Hinnebusch A G
Section on Molecular Genetics of Lower Eukaryotes, National Institute of Child Health and Human Development, Bethesda, MD 20892, USA.
Semin Cell Biol. 1994 Dec;5(6):417-26. doi: 10.1006/scel.1994.1049.
Phosphorylation of translation initiation factor 2 alpha is a highly conserved mechanism for down-regulating protein synthesis in response to starvation or stress. The yeast eIF-2 alpha kinase GCN2 is stimulated by deprivation for amino acids or purines. In addition to inhibiting general protein synthesis, GCN2 specifically stimulates translation of GCN4, a transcriptional activator of amino acid biosynthetic genes. HRI is an eIF-2 alpha kinase that is activated in rabbit reticulocytes by heme-deprivation and stress conditions that elicit the heat-shock response. The eIF-2 alpha kinase DAI is activated by double-stranded RNA during viral infections and is an important component of the interferon response. DAI has also been implicated as a tumor suppressor. These protein kinases provide an important means of coupling the rate of protein synthesis and cell division to environmental conditions.
翻译起始因子2α的磷酸化是一种高度保守的机制，用于在饥饿或应激反应中下调蛋白质合成。酵母eIF-2α激酶GCN2受到氨基酸或嘌呤缺乏的刺激。除了抑制一般蛋白质合成外，GCN2还特异性地刺激GCN4的翻译，GCN4是氨基酸生物合成基因的转录激活因子。HRI是一种eIF-2α激酶，在兔网织红细胞中由血红素缺乏和引发热休克反应的应激条件激活。eIF-2α激酶DAI在病毒感染期间被双链RNA激活，是干扰素反应的重要组成部分。DAI也被认为是一种肿瘤抑制因子。这些蛋白激酶提供了一种重要手段，将蛋白质合成和细胞分裂的速率与环境条件联系起来。
