Yonemoto W, Jarvis-Morar M, Brugge J S, Bolen J B, Israel M A
Proc Natl Acad Sci U S A. 1985 Jul;82(14):4568-72. doi: 10.1073/pnas.82.14.4568.
We have examined the in vitro phosphorylation of cellular src protein (pp60c-src) molecules associated with the polyoma virus middle-sized tumor antigen in polyoma virus-transformed cells. These pp60c-src molecules possessed an enhanced tyrosyl kinase activity, migrated aberrantly on NaDodSO4/polyacrylamide gels, and contained a novel site of tyrosine phosphorylation within the amino-terminal region of the molecule. The pp60c-src molecules not associated with the middle-sized tumor antigen were phosphorylated exclusively on a tyrosine residue within the carboxyl-terminal domain of pp60c-src. A similar modified form of the middle-sized tumor antigen-associated pp60c-src protein was detected in lysates from polyoma virus-transformed cells labeled in vivo with [32P]orthophosphate in the presence of sodium orthovanadate, an inhibitor of phosphotyrosyl phosphatases.
我们检测了多瘤病毒转化细胞中与多瘤病毒中肿瘤抗原相关的细胞src蛋白（pp60c-src）分子的体外磷酸化情况。这些pp60c-src分子具有增强的酪氨酰激酶活性，在十二烷基硫酸钠/聚丙烯酰胺凝胶上迁移异常，并且在分子的氨基末端区域含有一个新的酪氨酸磷酸化位点。与中肿瘤抗原不相关的pp60c-src分子仅在pp60c-src羧基末端结构域内的一个酪氨酸残基上被磷酸化。在存在磷酸酪氨酸磷酸酶抑制剂原钒酸钠的情况下，用[32P]正磷酸盐在体内标记的多瘤病毒转化细胞的裂解物中检测到了与中肿瘤抗原相关的pp60c-src蛋白的类似修饰形式。
