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PubMed · 2439705

pp60c-src has less affinity for the detergent-insoluble cellular matrix than do pp60v-src and other viral protein-tyrosine kinases.

D M Loeb·J Woolford·K Beemon
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Abstract

A difference in affinity for a Nonidet P-40-insoluble cellular matrix was observed between the products of the viral and cellular src genes. It has previously been demonstrated that pp60v-src is associated with a detergent-insoluble matrix containing the cellular cytoskeleton (J. G. Burr, G. Dreyfuss, S. Penman, and J. M. Buchanan, Proc. Natl. Acad. Sci. USA 77:3484-3488, 1980). We observed a similar association of the transforming proteins of Fujinami sarcoma virus (P130gag-fps) and Yamaguchi 73 avian sarcoma virus (P90gag-yes), both of which are tyrosine-specific protein kinases. However, we found that the endogenous c-src product, pp60c-src, was not tightly bound to the detergent-insoluble matrix. This does not appear to have been due to differences in the cytoskeleton between transformed and nontransformed cells since pp60c-src was also solubilized by nonionic detergent in cells transformed by Rous sarcoma virus. This difference in the affinities of the v-src and c-src products for cytoskeletal proteins may contribute to the inability of pp60c-src to transform cells.

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Avian Sarcoma VirusesCell CompartmentationCytoskeletonDetergentsMyristic AcidMyristic AcidsOncogene Protein pp60(v-src)Protein-Tyrosine KinasesProto-Oncogene ProteinsProto-Oncogene Proteins pp60(c-src)Retroviridae ProteinsSolubilityTime FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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D M Loeb, J Woolford, K Beemon. 1987. pp60c-src has less affinity for the detergent-insoluble cellular matrix than do pp60v-src and other viral protein-tyrosine kinases.. https://doi.org/10.1128/jvi.61.8.2420-2427.1987

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