翻訳と辞書 |
5 prime ureB sRNA : ウィキペディア英語版 | 5 prime ureB sRNA
In molecular biology, 5' ureB sRNA is a small RNA. It is located at the 5' end of the ureB gene in the urease gene cluster, and is antisense to ureB. Its expression is regulated by the arsS/arsR two-component regulatory system, arsS downregulates 5' ureB sRNA expression under acidic conditions leading to an increase in ureB expression. 5' ureB sRNA suppresses transcription of ureA and ureB by base-pairing with ureAB mRNA resulting in premature termination of the transcript to the 5' of ureB. ==Abstract==
Urease is an essential component of gastric acid acclimation by Helicobacter pylori. The increased level of urease in gastric acidity is due, in part, to acid activation of the two-component system consisting of the membrane sensor HP0165 (ArsS) and its response regulator HP0166 (ArsR), which regulates transcription of the seven genes in two separate operons (ureAB and ureIEFGH) of the urease gene cluster. Recently, we identified a novel cis-encoded antisense small RNA, 5'ureB-sRNA, targeted at the 5' end of ureB, which downregulates ureAB expression by truncation of the ureAB transcript at neutral pH. It is not known whether the truncated transcript is due to transcription termination or processing of the full-length mRNA by codegradation of a ureAB mRNA-sRNA hybrid complex. S1 nuclease mapping assays show that the truncated transcript is due to transcription termination. Further studies using an in vitro transcription assay found that 5'ureB-sRNA promotes premature termination of transcription of ureAB mRNA. These results suggest that the antisense small RNA 5'ureB-sRNA downregulates ureAB expression by enhancing transcription termination 5' of ureB. With this mechanism, a limited amount of 5'ureB-sRNA is sufficient to regulate the relatively high level of ureAB transcript.〔(http://www.ncbi.nlm.nih.gov/ ) Wen Y, Feng J, SachsG.〕
抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「5 prime ureB sRNA」の詳細全文を読む
スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|