Iwashita S, Kitamura N, Yoshida M
Virology. 1983 Mar;125(2):419-31. doi: 10.1016/0042-6822(83)90213-1.
A mutant of the Prague strain of Rous sarcoma virus (RSV) has two deletions near the 5'-terminus of its src gene. The mutant (dl 5) induced fusiform morphological transformation in chick embryo fibroblasts (CEF) in contrast to the round type morphological transformation induced by wild type (wt) RSV. The partially deleted src of dl5 was shown to code for a 52K protein which has tyrosine kinase activity as high as that of p60src. In dl 5-transformed cells, a 36K protein was heavily phosphorylated, while two proteins (MW = 55K and 57K) were dephosphorylated to the same extent as compared with cells transformed by wt RSV. The relative abundance of phosphotyrosine in vinculin was almost the same in both dl 5- and wt RSV-transformed cells after extended passage of dl 5-transformed cells without marked changes in their morphology. On the other hand, the amounts of vinculin and fibronectin in dl 5-transformed cells were twice those in wt RSV-transformed cells, although less than the amounts in uninfected cells. These results suggest that events leading to cellular morphological transformation are neither directly correlated with phosphorylation of the 36K protein, with dephosphorylation of the 55K and 57K proteins, nor with the level of phosphorylation of tyrosine residues in vinculin, but rather are correlated with the amount of vinculin and fibronectin.
劳氏肉瘤病毒（RSV）布拉格株的一个突变体在其src基因的5'末端附近有两个缺失。与野生型（wt）RSV诱导的圆形形态转化相反，该突变体（dl 5）在鸡胚成纤维细胞（CEF）中诱导梭形形态转化。已证明dl5部分缺失的src编码一种52K蛋白，其酪氨酸激酶活性与p60src一样高。在dl 5转化的细胞中，一种36K蛋白被大量磷酸化，而与wt RSV转化的细胞相比，两种蛋白（分子量分别为55K和57K）的去磷酸化程度相同。在dl 5转化的细胞长时间传代且其形态无明显变化后，dl 5和wt RSV转化的细胞中纽蛋白中磷酸酪氨酸的相对丰度几乎相同。另一方面，dl 5转化细胞中纽蛋白和纤连蛋白的量是wt RSV转化细胞中的两倍，尽管比未感染细胞中的量少。这些结果表明，导致细胞形态转化的事件既不与36K蛋白的磷酸化、55K和57K蛋白的去磷酸化直接相关，也不与纽蛋白中酪氨酸残基的磷酸化水平直接相关，而是与纽蛋白和纤连蛋白的量相关。
