7272
1984
eng
conferenceobject
1
2013-09-03
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Xiphophorus as an in vivo model for studies on oncogenes
The capacity of Xiphophorus to develop neoplasia can be formally assigned to a "tumor gene" (Tu), which appears to be a normal part of the genome of all individuals. The wild fish have evolved population-specific and cell type-specific systems of regulatory genes (R) for Tu that protect the fish from neoplasia. Hybridization of members of different wild populations in the laborstory followed by treatment of the hybrids with carcinogens led to disintegration of the R systems permitting excessive expression of Tu and thus resulting in neoplasia. Certain hybrids developed neoplasia even spontaneously. Observations on the genuine phenotypic effect of the derepressed Tu in the early embryo indicated an essential normal function of this oncogene in cell differentiation, proliferation and cell-cell communication. Tu appeared to be indispensable in the genome but may also be present in accessory copics. Recently, c-src, the cellular homolog of the Rous sarcoma virus oncogene v-src, was detected in Xiphophorus. The protein product of c-src, pp60c-src, was identified and then examined by its associated kinase activity. This pp60c-src was found in all individuals tested, but, depending on the genotype, its kinase activity was different. The genetic characters of c-src, such as linkage relations, dosage relations, expression, etc., correspond to those of Tu. From a systematic study which showed that pp60c-src was present in all metazoa tested ranging from mammals down to sponges, we concluded that c-src has evolved with the multicellular organization of animals. Neoplasia of animals and humans is a characteristic closely related to this evolution. Our data showed that small aquariurn fish, besides being used successfully because they are time-, space-, and money-saving systems for carcinogenicity testing, are also highly suitable for basic studies on neoplasia at the populational, morphological, developmental, cell biological, and molecular levels.
8073
urn:nbn:de:bvb:20-opus-86398
In: Use of small fish species in carcinogenity testing / ed. Karen L. Hoover. - Bethesda, Md: US Dep. of Health and Human Services, Public Health Service, National Institutes of Health; 1984. - S. 97-109. - (National Cancer Institute <Bethesda, Md.>: Monographs ; 65)
Deutsches Urheberrecht
Fritz Anders
Manfred Schartl
Angelika Barnekow
deu
swd
Schwertkärpfling
deu
swd
In vivo
deu
swd
Onkogen
Chemie und zugeordnete Wissenschaften
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/7272/Schartl_7272.pdf
5375
1990
eng
article
1
2011-12-12
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Oncofetal antigen in Xiphophorus detected by monoclonal antibodies directed against melanoma-associated antigens
Monoclonal antlbodies (MAbs) directed against Xiphophorus melanoma cells were deve(oped and tested by lndirect immunofluorescence and Immunoperoxidase staining for reactivity with a panel of I 5 allogeneic tissues and 12 allogeneic cell llnes. The reactivity of such MAbs was restricted to melanoma cells from tumor biopsies and melanoma-derived cell lines. ln addition, all embryonie cells of all histiotypes from developmental stages later than mld·organogenesis and from corresponding short term in vitro cultures reacted with these MAbs. ln contrast, normal tissues and organs from adult fish dlsplayed no reactivity, thus implying that the melanoma-associated antigens detected by the MAbs described are oncofetal antigens.
urn:nbn:de:bvb:20-opus-61784
6178
In: International journal of cancer (1990 ) , 45, 136-142
Deutsches Urheberrecht
Gerd Clauss
Christoph Winkler
Jürgen Lohmeyer
Fritz Anders
Manfred Schartl
deu
swd
Physiologische Chemie
Chemie und zugeordnete Wissenschaften
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/5375/Schartl36.pdf
7097
1985
eng
conferenceobject
1
2013-08-23
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An ultrastructural study of melanoma in Xiphophorus
Melanotic melanoma (MM) of Xiphophorus (Teleostei: Poeciliidae) was studied by conventional preparations and freeze-etch preparations for electron microscopy. MM of Xiphophorus exhibits tightly packed pigment cells with prominent dendritic processes and interdigitations of their plasma membranes. The most impressive feature of MM cells is the occurrence of Iarge lobulated nuclei with numerous nuclear pores and some nuclear pockets. Abundant spheroidal or ellipsoidal melanosomes (diameter 200-650 nm) and vesicular structures are distributed throughout the cellular dendrites, whereas the perinucJear cytoplasm is free of melanosomes.
A further characteristic feature of melanoma cells in fish is the occurrence of melanosome complexes (i.e., "compound melanosomes"). These melanosome complexes consist of a few to numerous melanosomes, which are enveloped by a separate rnembrane. Pinocytotic vesicles couJd be demonstrated with distinct differences in frequency and distribution patterns, indicating differences in the metabolic activities of the cells in the same melanoma. Intercellular junctions are lacking in the MM cells.
The conventional TEM technique showed clear advantages in the demonstration of intemal architecture of organelles, whereas FE bad considerable potential in respect to the visualization of membrane surface specializations.
8045
urn:nbn:de:bvb:20-opus-70978
In: Biological, Molecular and Clinical Aspects of Pigmentation : proceedings of the XIIth Internat. Pigment Cell Conference, Gießen, Federal Republic of Germany Pigment cell nineteen hundred and eighty-five / ed. by Joseph T. Bagnara. - [Tokyo]: Univ. of Tokyo Pr., 1985. - S. 457-464. - ISBN 4-13-068114-1
Deutsches Urheberrecht
Rüdiger Riehl
Manfred Schartl
Fritz Anders
deu
swd
Schwertkärpfling
deu
swd
Krebs <Medizin>
deu
swd
Ultrastruktur
Chemie und zugeordnete Wissenschaften
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/7097/Schartl_7097.pdf