Tyrosylprotein kinase and phosphatase activities in membrane vesicles from normal and Rous sarcoma virus-transformed rat cells.
Tyrosylprotein kinase and phosphatase activities in membrane vesicles from normal and Rous sarcoma virus-transformed rat cells.
复制标题
正常和劳斯肉瘤病毒转化的大鼠细胞膜囊泡中酪氨酰蛋白激酶和磷酸酶的活性。
DOI：
10.1073/pnas.78.11.6689
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发表时间：
1981
影响因子：
11.1
通讯作者：
Brautigan,DL
中科院分区：
文献类型：
--
作者：
Gallis,B;Bornstein,P;Brautigan,DL
从正常细胞和Rous肉瘤病毒转化的大鼠细胞中分离的膜小泡具有相关的环-AMP非依赖性激酶，该激酶可磷酸化正常细胞的小泡中的MR 37,000蛋白，以及转化细胞的小泡中的MR 37,000、50,000和67,000蛋白。正常细胞和转化细胞囊泡中的蛋白质分别含有9%和77%的标记磷酸氨基酸，即磷酸酪氨酸。因此，分离囊泡并随后与[伽马-32P]ATP孵育可使蛋白质中标记的磷酸酪氨酸的比例(相对于其他磷酸氨基酸)比在完整细胞中发现的丰富两个数量级。在10微米锌离子(一种磷酸酪氨酸蛋白磷酸酶抑制剂)的存在下，这些蛋白质中的每一种的体外磷酸化都被增强。从这些研究看来，膜小泡可能是一个有价值的系统，用于检测蛋白质的转化特异性磷酸化。
Membrane vesicles; isolated from normal and Rous sarcoma virus-transformed rat cells, have an associated cyclic-AMP independent kinase that phosphorylates a Mr 37,000 protein in vesicles from normal cells and proteins of Mr 37,000, 50,000, and 67,000 in vesicles from transformed cells. Proteins in vesicles from normal and transformed cells contain 9% and 77%, respectively, of their labeled phospho amino acids as phosphotyrosine. Thus, isolation of vesicles and subsequent incubation with [gamma-32P]ATP enriches the proportion of labeled phosphotyrosine in proteins (relative to other phospho amino acids) by two orders of magnitude over that found in intact cells. The in vitro phosphorylation of each of these proteins is enhanced in the presence of 10 microM Zn2+, a phosphotyrosylprotein phosphatase inhibitor. From these studies it appears that membrane vesicles may be a valuable system for examination of transformation-specific phosphorylation of proteins.