Regulation of protein synthesis by phosphorylation of eukaryotic initiation factor 2 alpha in intact reticulocytes and reticulocyte lysates.
Regulation of protein synthesis by phosphorylation of eukaryotic initiation factor 2 alpha in intact reticulocytes and reticulocyte lysates.
复制标题
通过完整网织红细胞和网织红细胞裂解物中真核起始因子 2α 的磷酸化调节蛋白质合成。
DOI：
10.1073/pnas.79.7.2147
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发表时间：
1982
影响因子：
11.1
通讯作者：
London,IM
中科院分区：
文献类型：
--
作者：
Leroux,A;London,IM
在完整的兔网织红细胞和网织红细胞裂解物中的研究进一步证明了真核细胞起始因子2α(eIF-2α)的磷酸化在真核细胞蛋白质合成起始调节中的功能作用。在用异烟酸肼抑制血红素合成的完整网织红细胞中，eIF-2α的磷酸化程度显著高于对照细胞。在缺乏血红素的网织红细胞裂解物和用双链RNA处理的裂解物中，eIF-2α的显著磷酸化发生在蛋白质合成被抑制之前；然而，总eIF-2α的很大一部分仍然没有磷酸化。这些发现表明，适度浓度的磷酸化eIF-2α足以抑制启动，它们表明eIF-2必须与之相互作用的因素之一可能是速率限制，特别是当eIF-2α被磷酸化时。
Studies in intact rabbit reticulocytes and reticulocyte lysates provide further evidence of a functional role for the phosphorylation of eukaryotic initiation factor 2 alpha (eIF-2 alpha) in the regulation of initiation of protein synthesis in eukaryotic cells. In intact reticulocytes treated with isonicotinic acid hydrazide to inhibit heme synthesis, the phosphorylation of eIF-2 alpha was significantly greater than in control cells. In heme-deficient reticulocyte lysates and in lysates treated with double-stranded RNA, significant phosphorylation of eIF-2 alpha occurred prior to the onset of inhibition of protein synthesis; a large proportion, however, of the total eIF-2 alpha remained unphosphorylated. These findings indicate that a modest concentration of phosphorylated eIF-2 alpha can suffice to inhibit initiation, and they suggest that one of the factors with which eIF-2 must interact may be rate limiting, especially when eIF-2 alpha is phosphorylated.