Condron B G, Gesteland R F, Atkins J F
Department of Human Genetics, University of Utah, Salt Lake City 84112.
Nucleic Acids Res. 1991 Oct 25;19(20):5607-12. doi: 10.1093/nar/19.20.5607.
The signals necessary for the translational frameshift in the gene 10 message of bacteriophage T7 include the previously identified frameshift site and the 3' non-coding region, over 200 bases downstream. The functional components of the frameshift site are identified in this study and show that the site most probably operates by the retroviral type two site mechanism. However, the base pairing requirements for the first tRNA are much more relaxed after the slip than is seen in other examples. The element at the 3' end of the gene, also necessary for frameshifting, is examined but only the extreme 5' side of the transcriptional terminator stem-loop structure in the 3' non-coding region seems to be required. No simple secondary structural model can explain the involvement of this sequence. The T7 frameshift site can be replaced with either a T3 site or a E. coli dnaX site. Both show higher levels of frameshifting than with the T7 site.
噬菌体T7基因10信息中翻译移码所需的信号包括先前确定的移码位点和下游200多个碱基的3'非编码区。本研究确定了移码位点的功能成分，表明该位点很可能通过逆转录病毒II型位点机制发挥作用。然而，与其他例子相比，第一个tRNA滑动后的碱基配对要求要宽松得多。对基因3'端的元件（移码也需要该元件）进行了研究，但似乎只需要3'非编码区转录终止子茎环结构的最5'端。没有简单的二级结构模型可以解释该序列的作用。T7移码位点可以被T3位点或大肠杆菌dnaX位点取代。两者都比T7位点表现出更高水平的移码。
