@article{SchluppParzefallEpplenetal.1992,
  author    = {Schlupp, Ingo and Parzefall, Jakob and Epplen, J{\"o}rg T. and Nanda, Indrajit and Schmid, Michael and Schartl, Manfred},
  title     = {Pseudomale behaviour and spontaneous masculinization in the all-female teleost Poecilia formosa (Teleostei: Poeciliidae)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61688},
  year      = {1992},
  abstract  = {Pseudosexual behaviour is a rare phenomenon associated with unisexuality in vertebrates. In the gynogenetic, all-female teleost Poecilia formosa, rare individuals occur that resemble males of closely related gonochoristic species both in behaviour and external morphology. These masculinized gynogens and normal gynogens are members of the same clone, as demonstrated by DNA-fingerprinting. The behaviour of these masculinized gynogens is described and compared to the behaviour of the gonochoristic species Poecilia mexicana, P. latipinna and their hybrid as weil as androgen-treated individuals of P. formosa. No statistically significant difTerences were found between masculinized gynogens and hormonetreated individuals nor between the gonochoristic P. mexicana and P. latipinna males. Differences exist between gonochoristic and unisexual species. Passihle causes and effects of masculinized gynogens are discussed.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchliewenFrickeSchartletal.1993,
  author    = {Schliewen, U. and Fricke, H. and Schartl, Manfred and Epplen, J{\"o}rg T. and Paabo, S.},
  title     = {Which home for coelacanth?},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61606},
  year      = {1993},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlSchmidtAndersetal.1985,
  author    = {Schartl, Manfred and Schmidt, C. R. and Anders, A. and Barnekow, A.},
  title     = {Elevated expression of the cellular src gene in tumors of differing etiologies in Xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61889},
  year      = {1985},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlSchluppSchartletal.1991,
  author    = {Schartl, Manfred and Schlupp, Ingo and Schartl, Angelika and Meyer, Manfred K. and Nanda, Indrajit and Schmid, Michael and Epplen, J{\"o}rg T. and Parzefall, Jakob},
  title     = {On the stability of dispensable constituents of the eukaryotic genome: Stability of coding sequences versus truly hypervariable sequences in a clonal vertebrate, the amazon molly, Poecilia formosa},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61731},
  year      = {1991},
  abstract  = {In dooal unisexual vertebrales, the genes specifying the males become dispensable. To study tbe rate of such geoes the gynogeoetic all-female fisb Poecilillfonnolll was treated with androgens. Phenotypic males were obtained that exbibited the complete set of male cbaracteristics of dosely related gooocboristic species, induding body proportions, pigmentation, the extremely complex insemination apparatus of poecil{\"u}d fish, sexual bebavior, and spermatogeoesls. Tbe apparent stabllity of such genic structures, induding those involved in androgen regulation, is contrasted by high instability of noncoding sequeaces. Frequent mutations, thelr donal transmission, and at least two truly hypervariable Iod leading to individual difl'ereaces between these othenrise donal organisms were detected by DNA fingerprinting. These observations substantiate the concept that also in "ameiotic" vertebrates certain compartments of the genome are more prooe to mutatiooal alterations than others.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlPeter1988,
  author    = {Schartl, Manfred and Peter, R. U.},
  title     = {Progressive growth of fish tumors after transplantation into thymus-aplastic (nu/nu) mice},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61833},
  year      = {1988},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlErbeldingDenkHolteretal.1993,
  author    = {Schartl, Manfred and Erbelding-Denk, Claudia and Holter, Sabine and Nanda, Indrajit and Schmid, Michael and Schroder, Johannes H. and Epplen, J{\"o}rg T.},
  title     = {Reproductive failure of dominant males in the poeciliid fish Limia perugiae determined by DNA fingerprinting},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61643},
  year      = {1993},
  abstract  = {Hierarchical structures among male indlviduals in a population are frequently reflected ln differences in aggressive and reproductive behavior and access to the females. In general, sodal dominance requires the Investments, which in turn then may have to be compensated for by high reproductive success. However, this hypothesls has so far only been sufficiently tested in small mating groups (one or two males with one or two females) due to the difficulties of determining paternity by conventional methods. DNA fingerprinting overcomes these problems by offering the possibility to determine genetic relationships and mating patterns within larger groups [Borke, T. (1989) Trends Ecol. Evol. 4, 139-144]. We show here that in the poecUiid fish Limia perugitu, in small matlng groups the dominant male has 8 mating success of 100\%, whereas ln larger groups lts contribution to the offspring unexpectedly drops to zero.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlBarnekowBaueretal.1982,
  author    = {Schartl, Manfred and Barnekow, A. and Bauer, H. and Anders, F.},
  title     = {Correlations of inheritance and expression between a tumor gene and the cellular homolog of the Rous sarcoma virus-transforming gene in Xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61937},
  year      = {1982},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlBarnekow1984,
  author    = {Schartl, Manfred and Barnekow, A.},
  title     = {Differential expression of the cellular src gene during vertebrate development},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61893},
  year      = {1984},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlBarnekow1984,
  author    = {Schartl, Manfred and Barnekow, A.},
  title     = {Cellular src gene product detected in the freshwater sponge Spongilla lacustris},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61904},
  year      = {1984},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlAdam1992,
  author    = {Schartl, Manfred and Adam, Dieter},
  title     = {Molecular cloning, structural characterization, and analysis of transcription of the melanoma oncogene of xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61989},
  year      = {1992},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{Schartl1988,
  author    = {Schartl, Manfred},
  title     = {A sex chromosomal restriction-fragment-length marker linked to melanoma-determining Tu loci in Xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61842},
  year      = {1988},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{Schartl1990,
  author    = {Schartl, Manfred},
  title     = {Homology of melanoma-inducing loci in the genus Xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61757},
  year      = {1990},
  abstract  = {Several species of the genus Xiphophorus are polymorphic for specific pigment patterns. Same of these give rise to malignant melanoma following the appropriate crossings. For one of these pattern Iod from the platyfish Xiphophorus maculatus the melanoma-inducing gene has been doned and found to encode a novel receptor tyrosine kinase, designated Xmrk. Using molecular probes from this gene in Southern blot analyses on single fish DNA preparations from 600 specimens of different populations of various species of the genus Xiphophorus and their hybrids, either with or without melanomapredisposing pattern, it was shown that all individuals contain the Xmrk gene as a proto-oncogene. It is located on the sex chromosome. All fish that carry a melanoma-predisposing locus which has been identified by Mendelian genetics contain an additional copy of Xmrk, closely linked to a specific melanophore pattern locus on the sex chromosome. The melanoma-inducing loci of the different species and populations are homologous. The additional copy of Xmrk obviously arose by a geneduplication event, thereby acquiring the oncogenic potential. The homology of the melanomainducing Iod points to a similar mechanism of tumor suppression in all feral fish populations of the different species of the genus Xiphophorus.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{SchartlDimitrijevicSchartl1994,
  author    = {Schartl, A. and Dimitrijevic, N. and Schartl, Manfred},
  title     = {Evolutionary origin and molecular biology of the melanoma-inducing oncogene of Xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61954},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{RiehlSchartlKollinger1984,
  author    = {Riehl, R. and Schartl, Manfred and Kollinger, G.},
  title     = {Comparative studies on the ultrastructure of malignant melanoma in fish and human by freeze-etching and transmission electron microscopy},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61920},
  year      = {1984},
  abstract  = {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.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{RiehlSchartl1984,
  author    = {Riehl, R. and Schartl, Manfred},
  title     = {A Transmission Electron Microscopical and Freeze-Etch Study of Malignant-Melanoma in Fish},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61916},
  year      = {1984},
  abstract  = {No abstract available},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{RaulfRobertsonSchartl1989,
  author    = {Raulf, F. and Robertson, S. M. and Schartl, Manfred},
  title     = {Evolution of the neuron-specific alternative splicing product of the c-src proto-oncogene},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61796},
  year      = {1989},
  abstract  = {The observation of a slower migrating form of pp6oc-src in neural tissue of chicken and mouse has recently been shown to be due to an alternative transcript form of tbe c-src gene (Martinez et al.: Science 237:411-415, 1987; Levy et al.: Mol Cell Bio17:4142- 4145, 1987). An insertion of 18 basepairs between exons 3 and 4, presumed to be due to alternative splicing of a mini-exon, gives rise to six amino acid residues not found in the non-neuronal (termed flbroblastic) form of pp60\(^{c-src}\). Wehave addressed the question of the evolutionary origin of the c-src neuronal insert · and its functional signiflcance regarding neural-speciflc expression of the c-src gene. To this end we have investigated whether the c-src gene of a lower verlebrate (the teleost fish Xiphophorus) gives rise to a neural-specific transcript in an analogous manner. We could show that the fish c-src gene does encode for a "fibroblastic" and a "neuronal" form of transcript and that the neuronal transcript does indeed arise by way of alternative splicing of a mini-exon. The miniexon is also 18 basepairs long and we could demoostrate directly that this exon lies within the intron separating exons 3 and 4. For comparative purposes we have examined whether the fish c-yes gene, the member of the src gene family most closely related to c-src, also encodes a neural tissue-specific transcript. No evidence for a second transcript form in brain was obtained. This result suggests that the mini-exon arose within the c-src gene lineage sometime between the srclyes gene duplication event and the divergence of the evolutionary lineage giving rise to the teleost fish. Published genomic sequence of src-related genes in Drosophila and our own results with Hydra demoostrate no intron in these species at the analogous location, consistent with first appearance of this mini-exon sometime between 550 and 400 million years ago.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{NandaSchartlFeichtingeretal.1992,
  author    = {Nanda, Indrajit and Schartl, Manfred and Feichtinger, Wolfgang and Epplen, J{\"o}rg T. and Schmid, Michael},
  title     = {Early stages of sex chromosome differentiation in fish as analysed by simple repetitive DNA sequences},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61715},
  year      = {1992},
  abstract  = {Animal sex chromosome evolution has started on different occasions with a homologous pair of autosomes leading to morphologically differentiated gonosomes. In contrast to other vertebrate classes, among fishes cytologically dernonstrahle sex chromosomes are rare. In reptiles, certain motifs of simple tandemly repeated DNA sequences like (gata)\(_n\)/(gaca)\(_m\) are associated with the constitutive heterochromatin of sex chromosomes. In this study a panel of simple repetitive sequence probes was hybridized to restriction enzyme digested genomic DNA of poeciliid fishes. Apparent male heterogamety previously established by genetic experiments in Poecilia reticulata (guppy) was correlated with male-specific hybridization using the (GACA)\(_4\) probe. The (GATA)\(_4\) oligonucleotide identifies certain male guppies by a Y chromosomal polymorphism in the outbred population. In cantrast none of the genetically defined heterogametic situations in Xiphophorus could be verified consistently using the collection of simple repetitive sequence probes. Only individuals from particular populations produced sex-specific patterns of hybridization with (GATA)\(_4\). Additional poeciliid species (P. sphenops, P. velifera) harbour different sex-specifically organized simple repeat motifs. The observed sex-specific hybridization patterns were substantiated by banding analyses of the karyotypes and by in situ hybridization using the (GACA)\(_4\) probe.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{NandaSchartlEpplenetal.1993,
  author    = {Nanda, Indrajit and Schartl, Manfred and Epplen, J{\"o}rg T. and Feichtinger, Wolfgang and Schmid, Michael},
  title     = {Primitive sex chromosomes in poeciliid fishes harbor simple repetitive DNA sequences},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61659},
  year      = {1993},
  abstract  = {The demonstration ofthe chromosomal mode ofsex determinationvia genetic experiments as well as the absence of heteromorphic sex chromosomes affirm poeciliid fishes as a unique group among vertebrates that are endowed with the mostprimitive form of sex chromosornes. In many different taxa the evolutionary process involved in the differentiation ofadvanced sex chromosomes is outlined through sex specifically organized repetitive sequences. In this investigation hydridization of synthetic probes specific to genomic simple repeat motifs uncovers a sex-specific hybridization pattern in certain viviparaus fishes ofthe family Poeciliidae. The hybridization pattern together with specific staining ofthe constitutive heterochromatin by C-banding reveals heterogamety in males (Poecilia reticulata) as weil as in females (P. sphenops). In P. velifera, however, C-banding alone fails to unravel the heterogametic status. The female specific W-chromosome can be detected by simple repetitive sequence probes. Therefore, the principal significance of heterochromatization as a means of generating differentiated sex chromosomes is evident.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{NakayamaForestiTewarietal.1994,
  author    = {Nakayama, Ichiro and Foresti, Fausto and Tewari, Rita and Schartl, Manfred and Chourrout, Daniel},
  title     = {Sex chromosome polymorphism and heterogametic males revealed by two cloned DNA probes in the ZW/ZZ fish Leporinus elongatus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61583},
  year      = {1994},
  abstract  = {In order to study the divergence of teleost sex chromosomes, subtractive cloning was carried out between genomic DNA ofmales and females ofthe rainbow trout (XX/XY) and of Leporinus elongatus (ZW /ZZ). Inserts cloned in a plasmid vector were individually tested on Southern blots of DNA of males and females for sex specificity. No sex-specific insert was obtained from trout, but two out of ten inserts cloned from L. elongatus showed sex-specific patterns in this species: one corresponds to a sequence present on both Z and W chromosomes, while the other is W specific. Sequences of these two inserts show neither clear homology with other known sequences, nor an open reading frame. They cross-hybridize with the genomic DNA of Leporinusfriderici, but without sex-specific patterns. Twenty-four L. elongatus adults were sexed by gonadal observation, chromosomed examination and Southern hybridization with one or the other insert. Ten males and 11 females had chromosomes and hybridization patterns typical of their sex. One ZW female was recognized as a male with the W-specific probe. This was also the case for two unusual ZW males, one having a male hybridization pattern with the other probe. These three atypical individuals may result from single genetic exchanges between four regions of the Z and the W, giving rise to three atypical W chromosomes. Finding males with such atypical heterochromosomes in a female heterogametic species may indicate that a gradual transition occurs between the heterogametic systems.},
  subject      = {Physiologische Chemie},
  language  = {en}
}
@article{MaeuelerSchartlSchartl1993,
  author    = {M{\"a}ueler, Winfried and Schartl, Angelika and Schartl, Manfred},
  title     = {Different expression patterns of oncogenes and proto-oncogenes in hereditary and carcinogen-induced tumors of Xiphophorus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-61592},
  year      = {1993},
  abstract  = {Hereditary melanoma in Xiphophorus hybrids canying the melanoma·induclng Tu-Sd locus is caused by transcriptional activation of the Xmrk gene that resides at the Tu·Sd locus and encodes a novel member of receptor tyrosine kinases (RTK). ln this study, a total of 17 hereditary melanomas from various hybrid genotypes harbouring 7 different Tu alleles were also found to aver-express the correspondlng Xmrlc alleles. The Ievei of over-expression correlated with the degree of malignancy of the melanoma. ln addition, Xsrc expression was high ln many malignant melanomas. Expression pattems and Ieveis of the Xiphophorus EGF-receptor gene (Xerb B), the c-myc (Xmyc), and the PDGF (Xsls) gene(s) were not intriguing. Transcription of the ras gene(s) may be correlated to secondary events of melanoma progression. Expression pattems of Xfms, the Xiphophorus CSF-1 receptor homologue, can be explained by different contents of infiltrating macrophages in the tumors. ln carcinogen-induced tumors includlng one melanoma no significant expression of the Xmrk oncogene could be detected. Xsrc expression, however, was strikingly high. This indicates that activation of oncogenes other than Xmrk ls instrumental in tumorigenesls of neoplasia of non-hereditary origin.},
  subject      = {Physiologische Chemie},
  language  = {en}
}