Department of Molecular Biology, Umeå Centre for Microbial Research (UCMR), Umeå University, Umeå, Sweden.
Genes Dev. 2010 Jul 1;24(13):1345-50. doi: 10.1101/gad.576310.
In Escherichia coli, the major nucleoid protein H-NS limits transcription by acting as a repressor or transcriptional silencer, presumably by its ability to close the looped chromosome domains in the nucleoid through DNA-protein-DNA bridging. Here, we demonstrate the direct involvement of H-NS as a positive factor stimulating translation of the malT mRNA. In vitro studies showed that H-NS facilitates a repositioning of the 30S preinitiation complex on the malT mRNA. H-NS stimulation of translation depended on the AU-rich -35 to -40 region of the mRNA. Several additional examples were found demonstrating a novel function for H-NS in translation of genes with suboptimal ribosome-binding sequences.
在大肠杆菌中,主要的核蛋白 H-NS 通过充当阻遏物或转录沉默子来限制转录,这可能是通过其通过 DNA-蛋白质-DNA 桥接封闭核区中的环化染色体结构域的能力。在这里,我们证明了 H-NS 直接作为一个正因子参与刺激 malT mRNA 的翻译。体外研究表明,H-NS 有助于重新定位 30S 起始复合物在 malT mRNA 上的位置。H-NS 对翻译的刺激依赖于 mRNA 的富含 AU 的-35 到-40 区域。还发现了几个其他的例子,证明了 H-NS 在翻译核糖体结合序列不太理想的基因方面具有新的功能。