TY  - JOUR
A1  - Barnekow, Angelika
A1  - Jahn, Reinhard
A1  - Schartl, Manfred
T1  - Synaptophysin: a substrate for the protein tyrosine kinase pp60c-src in intact synaptic vesicles
N2  - Expression of pp60 c-src, the first well defined proto-oncogene product, is developmentally regulated and tissue-specific, with neuronal tissues displaying high amounts of the c-src encoded pp60 c-src kinase activity. In the central nervous system pp60 s-src is preferentially expressed in regions characterized by a high content of grey matter and elevated density of nerve terminals. In this study we show for the first time a direct interaction between pp60 c-src and synaptophysin as a physiological target protein in neurons by demonstrating that endogenous pp60 c-src is able to phosphorylate synaptophysin (p38). p38 is a major constituent of the synaptic vesicle membrane protein and is thought to play a key role in the exocytosis of small synaptic vesicles and possibly small clear vesicles in neuroendocrine cells.
KW  - Synaptophysin
KW  - Synaptische Vesikel
KW  - Protein-Tyrosin-Kinasen
Y1  - 1990
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86168
ER  - 
TY  - JOUR
A1  - Schartl, Manfred
A1  - Holstein, Thomas
A1  - Robertson, Scott M.
A1  - Barnekow, Angelika
T1  - Preferential expression of a pp60c-src related protein tyrosine kinase activity in nerve cells of the early metazoan Hydra (Coelenterates)
N2  - It has been suggested that the proto-oncogene c-src plays a functional role in developing neurons, and in the mature nerve cells of higher vertebrales. The coelenterate Hydra represents tbe most primitive known organism possessing nerve cells. With Southern blot hybridizations we have demonstrated src-related sequences in Hydra. Antisera specific for the c-src gene product (pp60 c-src) of birds and mammals precipitate a protein from Hydra cell extracts with a tyrosine-specific protein kinase activity. Studies of tissues and cells fractionated from a temperature sensitive mutant of Hydra which is depleted of interstitial (including nerve) cells at tbe non-permissive temperature, have indicated the src-like kinase of Hydra to be preferentially expressed in nerve cells. The high conservation of structural features and of the expression pattern indicates a basic function for pp60c-src in neurons.
KW  - Protein-Tyrosin-Kinasen
KW  - Nervenzelle
KW  - Süßwasserpolypen
Y1  - 1989
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86179
ER  - 
TY  - JOUR
A1  - 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  -