Franco R S, Hogg J W, Martelo O J
Am J Hematol. 1981;11(1):9-18. doi: 10.1002/ajh.2830110103.
An inhibitor of globin translation initiation that is activated under heme-deficient conditions and whose activity is associated with phosphorylation of the 38,000 dalton (alpha) subunit of the initiation factor eIF-2 has been previously described in rabbit reticulocytes. We describe here an analogous enzyme in human reticulocytes. The human enzyme can be activated in intact reticulocytes under conditions of heme synthesis inhibition or by incubation of lysates in the absence of hemin. Addition of hemin to lysates prevents activation of the eIF-2 alpha kinase. The partially purified kinase is associated with inhibition of globin synthesis in a rabbit cell-free system and phosphorylates the small subunit of highly purified rabbit eIF-2. We conclude that human reticulocytes contain a protein kinase that is analogous to the rabbit HCR and that may play a role in clinical heme deficiency states. l
一种在血红素缺乏条件下被激活的珠蛋白翻译起始抑制剂，其活性与起始因子eIF-2的38,000道尔顿（α）亚基的磷酸化有关，此前已在兔网织红细胞中被描述。我们在此描述人网织红细胞中的一种类似酶。人酶可在血红素合成抑制条件下的完整网织红细胞中被激活，或通过在无血红素的情况下孵育裂解物来激活。向裂解物中添加血红素可阻止eIF-2α激酶的激活。部分纯化的激酶在兔无细胞系统中与珠蛋白合成的抑制相关，并使高度纯化的兔eIF-2的小亚基磷酸化。我们得出结论，人网织红细胞含有一种与兔HCR类似的蛋白激酶，可能在临床血红素缺乏状态中起作用。
