PROGRAMMED RIBOSOMAL FRAMESHIFTING GENERATES THE ESCHERICHIA-COLI DNA POLYMERASE-III GAMMA SUBUNIT FROM WITHIN THE GAMMA-SUBUNIT READING FRAME
PROGRAMMED RIBOSOMAL FRAMESHIFTING GENERATES THE ESCHERICHIA-COLI DNA POLYMERASE-III GAMMA SUBUNIT FROM WITHIN THE GAMMA-SUBUNIT READING FRAME
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DOI：
10.1093/nar/18.7.1725
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发表时间：
1990-04-11
影响因子：
14.9
通讯作者：
WALKER, JR
中科院分区：
文献类型：
--
作者：
BLINKOWA, AL;WALKER, JR
大肠杆菌（Escherichia coli）dnaX基因编码tau蛋白。和γ在一个阅读框中的DNA聚合酶III全酶亚基。71.1 kDa.和较短的γ。共享N末端序列。位于密码子428-430处的潜在核糖体移码信号的突变，而不改变τ的氨基酸序列。产物，消除了γ的可检测合成。亚基，这表明阅读框在该序列和γ处移位。由位于信号下游3个核苷酸的-1框中的无义密码子终止。这似乎是第一个已知的移码情况，移码与-1框中的终止密码子一起沿着使用，以终止阅读框内的肽。[在密码子498-499处突变一种二元肽（lys-lys），在该位点，LacZ融合蛋白在体外被切割（1）对γ没有影响。体内形成，表明体外观察到的裂解不是γ的机制。体内形成。
The Escherichia coli dnaX gene encodes both the .tau. and .gamma. subunits of DNA polymerase III holoenzyme in one reading frame. The 71.1 kDa .tau. and the shorter .gamma. share N-terminal sequences. Mutagenesis of a potential ribosomal frameshift signal located at codons 428-430 without changing the amino acid sequence of the .tau. product, eliminated detectable synthesis of the .gamma. subunit, suggesting that the reading frame is shifted at that sequence and .gamma. is terminated by a nonsense codon located in the -1 frame 3 nucleotides downstream of the signal. This seems to be the first known cases of a frameshift which is used, along with the termination codon in the -1 frame, to terminate a peptide within a reading frame. [Mutagenesis of a dibasic peptide (lys-lys) at codons 498-499, the site at which a .tau.''-''LacZ fusion protein was cleaved in vitro (1) had no effect on .gamma. formation in vivo, suggesting that cleavage observed in vitro is not the mechanism of .gamma. formation in vivo.].