When c-Src and v-Src were immunoprecipitated together from hamster fibroblasts transformed by Rous sarcoma virus containing v-src oncogene, the total Src activity was almost threefold higher compared to c-Src activity in the control cells. The activity of v-Src immunoprecipitated separately, however, accounting for only 40% of the total Src activity, indicating that c-Src is activated upon transformation. An increased activity of Csk was also found in RSV-transformed cells. It decreased upon serum stimulation in parallel with an increase in Src kinase activity. In nontransformed cells, serum stimulation induced an enhanced Csk activity, but no changes in c-Src activity were observed. This may suggest that Csk may have more functions in hamster fibroblasts, in addition to its inhibitory effect on c-Src.

• MeSH
• aktivace enzymů účinky léků   MeSH
• androstadieny farmakologie   MeSH
• buněčné linie MeSH
• C-terminální Src kinasa MeSH
• fibroblasty cytologie   účinky léků   metabolismus   MeSH
• inhibitory enzymů farmakologie   MeSH
• křečci praví MeSH
• krevní proteiny farmakologie   MeSH
• onkogenní protein pp60(v-src) genetika   metabolismus   MeSH
• protinádorová antibiotika farmakologie   MeSH
• protoonkogenní proteiny pp60(c-src) metabolismus   MeSH
• signální transdukce fyziologie   MeSH
• sirolimus farmakologie   MeSH
• skupina kinas odvozených od src-genu MeSH
• tyrosinkinasy metabolismus   MeSH
• virová transformace buněk fyziologie   MeSH
• viry ptačího sarkomu genetika   MeSH
• wortmannin MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• androstadieny MeSH
• C-terminální Src kinasa MeSH
• inhibitory enzymů MeSH
• krevní proteiny MeSH
• onkogenní protein pp60(v-src) MeSH
• protinádorová antibiotika MeSH
• protoonkogenní proteiny pp60(c-src) MeSH
• sirolimus MeSH
• skupina kinas odvozených od src-genu MeSH
• tyrosinkinasy MeSH
• wortmannin MeSH

Active, wild-type v-Src and its kinase-dead double Y416F-K295N mutant were expressed in hamster fibroblasts. Expression of the active v-Src induced activation of endogenous c-Src and increased general protein-tyrosine phosphorylation in the infected cells. Expression of the kinase-dead mutant induced hypophosphorylation of Tyr416 of the endogenous c-Src. The inactivation of c-Src was reversible, as confirmed by in vitro kinase activity of c-Src immunoprecipitated from the kinase-dead v-Src-expressing cells. Both activation and inactivation of c-Src may be explained by direct interaction of the v-Src and c-Src that may either facilitate transphosphorylation of the regulatory Tyr416 in the activation loop, or prevent it by formation of transient dead-end complexes of the Y416F-K295N mutant with c-Src. The interaction was also indicated by co-localization of v- and c-Src proteins in immunofluorescent images of the infected cells. These results suggest that dimerization of Src plays an important role in the regulation of Src tyrosine kinase activity.

• MeSH
• aktivace enzymů MeSH
• buněčné linie MeSH
• C-terminální Src kinasa MeSH
• fibroblasty metabolismus   MeSH
• lidé MeSH
• mutace MeSH
• mutageneze cílená MeSH
• onkogenní protein pp60(v-src) genetika   metabolismus   MeSH
• regulace genové exprese enzymů fyziologie   MeSH
• skupina kinas odvozených od src-genu MeSH
• tyrosinkinasy metabolismus   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• C-terminální Src kinasa MeSH
• CSK protein, human MeSH Prohlížeč
• onkogenní protein pp60(v-src) MeSH
• skupina kinas odvozených od src-genu MeSH
• tyrosinkinasy MeSH