Kano-Sueoka T, Sueoka N
Proc Natl Acad Sci U S A. 1969 Apr;62(4):1229-36. doi: 10.1073/pnas.62.4.1229.
The involvement of tRNA in cellular differentiation has been tested by analyzing aminoacyl-tRNA of Escherichia coli after phage T2 infection. One or two minutes after infection, half of one of the five leucine tRNA components (Leu-tRNA(1), CUG responding) undergoes a drastic structural change which leads to inactivity of both leucine acceptor activity and codon response. Whether or not the modification causes cessation of host protein synthesis without inhibiting phage-specific protein synthesis has been examined by analyzing polysome-bound leucine tRNA of E. coli before and after the phage infection. The results presented in this paper indicate that the amount of Leu-tRNA(1) used after infection was greatly reduced as compared to that used in noninfected cells. Studies of the in vitro protein-synthesizing system show that T2 mRNA rarely contains the CUG codon. A mechanism by which host mRNA translation is inhibited by the phage infection is proposed from this available information.
通过分析噬菌体T2感染后大肠杆菌的氨酰tRNA，对tRNA参与细胞分化进行了测试。感染后一到两分钟，五种亮氨酸tRNA成分之一（Leu-tRNA(1)，识别密码子CUG）的一半发生剧烈的结构变化，导致亮氨酸接受活性和密码子反应均失活。通过分析噬菌体感染前后大肠杆菌多核糖体结合的亮氨酸tRNA，研究了这种修饰是否会在不抑制噬菌体特异性蛋白质合成的情况下导致宿主蛋白质合成停止。本文给出的结果表明，与未感染细胞相比，感染后使用的Leu-tRNA(1)数量大幅减少。体外蛋白质合成系统研究表明，T2 mRNA很少包含CUG密码子。根据这些现有信息，提出了一种噬菌体感染抑制宿主mRNA翻译的机制。
