tmRNA-induced release of messenger RNA from stalled ribosomes
tmRNA-induced release of messenger RNA from stalled ribosomes
复制标题
DOI：
10.1016/j.jmb.2005.05.033
复制
发表时间：
2005-07-29
影响因子：
5.6
通讯作者：
Ehrenberg, M
中科院分区：
文献类型：
--
作者：
Ivanova, N;Pavlov, MY;Ehrenberg, M
真细菌细胞中截短mRNA上的核糖体可以通过称为反式翻译的过程被tmRNA拯救。我们在这里证明，从停滞的核糖体中释放截短的mRNA加速显着后trans-peptidation后，tmRNA结合到核糖体。然而，截短的mRNA的快速释放需要EF-G依赖性的肽基-tmRNA从核糖体的A位点移位到P位点。我们还表明，肽基-tRNA易位前后的mRNA释放速率与脱酰tRNA的解离速率相关，表明mRNA主要通过密码子：反密码子与tRNA的相互作用保留在核糖体上。对于在截短位点附近具有强Shine-Dalgarno（SD）样序列的mRNA以及对于在P位点密码子下游具有长3'延伸的mRNA，mRNA释放速率降低。在前一种情况下，释放速率降低是由于mRNA和核糖体之间持续的SD-抗SD相互作用。(c)2005爱思唯尔有限公司保留所有权利。
A ribosome stalled on a truncated mRNA in the eubacterial cell can be rescued by tmRNA via a process called trans-translation. We demonstrate here that release of truncated mRNAs from stalled ribosomes accelerates significantly already after trans-peptidation following tmRNA binding to the ribosome. However, rapid release of truncated mRNA requires EF-G-dependent translocation of peptidyl-tmRNA from the A to the P site of the ribosome. We show also that the rate of mRNA release before and after peptidyl-tmRNA translocation correlates well with the rate of dissociation of deacylated tRNA, indicating that mRNA is retained on the ribosome mainly through codon:anticodon interaction with tRNA. The rate of mRNA release is reduced for mRNAs with strong Shine-Dalgarno (SD)-like sequences in the vicinity of the truncation site as well as for mRNAs with long 3' extensions downstream from the P-site codon. The reduced rate of release in the former case was due to a persisting SD-anti SD interaction between mRNA and the ribosome. (c) 2005 Elsevier Ltd. All rights reserved.