Homology between phosphotyrosine acceptor site of human c-abl and viral oncogene products

Abstract

The human homologues of several independent viral oncogenes, each of which encodes tyrosine-specific protein kinases, have been identified^1,2. Of these, three (v-src, v-yes and v-fes/fps) are known to exhibit considerable sequence homology, particularly in the regions of their phosphorylation acceptor sites^3–5. In the present study, sequences encoding the tyrosine phosphorylation acceptor sites of the Abelson murine leukaemia virus oncogene, v-abl, and its human cellular homologue, c-abl, have been identified and their nucleic acid sequences determined. Our results establish extensive homology between this region of c-abl and acceptor domains of the v-src^3,6, v-yes⁶ and v-fes/fps^4,5 family of viral oncogenes, as well as more distant relatedness to the catalytic chain of the mammalian cyclic AMP-dependent protein kinase⁷. These findings suggest that, of the homologues of retroviral oncogenes with tyrosine protein kinase activity examined to date, all were probably derived from a common progenitor and may represent members of a diverse family of cellular protein kinases.