimide binding (DCCD) proteins from E. coli and Neurospora crassa. The very similar patterns obtained with the two homologaus proteins suggested the existence of tightly packed cx-helices. The oligomeric structure of the DCCD binding protein appeared to be very rigid since little, if any, change in the labeling patternwas observed upon addition of oligomycin or DCCD to membranes from Neurospora crassa. When membrancs were pretrcated with DCCD prior to the reaction with [125I]TID an additionally labeled amino acid appeared at the position of Glu·65 which binds DCCD covalently, indicating the Jocation of this inhibitor on the outside of the oligomer. It is suggested that proton conduction occurs at the surface of the oligomer of the DCCD binding protein. Possibly this oligomer rotates against the subunit a or b and thus enables proton translocation. Conserved residues in subunit a, probably located in the Iipid bilayer, might participate in the pro· ton translocation mechanism.
N2  - La structure de la partie F0 de l'ATP synthase a ete analysee au moyen de marquage par /e reactif hydrophobe TJD[125 I]. Les trois sous-unites de E. coli F0 sont accessibles au reactif ce qui semble indiquer que ces sous-unites sont integrees dans Ia membrane defaron independante. Les amino-acides marques ont ete identifies par Ia degradation d'Edman des profeines d'E. coli et de Neurospora associees au dicyclohexylcarbodiimide (DCCD). L 'analogie des courbes obtenues pour /es deux proteines homologues suggere l'existence d'a-helices rangees de faron serree. La structure oligomerique de Ia proreine associee au DCCD semble etre tres rigide puisque pratiquement aucun changement dans /e marquage n 'a ete observe par addition d'oligomycine ou de DCCD aux membranes de Neurospora crassa. Quand /es membranes sont traitees avec /e DCCD avant Ia reaction avec TJD[125 I], un amino-acide additionnellement marque apparait a Ia position Glu·65 et forme avec le DCCD une Iiaison covalente. Ce dernier resu/tat indique Ia localisation de cet inhibiteur a /'exterieur de J'oligo· mere. II semble donc que Ia conduction des protons ait lieu a Ia surface de /'oligomere de Ia proteine associee au DCCD. II serait possib/e que l'o/igomere se retourne contre Ia sous-unite a ou b, permettunt de ce fait Ia translocation des protons. Les residus conserves de Ia sous-unite a, probab/ement Jocalises dans Ia double couche lipidique, pourraient participer au mecanisme de translocation des protons.
KW  - Biochemie
KW  - conduction de protons
KW  - proteines membranaires
KW  - carbenes
KW  - proton conduction
KW  - membrane proteins
KW  - carbenes
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62602
ER  - 
TY  - JOUR
A1  - Gabellini, N.
A1  - Sebald, Walter
T1  - Nucleotide sequence and transcription of the fbc operon from Rhodopseudomonas sphaeroides. Evaluation of the deduced amino acid sequences of the FeS protein, cytochrome b and cytochrome c\(_1\)
N2  - No abstract available
KW  - Biochemie
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62615
ER  - 
TY  - JOUR
A1  - McCarthy, J. E.
A1  - Sebald, Walter
A1  - Gross, G.
A1  - Lammers, R.
T1  - Enhancement of translational efficiency by the Escherichia coli atpE translational initiation region: its fusion with two human genes
N2  - No abstract available
KW  - Biochemie
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62626
ER  - 
TY  - JOUR
A1  - Kobelt, Frank
A1  - Linsenmair, Karl Eduard
T1  - Adaptations of the reed frog Hyperolius viridiflavus to its arid environment. I. The skin of Hyperolius viridiflavus nitidulus in wet and dry season conditions.
N2  - Hyperolius viridiflavus nitidulus inhabits parts of the seasonally very hot and dry West African savanna. During the long lasting dry season, the small frog is sitting unhidden on mostly dry plants and has to deal with high solar radiation load (SRL), evaporative water loss (EWL) and small energy reserves. It seems to be very badly equipped to survive such harsh climatic conditions (unfavorable surface to volume ratio, very limited capacity to störe energy and water). Therefore, it must have developed extraordinary efficient mechanisms to solve the mentioned Problems. Some of these mechanisms are to be looked for within the skin of the animal (e.g. protection against fast desiccation, deleterious effects of UV radiation and over-heating). The morphology of the wet season skin is, in most aspects, that of a "normal" anuran skin. It differs in the Organization of the processes of the melanophores and in the arrangement of the chromatophores in the Stratum spongiosum, forming no "Dermal Chromatophore Unit". During the adaptation to dry season conditions the number of iridophores in dorsal and ventral skin is increased 4-6 times compared to wet season skin. This increase is accompanied by a very conspicuous change of the wet season color pattern. Now, at air temperatures below 35° C the color becomes brownish white or grey and changes to a brilliant white at air temperatures near and over 40° C. Thus, in dry season State the frog retains its ability for rapid color change. In wet season State the platelets of the iridophores are irregularly distributed. In dry season State many platelets become arranged almost parallel to the surface. These purine crystals probably act as quarter-wave-length interference reflectors, reducing SRL by reflecting a considerable amount of the radiated energy input. EWL is as low as that of much larger xeric reptilians. The impermeability of the skin seems to be the result of several mechanisms (ground substance, iridophores, lipids, mucus) supplementing each other. The light red skin at the pelvic region and inner sides of the limbs is specialized for rapid uptake of water allowing the frog to replenish the unavoidable EWL by using single drops of dew or rain, available for only very short periods.
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-30551
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Hansmann, Paul
A1  - Falk, Heinz
A1  - Sitte, Peter
T1  - Ultrastructural localization of DNA in two Cryptomonas species by use of a monoclonal DNA-antibody
N2  - Immunogold cytochemistry - DNA localization - Cryptomonas nucleomorph The distribution and subcellular localization of DNA in the unicellular alga Cryptomonas has been investigated electron-microscopically by indirect immunocytochemistry, using a monoclonal DNA antibody and a gold-Iabeled secondary antibody. This technique proved to be very sensitive and entirely specific. DNA could be demonstrated in four different compartments (nucleus, nucleomorph, plastid, and mitochondrion). Within the plastid, DNA is concentrated in stroma regions that are localized preferentially around the center of the organelle. The mitochondrion contains several isolated DNA-containing regions (nucleoids). Within the nucleus, most of the DNA is localized in the 'condensed' chromatin. DNA was also detectable in small areas of the nucleolus, whereas the interchromatin space of the nucleus appeared almost devoid of DNA. Within the nucleomorph, DNA is distributed inhomogeneously in the matrix. DNA could furthermore be detected in restricted areas of the 'fibrillogranular body' of the nucleomorph, resembling the situation encountered in the nucleol us. The presence of DNA and its characteristic distribution in the nucleomorph provide additional, strong evidence in favour of the interpretation of that organelle as the residual nucleus of a eukaryotic endosymbiont in Cryptomonas.
KW  - Cytologie
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39746
ER  - 
TY  - JOUR
A1  - Dandekar, Thomas
T1  - Offenlegungsschrift (über einen Biosensor)
N2  - No abstract available
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31683
ER  - 
TY  - JOUR
A1  - Schultz, Rüdiger
A1  - Metzner, Katharina
A1  - Dandekar, Thomas
A1  - Gramsch, Christian
T1  - Opiates induce long-term increases in prodynorphin derived peptide levels in the guinea-pig myenteric plexus
N2  - No abstract available
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29809
ER  - 
TY  - JOUR
A1  - Hadjiolova, Krassimira
A1  - Rose, Kathleen M.
A1  - Scheer, Ulrich
T1  - Immunolocalization of nucleolar proteins after D-galactosamine-induced inhibition of transcription in rat hepatocytes
N2  - No abstract available
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33205
ER  - 
TY  - JOUR
A1  - Reimer, Georg
A1  - Scheer, Ulrich
A1  - Peters, Jan-Michael
A1  - Tan, Eng M.
T1  - Immunolocalization and partial characterization of a nucleolar autoantigen (PM-Scl) associated with polymyositis / scleroderma overlap syndromes.
N2  - Precipitating anti-PM-Sel antibodies are present in sera from patients with polymyositis. scleroderma. and polymyositis/scleroderma overlap syndromes. By indirect immunofluorescence microscopy. anti-PM-Scl antibodies stained the nucleolus in cells of different tissues and species. suggesting that the antigen is highly conserved. By electron microscopy, anti-PM-Scl antibodies reacted primarily with the granular component of the nuc1eolus. Drugs that inhibit rRNA synthesis had a marked effect on the expression of PM-Scl antigen. In actinomycin D-treated cells, immunofluorescence staining by anti-PM-Scl was signüicantly reduced with residual staining restricted to the granular regions of nuc1eoli. Treatment with 5,6-dichloro-beta-D- ribofuranosylbenzimidazole (DRB) also selectively reduced nuc1eolar staining. On a molecular level, anti-PM-Sel antibodies precipitated 11 polypeptides with molecular weights (Mr) ranging from 110,000 to 20,000. The Mr 80,000 and 20.000 polypeptides were phosphorylated. Evidence suggests that the PM-Scl antigen complex may be related to a prerlbosomal particle.
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33191
ER  - 
TY  - JOUR
A1  - Linsenmair, Karl Eduard
T1  - Adaptations of the reed frog Hyperbolius viridiflavus to its arid environment: II. Some aspects of the water economy of H. viridiflavus nitidulus under wet and dry ...
N2  - Adaptations to aridity ofthe reedfrog Hyperolius viridiflavus nitidulus, living in different parts of the seasonally very dry and hot West African savanna, are investigated ...
KW  - Zoologie
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78395
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - Das Chromatin : seine Struktur und Funktion
N2  - no abstract available
KW  - Chromatin
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-80790
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - Injection of antibodies into the nucleus of amphibian oocytes: an experimental means of interfering with gene expression in the living cell
N2  - No abstract available
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41182
ER  - 
TY  - JOUR
A1  - Zimmermann, U.
A1  - Stopper, Helga
T1  - Elektrofusion und Elektropermeabilisierung von Zellen
N2  - No abstract available.
KW  - Elektrofusion
KW  - Elektroporation
KW  - Zelle
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86865
ER  - 
TY  - JOUR
A1  - Mahsberg, Dieter
T1  - Contact chemoreception of prey in hunting scorpions
N2  - Scorpions commonly are assumed to hunt on living prey. But under laboratory conditions they also respond very sensitively to dead insects lying on the substrate. In many cases the motionless prey is seized and consumed. It was investigated how this behavior can be elicited. The buthid scorpions Androctonus australis (L.) and Buthus occitanus (Am.) not only find motionless prey again which was stung but managed to escape before dying: They also respond to extracts of the cuticle of prey insects. After touching prey marks' either with the tips of the chelae fingers or the tarsi of the walking legs or the pectine organs specific responses (searching, seizing, feeding) are released at a high rate. Behavioral experiments demonstrate for the first time the chemosensitivity of the pectine organs for which only mechanosensitivity had been proofed formerly. Mechanical as well as contact chemical stimulation of these organs cause scorpions to orient towards the stimulus source which is grasped, retained and consumed or rejected depending on its quality. The probably responsible chemosensitive receptors are already described in the literature. The possible adaptive value and the biological significance of contact chemoreception in prey catching and in other aspects of the life of scorpions is discussed.
KW  - Skorpion
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-45784
ER  - 
TY  - JOUR
A1  - Maueler, W.
A1  - Eigenbrodt, E.
A1  - Schartl, Manfred
T1  - Intermediary metabolism of normal and tumorous tissue of Xiphophorus (Teleostei: Poeciliidae)
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61855
ER  - 
TY  - JOUR
A1  - Barnekow, A.
A1  - Schartl, Manfred
T1  - Comparative studies on the src proto-oncogene and its gene product pp60\(^{c-src}\) in normal and neoplastic tissues of lower vertebrates
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61869
ER  - 
TY  - JOUR
A1  - Kleene, R.
A1  - Pfanner, N.
A1  - Pfaller, R.
A1  - Link, T. A.
A1  - Sebald, Walter
A1  - Neupert, W.
A1  - Tropschug, M.
T1  - Mitochondrial porin of Neurospora crassa: cDNA cloning, in vitro expression and import into mitochondria
N2  - No abstract available
KW  - Biochemie
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62566
ER  - 
TY  - JOUR
A1  - Römisch, J.
A1  - Tropschug, M.
A1  - Sebald, Walter
A1  - Weiss, H.
T1  - The primary structure of cytochrome c\(_1\) from Neurospora crassa
N2  - No abstract available
KW  - Biochemie
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62578
ER  - 
TY  - JOUR
A1  - Barnekow, A.
A1  - Paul, E.
A1  - Schartl, Manfred
T1  - Expression of the c-src protooncogene in human skin tumors
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61870
ER  - 
TY  - JOUR
A1  - Benavente, Ricardo
A1  - Rose, Kathleen M.
A1  - Reimer, Georg
A1  - Hügle-Dörr, Barbara
A1  - Scheer, Ulrich
T1  - Inhibition of nucleolar reformation after microinjection of antibodies to RNA polymerase I into mitotic cells
N2  - The formation of daughter nuclei and the reformation of nucleolar structures was studied after microinjection of antibodies to RNA polymerase I into dividing cultured cells (PtK2). The fate of several nucleolar proteins representing the three main structural subcomponents of the nucleolus was examined by immunofluorescence and electron microscopy. The results show that the RNA polymerase I antibodies do not interfere with normal mitotic progression or the early steps of nucleologenesis, i.e. , the aggregation of nucleolar material into prenucleolar bodies. However,they inhibit the telophasic coalescence of the prenucleolar bodies into the chromosomal nucleolar organizer regions, thus preventing the formation of new nucleoli. These prenucleolar bodies show a fibrillar organization that also compositionally resembles the dense fibrillar component of interphase nucleoli . We conclude that during normal nucleologenesis the dense fibrillar component forms from preformed entities around nucleolar organizer regions, and that this association seems to be dependent on the presence of an active form of RNA polymerase I.
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-33247
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Raska, I.
T1  - Immunocytochemical localization of RNA polymerase I in the fibrillar centers of nucleoli
N2  - No abstract available
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39618
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
T1  - Structure of lampbrush chromosome loops during different states of transcriptional activity as visualized in the presence of physiological salt concentrations
N2  - Lampbrush chromosomes of amphibian oocytes were isolated in the presence of near-physiological salt concentrations, to preserve their native state, and studied by electron microscopy of ultrathin s~dions. The transcriptional state of the lampbrush chromosomes was experimentally modulated by incubating the oocytes for various time periods in medium containing actinomycin D. The observations show that the structure of the lateral loops changes rapidly in response to alterations in transcriptional activity. During decreasing transcriptional activity and reduced packing density of transcripts, the chromatin axis first condensed into nucleosomes and then into an approximately 30 nm thick higher order chromatin fiber. Packaging of the loop axis into supranucleosomal structures may contribute to the foreshortening and retraction of the loops observed during inhibition of transcription and in later stages of meiotic prophase. The increasing packing density of the DNA during the retraction process of the loops could also be visualized by immunofluorescence microscopy using antibodies to DNA. The dependence of the loop chromatin structure on transcriptional activity is discussed in relation to current views of mechanisms involved in gene activation.
KW  - lampbrush chromosomes
KW  - chromatin structure
KW  - electron microscopy
KW  - immunofluorescence microscopy
KW  - DNA antibodies
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-39304
ER  - 
TY  - JOUR
A1  - Dandekar, Thomas
A1  - Schulz, R.
T1  - Evidence for the expression of peptides derived from three opioid precursors in NG 108CC15 hybrid cells
N2  - No abstract available
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-29909
ER  - 
TY  - JOUR
A1  - Maschwitz, U.
A1  - Fiala, Brigitte
A1  - Dolling, W. R.
T1  - New trophobiotic symbioses of ants with South East Asian bugs
N2  - A trophobiotic relationship between two species of phloem-feeding plataspid bugs and an ant, Meranoplus mucronatus, was discovered on tree trunks in Malaysia. Similar relationships were found between coreid bugs and Crematogaster sp. and Anoplolepis longipes, on bamboo in the same area. The ants recruit to groups of the bugs and feed on the liquid, sugar-rich faeces of the larvae, stimulating release of the honeydew by tactile signals. They protect all stages of the bugs from disturbance by biting and by the use of defensive secretions. Phloem-feeding bugs in the families Plataspidae and Coreidae need long sty lets to pierce the thick bark of their host tree. The different methods of accommodating the resting stylets in these two families are described. The plataspids are described as Tropidotylus servus sp. novo and T. minister sp. novo A coreid previously reported in association with M. mucronatus in Malaya is described as Hygia cliens sp. novo The coreids on bamboo were determined as Cloresmus spp. and Notobitus affinis.
KW  - Ants
KW  - Coreidae
KW  - Heteroptera
KW  - Malaya
KW  - New Species
KW  - Plataspidae
KW  - Trophobiosis
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34030
ER  - 
TY  - JOUR
A1  - Reimer, Georg
A1  - Rose, Kathleen M.
A1  - Scheer, Ulrich
A1  - Tan, Eng M.
T1  - Autoantibody to RNA polymerase I in scleroderma sera
N2  - Autoantibodies to components of the nucleolus are a unique serological feature of patients with scleroderma. There are autoantibodies of several specificities; one type produces a speckled pattern of nucleolar staining in immunofluorescence. In actinomycin D and 5,6-dichloro-{j-D-ribofuranosylbenzimidazoletreated Vero cells, staining was restricted to the fibrillar and not the granular regions. By double immunofluorescence, specific rabbit anti-RNA polymerase I antibodies stained the same fibrillar structures in drug-segregated nucleoli as scleroderma sera. Scleroderma sera immunoprecipitated 13 polypeptides from (35S)methionine-labeled HeLa cell extract with molecular weights ranging from 210,000 to 14,000. Similar polypeptides were precipitated by rabbit anti-RNA polymerase I antibodies, and their common identities were confirmed in immunoabsorption experiments. Microinjection of purified IgG from a patient with speckled nucleolar staining effectively inhibited ribosomal RNA transcription. Autoantibodies to RNA polymerase I were restricted to certain patients with scleroderma and were not found in other autoimmune diseases.
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34294
ER  - 
TY  - JOUR
A1  - Scheer, Ulrich
A1  - Messner, Karin
A1  - Hazan, Rachel
A1  - Raska, Ivan
A1  - Hansmann, Paul
A1  - Falk, Heinz
A1  - Spiess, Eberhard
A1  - Franke, Werner W.
T1  - High sensitivity immunolocalization of double and single-stranded DNA by a monoclonal antibody
N2  - A monoclonal antibody (AK 30-10) is described which specifically reacts with DNA both in double and single-stranded forms but not with other molecules and structures, including deoxyribonucleotides and RNAs. When used in immunocytochemical experiments on tissue sections and permeabilized cultured cells, this antibody detects DNA-containing structures, even when the DNA is present in very small amounts. Examples of high resolution detection include the DNA present in amplified extrachromosomal nucleoli, chromomeres of lampbrush chromosomes, mitochondria, chloroplasts and mycoplasmal particles. In immunoelectron microscopy using the immunogold technique, the DNA was localized in distinct substructures such as the "fibrillar centers" of nucleoli and certain stromal centers in chloroplasts. The antibody also reacts with DNA of chromatin of living cells, as shown by microinjection into cultured mitotic cells and into nuclei of amphibian oocytes. The potential value and the limitations of immunocytochemical DNA detection are discussed.
KW  - Cytologie
KW  - DNA antibodies
KW  - monoclonal antibodies
KW  - DNA immunolocalization
KW  - chromatin
KW  - mycoplasma tests
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41063
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Schröder, Johannes Horst
T1  - A new species of the genus Xiphophorus Heckel 1848, endemic to northern Coahuila, Mexico (Pisces: Poeciliidae)
N2  - Xiphophorus meyeri n. sp. is described as an endemic to Muzquiz, Coahuila, Mexico. It appears to be the northernmost species of the genus. The new species is related to X. couchianus and X. gordoni, but differs morphologically from those by dorsal fin ray number, by the expression of some gonopodial features and most markedly by the appearance of macromelanophores or tr-melanophores.
KW  - Schwertkräpfling
KW  - Coahuila
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87117
ER  - 
TY  - JOUR
A1  - Peschke, Klaus
A1  - Mahsberg [geb. Krapf], Dieter
A1  - Fuldner, Dietrich
T1  - Ecological separation, functional relationships, and limiting resources in a carrion insect community
N2  - 1. Thr ecological separation of 19 carrion inscet species (adults and some of their larvae) was investigated at rabbit carcasses in North Bavaria (FRG) referring to 4 niche dimensions. In the (1.) macrohabitats (forest - clearing) the distribution of saprophageous beetle larvae was mainly considered, for (2.) seasonality the differential abundance of blow flies (Colliphoridae). (3.) The stages of decay were correlated with the temperature dependent development of blow fly maggots affecting the abundance of competing saprophageous beetles and of carnivors preying upon maggots of different size classes. By using ( 4.) microhabitats (spatial subdivision of a carcass) as further niche dimension, the dustering of speries using similar food resources was domonstrated in a niche overlap dendrogram.
2. The quantitative effect of predators on blow fly maggots was investigated both in field and laboratory experiments. Predation upon maggots rcduces their scramble competition, resulting in a higher pupal weight. Thus, the reproductive succcss of the blow flies seems to be buffered by the developmental flexibility of the calliphorids. The numerical effect of predators and parasitoids on the blow fly pupae was also quantified.
3. In a case study on the staphylinid beetle, Aleochara curtula, we investigated the diffenntial abundance of sexes. The ratio at which the males and females arrive at the carcass is balanced. Here the beetles feed and copulated. Females depart into the vicinity of the carrion much earlier than males, thus shifting the sex ratio to a maale bias. In the surroundings the females deposit their eggs, and the parasitoid first instar larvae search for scattered blow fly pupae. The temporal and spatial distribution of both sexes of A. curtula is thus not only affected by the food allocation of the adults, but a.lso by limiting resources of mating end egg laying sites as well as larval hosts.
KW  - Aaskäfer
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86361
ER  - 
TY  - JOUR
A1  - Foerster, Wolfgang
A1  - Schartl, Manfred
T1  - Karyotype and isozyme patterns of five species of Aulonocara REGAN, 1922
N2  - No abstract available.
KW  - Aulonocara
KW  - Karyotyp
KW  - Isoenzym
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86774
ER  - 
TY  - JOUR
A1  - Adam, D.
A1  - Wittbrodt, J.
A1  - Telling, A.
A1  - Schartl, Manfred
T1  - RFLP for an EGF-receptor related gene associated with the melanoma oncogene locus of Xiphophorus maculatus
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61822
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Peter, R. U.
T1  - Progressive growth of fish tumors after transplantation into thymus-aplastic (nu/nu) mice
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61833
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
T1  - A sex chromosomal restriction-fragment-length marker linked to melanoma-determining Tu loci in Xiphophorus
N2  - No abstract available
KW  - Physiologische Chemie
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61842
ER  - 
TY  - JOUR
A1  - Gessler, Manfred
A1  - Bruns, Gail A. P.
T1  - Molecular mapping and cloning of the breakpoints of a chromosome 11p14.1-p13 deletion associated with the AGR syndrome
N2  - Chromosome 11p13 is frequently rearranged in individuals with the WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and mental retardation) or parts of this syndrome. To map the cytogenetic aberrations molecularly, we screened DNA from cell Unes with known WAGR-related chromosome abnormalities for rearrangements with pulsed fleld gel (PFG) analysis using probes deleted from one chromosome 11 homolog of a WAGR patient. The first alteration was detected in a cell line from an individual with aniridia, genitourinary anomalies, mental retardation, and a deletion described as 11p14.1-p13. We have located one breakpoint close to probe HU11-164B and we have cloned both breakpoint sites as well as the junctional fragment. The breakpoints subdivide current intervals on the genetic map, and the probes for both sides will serve as important additional markers for a long-range restriction map of this region. Further characterization and sequencing of the breakpoints may yield insight into the mechanisms by which these deletions occur.
KW  - Biochemie
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59264
ER  - 
TY  - JOUR
A1  - Goebel, Werner
A1  - Chakraborty, T.
A1  - Kreft, Jürgen
T1  - Bacterial hemolysins as virulence factors
N2  - No abstract available
KW  - Biologie
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60553
ER  - 
TY  - JOUR
A1  - Goebel, Werner
A1  - Kathariou, S.
A1  - Kuhn, M.
A1  - Sokolovic, Z.
A1  - Kreft, Jürgen
A1  - Köhler, S.
A1  - Funke, D.
A1  - Chakraborty, T.
A1  - Leimeister-Wächter, M.
T1  - Hemolysin from Listeria-biochemistry, genetics and function in pathogenesis
N2  - No abstract available
KW  - Biologie
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60563
ER  - 
TY  - JOUR
A1  - Thiry, Marc
A1  - Scheer, Ulrich
A1  - Goessens, Guy
T1  - Immunoelectron microscopic study of nucleolar DNA during mitosis in Ehrlich tumour cells
N2  - In order to investigate the DNA localization within Ehrlich tumor cell nucleoli during mitosis, two recent immunocytochemical methods using either an anti-DNA or an anti-bromodeoxyuridine (BrdU) monoclonal antibody have been applied. In both cases, the immunogold labeling has been performed on ultrathin sections of cells embedded either in Lowicryl K4M or in Epon, respectively. Identical results are observed with both immunocytochemical approaches. In the interphase nucleolus, besides the labeling of the perinucleolar chromatin shell and of its intranucleolar invaginations which penetrate into the nucleolar body and often terminate at the fibrillar centers, a few gold particles are also preferentially found towards the peripheral region of the fibrillar centers. In contrast, the dense fibrillar component and the granular component are never labeled. During mitosis, the fibrillar centers persist at the chromosomal nucleolus organizing regions (NOR's) and can be selectively stained by the silver method. However, these metaphase fibrillar centers are no longer decorated by the DNA- or BrdU antibodies. These results indicate that until the end of prophase, rRNA genes are present inside the fibrillar center material, disappear during metaphase and reappear in reconstituting nucleoli during telophase. Thus, fibrillar centers appear to represent structures sui generis, which are populated by rRNA genes only when the nucleolus is functionally active. In segregated nucleoli after actinomycin D treatment, the DNA labeling is exclusively restricted to the perinucleolar chromatin blocks. These findings also suggest that the DNA content of the fibrillar center material varies according to the rRNA transcription level of the cells. The results are discussed in the light of the present knowledge of the functional organization of the nucleolus.
KW  - Cytologie
KW  - Nucleolus
KW  - DNA
KW  - mitosis
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-40745
ER  - 
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  -