Transforming potential of a human protooncogene (c-fps/fes) locus.

The protooncogene c-fps/fes is a single vertebrate locus homologous to both the fps transforming gene of Fujinami avian sarcoma virus and the fes transforming gene of two feline sarcoma virus isolates. The human c-fps/fes locus has been previously cloned and characterized. We report that a recombinant gene in which 3' human c-fps/fes sequences replace over 80% of the feline sarcoma virus fes sequences transforms NIH 3T3 mouse fibroblasts and encodes a protein kinase. Cells transformed by this recombinant possess increased phosphotyrosine levels. These observations demonstrate that a large carboxyl portion of a human c-fps/fes protein product can functionally complement a retroviral transforming protein.