Immunological Detection of Cellular Targets for V-onc Gene Coded Tyrosine Kinases
The induction of transformed phenotype by retrovirus-infected cells is triggered by the action of unique genetic sequences, named onc genes. The protein products coded by a family of viral onc genes — v-src, v-ros, v-fps, v-yes, v-abl, v-fes — are known to be phosphokinases endowed with the unusual property of phosphorylating tyrosine residues (1). Since phosphotyrosine (P-TYR) constitutes less than 0.1% of the phosphoaminoacids in normal cells and it is only 5 to 10 fold increased in virally transformed cells, identification of cellular substrates for tyrosine kinases has been hampered by difficulties in distinguishing proteins containing P-TYR from those containing only phosphoserine (P-SER) and phosphothreonine (P-THR)(2).
KeywordsRous Sarcoma Virus Immunological Detection Adhesion Plaque Avian Sarcoma Virus Detergent Insoluble Fraction
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