Beuzard Y, London I M
Proc Natl Acad Sci U S A. 1974 Jul;71(7):2863-6. doi: 10.1073/pnas.71.7.2863.
Protein synthesis in reticulocyte lysates ceases abruptly in the absence of added hemin or in the presence of double-stranded RNA. A similar effect of double-stranded RNA is observed in Krebs II ascites cell-free systems translating exogenous globin mRNA. The shut-off of protein synthesis is due to inhibition of initiation and can be prevented or reversed by addition of the initiation factor preparation M(3). Preparations of M(1), M(2), and dissociation factor are ineffective under these conditions. The effects of added hemin, M(3), and globin mRNA on the synthesis of alpha and beta globin chains have been studied in the reticulocyte and ascites cell extracts. When the concentration of M(3) is rate limiting, the synthesis of beta chains exceeds that of alpha chains. When the concentration of mRNA is rate limiting, synthesis of alpha and beta chains is more nearly equal.
在没有添加血红素或存在双链RNA的情况下，网织红细胞裂解物中的蛋白质合成会突然停止。在翻译外源性珠蛋白mRNA的克雷布斯II腹水无细胞系统中也观察到双链RNA有类似的作用。蛋白质合成的关闭是由于起始过程受到抑制，添加起始因子制剂M(3)可以预防或逆转这种抑制。在这些条件下，M(1)、M(2)制剂和解离因子无效。已经在网织红细胞和腹水细胞提取物中研究了添加的血红素、M(3)和珠蛋白mRNA对α和β珠蛋白链合成的影响。当M(3)的浓度成为限速因素时，β链的合成超过α链。当mRNA的浓度成为限速因素时，α链和β链的合成则更为接近相等。
