有三种已知的原核释放因子涉及翻译的终止。
- RF1 识别终止密码子 UAA 和 UAG;
- RF2 识别终止密码子 UAA 和 UGA;
- RF3 不识别终止密码子,而是与其他释放因子一起释放肽链终止翻译。
释放因子形成的构象与tRNA类似,可以进入核糖体的A位,与mRNA上的终止密码子进行识别[1]。一旦RF1(或RF2)和RF3结合到核糖体上,核糖体的大小亚基就会解离,多肽链被释放,从而完成翻译[2]。
- ^ Brown, CM; Tate, WP. Direct recognition of mRNA stop signals by Escherichia coli polypeptide chain release factor two. The Journal of Biological Chemistry. 1994, 269 (52): 33164–70. PMID 7806547.
- ^ Scarlett, D.-J. G.; McCaughan, KK; Wilson, DN; Tate, WP. Mapping Functionally Important Motifs SPF and GGQ of the Decoding Release Factor RF2 to the Escherichia coli Ribosome by Hydroxyl Radical Footprinting. IMPLICATIONS FOR MACROMOLECULAR MIMICRY AND STRUCTURAL CHANGES IN RF2. Journal of Biological Chemistry. 2002, 278 (17): 15095–15104. PMID 12458201. doi:10.1074/jbc.M211024200.