van Dieijen G, Zipori P, van Prooijen W, van Duin J
Eur J Biochem. 1978 Oct 16;90(3):571-80. doi: 10.1111/j.1432-1033.1978.tb12637.x.
Antibodies against ribosomal protein S1 (anti-S1) have been used to determine the function of S1 in the partial reactions involved in the translation of MS2 RNA in vitro. Vacant ribosomes are fully sensitive to the antibodies, whereas elongating ribosomes are resistant. We have determined at which stage of translation the resistance to anti-S1 is acquired. We find that insensitivity to anti-S1 already arises upon mixing 30-S subunits with MS2 RNA. Apparently the two particles form a complex in which S1 is functionally protected against its antibody. Complex formation depends on elevated temperature, a suitable ionic environment and it is stimulated by the initiation factor IF-3. It does not depend on IF-1, IF-2 or fMet-tRNA. Thus ribosomes have the potential to recognize the messenger in the absence of fMet-tRNA. Protein S1 appears directly involved in this primary recognition reaction.
抗核糖体蛋白S1（抗-S1）抗体已被用于确定S1在体外MS2 RNA翻译相关部分反应中的功能。空载核糖体对该抗体完全敏感，而正在延伸的核糖体则具有抗性。我们已经确定了核糖体对抗-S1产生抗性是在翻译的哪个阶段。我们发现，在将30-S亚基与MS2 RNA混合时，核糖体就已经对抗-S1不敏感了。显然，这两种颗粒形成了一种复合物，其中S1在功能上受到保护而免受其抗体的作用。复合物的形成依赖于升高的温度、合适的离子环境，并且受到起始因子IF-3的刺激。它不依赖于IF-1、IF-2或fMet-tRNA。因此，核糖体在没有fMet-tRNA的情况下有识别信使的潜力。蛋白S1似乎直接参与了这一初级识别反应。
