Pellman D, Garber E A, Cross F R, Hanafusa H
Proc Natl Acad Sci U S A. 1985 Mar;82(6):1623-7. doi: 10.1073/pnas.82.6.1623.
We have recently demonstrated that an NH2-terminal sequence required for myristylation and membrane association of the Rous sarcoma virus transforming protein, p60src, is contained within amino acids 2-14 [Cross, F.R., Garber, E. A., Pellman, D. & Hanafusa, H. (1984) Mol. Cell. Biol. 4, 1834-1842]. This sequence is also required for cell transformation. We have now constructed five mutants of Rous sarcoma virus that contain alterations in the src sequence coding for these 14 amino acids. Mutants encoding src proteins with a peptide insertion between amino acids 1 and 2, or peptide substitutions for amino acids 2-4, 3-4, or 7-15, were transformation-defective. The src proteins of these mutants differed from the wild-type protein in that they were not myristylated and did not fractionate with the plasma membrane of infected cells. The fifth mutant encoded a src protein with a short peptide substituted for amino acids 11-15. This protein was myristylated and plasma membrane associated, and the virus transformed cells. We therefore conclude that a sequence required for myristylation and membrane association of p60src is located within the first 7-10 amino acids of the src protein, and that p60src myristylation and membrane association are required for cell transformation. Consistent with this idea, we have isolated four transforming revertants from one of the transformation-defective mutants. The src proteins of all four revertants were found to be myristylated and membrane associated.
我们最近证明，劳氏肉瘤病毒转化蛋白p60src的肉豆蔻酰化和膜结合所需的NH2末端序列包含在氨基酸2 - 14中[克罗斯，F.R.，加伯，E.A.，佩尔曼，D.和花房，H.（1984年）《分子细胞生物学》4，1834 - 1842]。该序列对于细胞转化也是必需的。我们现在构建了五个劳氏肉瘤病毒突变体，它们在编码这14个氨基酸的src序列中存在改变。编码在氨基酸1和2之间插入肽段，或对氨基酸2 - 4、3 - 4或7 - 15进行肽段替换的src蛋白的突变体是转化缺陷型的。这些突变体的src蛋白与野生型蛋白的不同之处在于它们没有被肉豆蔻酰化，并且在感染细胞的质膜中不能分级分离。第五个突变体编码一种src蛋白，其中氨基酸11 - 15被一个短肽所取代。这种蛋白被肉豆蔻酰化并与质膜相关联，并且该病毒能转化细胞。因此我们得出结论，p60src的肉豆蔻酰化和膜结合所需的序列位于src蛋白的前7 - 10个氨基酸内，并且细胞转化需要p60src的肉豆蔻酰化和膜结合。与此观点一致的是，我们从其中一个转化缺陷型突变体中分离出了四个转化回复突变体。发现所有四个回复突变体的src蛋白都被肉豆蔻酰化并与膜相关联。
