THE CONVERSION OF EIF-2.GDP TO EIF-2.GTP BY EIF-2B REQUIRES MET-TRANSFER RNAFMET
THE CONVERSION OF EIF-2.GDP TO EIF-2.GTP BY EIF-2B REQUIRES MET-TRANSFER RNAFMET
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DOI：
10.1016/0006-291x(91)92109-w
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发表时间：
1991-12-31
影响因子：
3.1
通讯作者：
HESSEFORT, SM
中科院分区：
文献类型：
--
作者：
GROSS, M;RUBINO, MS;HESSEFORT, SM
We have investigated why the recycling of eIF-2 廉 DP to eIF-2 廉 TP, mediated by the guanine nucleotide exchange factor eIF-2B, is rapid in rabbit reticulocyte lysate, reconstituted for optimal protein synthesis, but slow in an isolated reaction with purified eIF-2B. We have found that purified eIF-2B dissociates eIF-2 愴 3 H] GDP as efficiently in the presence of GTP as it does in the presence of GDP provided Met-tRNA f Met is added. tRNA f Med is ineffective, and there is no Met-tRNA f Met requirement for exchange with GDP. Exchange of eIF-2 bound GDP for GTP is completely dependent upon Met-tRNA f Met in the presence of ATP, suggesting that under physiological conditions efficient recycling of eIF-2 廉 DP to eIF-2 廉 TP requires conversion of the latter, a relatively unstable complex, to a more stable Met-tRNA f Met 搪 IF-2 廉 TP complex.