An insulin-stimulated (ribosomal S6) protein kinase from soluble extracts of H4 hepatoma cells.
An insulin-stimulated (ribosomal S6) protein kinase from soluble extracts of H4 hepatoma cells.
复制标题
来自 H4 肝癌细胞可溶性提取物的胰岛素刺激（核糖体 S6）蛋白激酶。
DOI：
10.1016/0003-9861(86)90205-5
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发表时间：
1986
影响因子：
3.9
通讯作者：
Avruch,J
中科院分区：
文献类型：
--
作者：
Nemenoff,RA;Gunsalus,JR;Avruch,J
Insulin stimulates the phosphorylation of the 40 S ribosomal subunit protein, S6, in intact32P-labeled H4IIE-C3 cells, a rat hepatoma line. Cell-free cytosolic extracts from H4 cells exhibit a 5- to 10-fold increase in S6 protein kinase activity (measured by transfer of32P to exogenous 40 S rat liver ribosomal subunits) when prepared from cells exposed to insulin prior to homogenization. Stimulation of S6 phosphorylation in intact cells and activation of S6 protein kinase in cell-free extracts are both detectable within 2 min after insulin, and are maximally stimulated by 10 min. Half-maximal stimulation is observed at 10−11minsulin. The stimulated S6 kinase activity requires ethylene glycol bis(β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid to be present during the kinase assay for full expression. Despite the presence of a 5- to 10-fold increase in S6 protein kinase activity, the extracts from insulin-treated cells exhibit no stimulated kinase activity toward casein, histone, or ATP-citrate lyase assayed under the conditions employed for S6. Thus, insulin mediates the rapid activation of protein kinase specific for ribosomal protein S6 by an as yet unidentified mechanism.
