CHARACTERIZATION OF 3 PROTEINS INVOLVED IN POLYPEPTIDE CHAIN TERMINATION
CHARACTERIZATION OF 3 PROTEINS INVOLVED IN POLYPEPTIDE CHAIN TERMINATION
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DOI：
10.1101/sqb.1969.034.01.053
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发表时间：
1969-01-01
期刊：
影响因子：
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通讯作者：
KLEIN, HA
中科院分区：
文献类型：
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作者：
CAPECCHI, MR;KLEIN, HA
在每个延伸阶段，生长的多肽链通过最近掺入的氨基酸残基的转移RNA与核糖体-信使RNA复合物结合（吉尔伯特，1963; Bretscher，1963）。当链完成时，最后一个多肽转移RNA（tRNA）酯键被切割，从tRNA中释放出链，从而从核糖体复合物中释放出来。当核糖体在沿着信使RNA（mRNA）移动的过程中到达链终止信号时，发生这种水解。阐明多肽链终止机制的第一步是识别此类信号。纯遗传方法表明密码子UAA、UAG和UGA可作为终止信号（Brenner，斯特雷顿和卡普兰，1965;魏格特和加伦，1965;萨姆布鲁克，范和Brenner，1967; Zipser，1967）。如果通过突变，这样一个密码子出现在顺反子的内部，那么在遗传改变的时候，多肽链会提前终止（Sarabhai，斯特雷顿，Brenner和Bolle，1964）。这种密码子分配得到了无细胞研究的支持，该研究表明，与均聚物不同，随机U，A和U，A，G共聚物指导多肽的合成，其中一些多肽从tRNA中释放出来（Bretscher，Goodman，Menninger和Smith，1965; Takanami和u，1965; Ganoza和Nakamoto，1966）。UAA可以触发多肽链终止的一个更直接的证实是多核糖核苷酸AUGUUUUAAA...指导了释放的二肽N-甲酰基甲硫氨酰基（F-met-）苯丙氨酸的合成（Last，Stanley，Salas，Hille，Wahba和Ochoa，1967）。为了进一步阐明FIOURE I的作用机制。概述控制R17 NH 2-末端外壳蛋白六肽F-met-Ala-Ser-Asn-Phe-14 C-Thr合成及其从核糖体mRNA-pcptidyl tRNA复合物中释放所需的步骤。T和R1是E。大肠杆菌因子分别为多肽链的延伸和释放所需。
At each stage of elongation, the growing polypeptide chain is bound to the ribosome-messenger RNA complex through the transfer RNA of the most recently incorporated amino acid residue (Gilbert, 1963; Bretscher, 1963). When the chain is complete, the last polypeptide-transfer RNA (tRNA) ester linkage is cleaved, releasing the chain from the tRNA and thus from the ribosomal complex. This hydrolysis occurs when the ribosome in the course of moving along the messenger RNA (mRNA) reaches a chain terminating signal. The first step in elucidating the mechanism of polypeptide chain termination was to identify such signals. A purely genetic approach indicated that the codons UAA, UAG, and UGA could act as termination signals (Brenner, Stretton, and Kaplan, 1965; Weigert and Garen, 1965; Sambrook, Fan, and Brenner, 1967; Zipser, 1967). If by mutation such a codon appears, in phase, in the interior of a cistron, premature polypeptide chain termination occurs at the point of genetic alteration (Sarabhai, Stretton, Brenner, and Bolle, 1964). This codon assignment was supported by cell-free studies which showed that random U, A and U, A, G copolymers, unlike the homopolymers, directed the synthesis of polypeptides, some of which were released from the tRNAs (Bretscher, Goodman, Menninger, and Smith, 1965; Takanami and u 1965; Ganoza and Nakamoto, 1966). A more direct confirmation that UAA can trigger polypeptide chain termination was the demonstration that the polyribonucleotide AUGUUUUAAA... directed the synthesis of the released dipeptide N-formylmethionyl (F-met-) phenylalanine (Last, Stanley, Salas, Hille, Wahba and Ochoa, 1967). In order to further decipher the mechanism ofFIOURE I. Outline of the steps required to control the synthesis of the R17 NH2-terminal coat protein hexapeptide, F-met-Ala-Ser-Asn-Phe-14C-Thr, and its release from the ribosomemRNA-pcptidyl tRNA complex. T and R 1 are E. coli factors required for elongation and release of the polypeptide chain respectively.