Activities of the src-gene Product of Avian Sarcoma Virus

Avian sacroma viruses (ASVs) produce malignant tumors in susceptible avian and mammalian hosts and can transform cells in tissue culture. A single gene, src, in the viral genome appears to be responsible for the various coordinated changes in cell division, shape, and metabolism that occur upon transformation (Hana-fusa 1977). Although genetic analyses indicate that the product of the ASV src gene is a single protein (Wyke et al. 1974), studies with conditional src-gene mutants have suggested that the src-gene product has several different argets within the cell, accounting for pleiotypic effects that occur upon transformation (Weber and Friis 1979). Knowledge of these targets and the mechanisms by which the src-gene product achieves its diverse effects would be particularly valu-