Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen OPUS4-5287 Wissenschaftlicher Artikel Malitschek, Barbara; Wittbrodt, Joachim; Fischer, Petra; Lammers, Reiner; Ullrich, Axel; Schartl, Manfred Autocrine stimulation of the Xmrk receptor tyrosine kinase in Xiphophorus melanoma cells and identification of a source for the physiological ligand The melanoma·inducing gene of Xiphophorus fish encodes the Xmrk receptor tyrosine kinase. U sing a highly specific antiserum p~oduced against the recombinant receptor expressed with a baculovirus, it is shown that Xmrk is the most abundant phosphotyrosine protein in fish melanoma and thus highly activated in the tumors. Studies on a melanoma cellline revealed that these cells produce an activity that considerably stimulates receptor autophosphorylation. The stimulating activity induces receptor down-regulation and can be depleted from the melanoma cellsupernatant by the immobilized recombinant receptor protein. The fish melanoma cells can thus be considered autocrine tumor cells providing a source for future purification and characterization of the Xmrk ligand. 1994 urn:nbn:de:bvb:20-opus-61551 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5953 Wissenschaftlicher Artikel Schartl, A.; Dimitrijevic, N.; Schartl, Manfred Evolutionary origin and molecular biology of the melanoma-inducing oncogene of Xiphophorus No abstract available 1994 urn:nbn:de:bvb:20-opus-61954 Theodor-Boveri-Institut für Biowissenschaften OPUS4-6975 Teil eines Buches Altschmied, Joachim; Schartl, Manfred Genetics and molecular biology of tumour formation in Xiphophorus No abstract available. 1994 urn:nbn:de:bvb:20-opus-69752 Theodor-Boveri-Institut für Biowissenschaften OPUS4-7281 Wissenschaftlicher Artikel Winkler, Christoph; Wittbrodt, Joachim; Lammers, Reiner; Ullrich, Axel; Schartl, Manfred Ligand-dependent tumor induction in medakafish embryos by a Xmrk receptor tyrosine kinase transgene Xmrk encodes a subclass 1 receptor tyrosine kinase (RTK) which has been cloned from the melanomainducing locus Tu of the poeciliid fish Xiphophorus. To demonstrate a high oncogenic potential in vivo we transferred the gene into early embryos of the closely related medakafish. Ectopic expression of the Xmrk oncogene under the control of a strong, constitutive promoter (CMVTk) led to the induction of embryonic tumors with high incidence, after short latency periods, and with a specific pattern of affected tissues. We demonstrate ligand-dependent transformation in vivo using a chimeric receptor consisting of the extracellular and transmembrane domains of the human EGF receptor (HER) and the cytoplasmatic domain of Xmrk. Expression of the chimeric receptor alone does not lead to ldnase activation or induction of tumors. Coexpression of the chimera with its corresponding ligand, human transforming growth factor alpha (bTGF(X), however, results in the activation of the chimeric RTK. In injected fish embryos the induction of the neoplastic growth is observed with similar incidence and tissue distribution as in embryos carrying the native Xmrk oncogene suggesting that the ligand as well as factors downstream of tbe RTK are required for tumor formation. In this study we show single-step induction of tumors by ectopic expression of RTKs in vivo substantiating tbe significance of autocrine stimulation in RTK induced tumors in vertebrales. 1994 urn:nbn:de:bvb:20-opus-87107 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5314 Wissenschaftlicher Artikel Erbelding-Denk, Claudia; Schroder, Johannes H.; Schartl, Manfred; Nanda, Indrajit; Schmid, Michael; Epplen, Jörg T. Male polymorphism in Limia perugiae (Pisces: Poeciliidae) The male-polymorphic poeciliid fish, Limia perugiae, a small teleostean endemic to the southeast of the Caribbean island Hispafiola, consists of three male size morphs with uniform females. Large males differentiate at a size va:rying between 25 and 38 mm; intermediate males, between 21 and 25 mm. Under competition, !arge males exhibit an elaborate courtship display, whereas small males show only a sneak-chase behavior. Intermediate males adapt their tactics to the respective competitors. However, all malemorphs can switch from courtship display to sneak-chase behavior. In large mating groups with four males of different size and five or six virgin females, large dominant a-males as weil as small subordinate \(\delta\)-males did not produce any offspring. Unexpectedly, all progeny were sired exclusively by the intemediate subordinate ß- and \(\gamma\)-males. Breeding experiments with the three male morphs can best be explained by a model of Y -linked genes for small and !arge size which are both suspended by the activity of an autosomal recessive repressor responsible for the development of intermediate males. The dominant allele of the recessive repressor, in either its homoorits heterozygous state, activates the Y-chromosomal genes for !arge or small size, respectively. Accordingly, intermediate males may produce male offspring of all size classes, depending on the presence of either the Y-linked gene or the autosomal repressor. 1994 urn:nbn:de:bvb:20-opus-61573 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5955 Wissenschaftlicher Artikel Lubjuhn, T.; Schartl, Manfred; Epplen, J. T. Methodik und Anwendungsgebiete des genetischen Fingerabdruckverfahrens No abstract available 1994 urn:nbn:de:bvb:20-opus-61978 Theodor-Boveri-Institut für Biowissenschaften OPUS4-6974 Konferenzveröffentlichung Schreibman, Martin P.; Schartl, Manfred; Kallman, Klaus D.; Magliulo-Cepriano, Lucia Molecular approaches to study the genetic regulation of the fish reproductive system No abstract available. 1994 urn:nbn:de:bvb:20-opus-86679 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5286 Wissenschaftlicher Artikel Götz, Rudolf; Köster, Reinhard; Winkler, Christoph; Raulf, Friedrich; Lottspeich, Friedrich; Schartl, Manfred; Thoenen, Hans Neurotrophin-6 is a new member of the nerve growth factor family DURING vertebrale development, many neurons depend for survival and differentiation on their target cells\(^{1-3}\). The best documented mediator of such a retrograde trophic action is the neurotrophin nerve growth factor (NGF)\(^1\). NGF and the other known members of tbe neurotrophin family, brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT -3) and neurotrophin-4/5 (NT -4/5) are conserved as distinct genes over large evolutionary distances\(^{4 -6}\). Here we report the cloning of neurotrophin-6 (NT -6), a new member of this family from the teleost fish Xiphophorus. NT -6 distinguishes itself from the other known neurotrophins in that it is not found as a soluble protein in the medium of producing cells. The addition of heparin (but not chondroitin) effects the release of NT -6 from cell surface and extracellular matrix molecules. Recombinant purified NT -6 has a spectrum of actions similar to NGF on chick sympathetic and sensory neurons, albeit with a lower potency. NT -6 is expressed in tbe embryonie valvulla cerebelli; expression persists in some adult tissues. The interaction of NT-6 with heparin-binding molecuJes may modulate its action in the nervous system . 1994 urn:nbn:de:bvb:20-opus-61544 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5288 Wissenschaftlicher Artikel Meyer, Axel; Morrissey, Jean M.; Schartl, Manfred Recurrent origin of a sexually selected trait in Xiphophorus fishes inferred from a molecular phylogeny DARWIN\(^1\) believed that sexual selection accounts for the evolution of exaggerated male ornaments, such as the sword-like caudal fin extensions of male fishes of the genus Xiphophorus, that appear detrimental to survival. Swordtails continue to feature prominently in empirical work and theories of sexual selection; the pre-existing bias hypothesis has been offered as an explanation for the evolution of swords in these fishes\(^{2,3}\). Based upon a largely morphological phylogeny, this hypothesis suggests that female preference to mate with sworded males arose in ancestrally swordless species, thus pre-dating the origin of the sword itself and directly driving its evolution. Here we present a molecular phylogeny (based on mitochondrial and nuclear DNA sequences) of Xiphophorus which differs from the traditional one: it indicates that the sword originated and was lost repeatedly. Our phylogeny suggests that the ancestor of the genus is more likely to have possessed a sword than not, thus questioning the applicability of the pre-existing bias hypothesis as an explanation for the cvolution of this sexually selected trait. 1994 urn:nbn:de:bvb:20-opus-61569 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5315 Wissenschaftlicher Artikel Nakayama, Ichiro; Foresti, Fausto; Tewari, Rita; Schartl, Manfred; Chourrout, Daniel Sex chromosome polymorphism and heterogametic males revealed by two cloned DNA probes in the ZW/ZZ fish Leporinus elongatus 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. 1994 urn:nbn:de:bvb:20-opus-61583 Theodor-Boveri-Institut für Biowissenschaften OPUS4-5954 Konferenzveröffentlichung Gotz, R.; Schartl, Manfred The conservation of neurotrophic factors during vertebrate evolution No abstract available 1994 urn:nbn:de:bvb:20-opus-61964 Theodor-Boveri-Institut für Biowissenschaften