GLYCOPROTEIN TYROSINE PHOSPHORYLATION IN ROUS-SARCOMA VIRUS-TRANSFORMED CHICKEN-EMBRYO FIBROBLASTS

The level of tyrosine phosphorylation of cellular glycoproteins isolated by wheat germ agglutinin chromatography in cells infected with a variety of kinase-positive/transformation-defective src mutants was examined in an effort to identify cellular membrane proteins whose phosphorylation correlates with phenotypic transformation. We have identified two glycoproteins, with molecular masses of 95 and 135 kilodaltons, whose phosphorylation correlates with morphological transformation, growth in soft agar, and an increase in the rate of 2-deoxyglucose uptake. The strong correlation obtained between transformation and phosphorylation of these proteins suggests that they may be substrates for pp60(src) which are important in the process of transformation.