生物谷報(bào)道：翻譯阻遏引起基因沉默

       
        應(yīng)激性小RNAs型鏈球菌Hfq折疊,，通過堿基配對(duì)從而down-regulate 靶mRNAs的表達(dá),。這種小RNAs型的核糖核蛋白復(fù)合體包括Hfq 和RNase E兩部分,。sRNP(regulatory outcomes of the RNase E/Hfq/small RNA-containing ribonucleoprotein complex )調(diào)節(jié)靶mRNA的快速降解和翻譯阻遏,。帶著 sRNP介導(dǎo)的mRNA不穩(wěn)定對(duì)全靶基因沉默影響的探尋我們使用了無(wú)mRNA降解的菌株進(jìn)行實(shí)驗(yàn)，研究證明sRNP缺損時(shí)只偶然發(fā)生翻譯抑制,。所以我們得出結(jié)論：通過sRNP調(diào)節(jié)的翻譯阻遏影響基因沉默,。sRNP介導(dǎo)的mRNA降解的生理作用可能是去除了mRNAs翻譯不活躍的細(xì)胞，從而導(dǎo)致基因沉默。

原始出處：Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan Teppei Morita, Yukari Mochizuki, and Hiroji Aiba* .Translational repression is sufficient for gene silencing by bacterial small noncoding RNAs in the absence of mRNA destruction .Stress-induced Hfq-binding small RNAs of Escherichia coli, SgrS and RyhB, down-regulate the expression of target mRNAs through base-pairing. These small RNAs form ribonucleoprotein complexes with Hfq and RNase E. The regulatory outcomes of the RNase E/Hfq/small RNA-containing ribonucleoprotein complex (sRNP) are rapid degradation of target mRNAs and translational inhibition. Here, we ask to what extent the sRNP-mediated mRNA destabilization contributes to the overall silencing of target genes by using strains in which the rapid degradation of mRNA no longer occurs. We demonstrate that translational repression occurs in the absence of sRNP-mediated mRNA destabilization. We conclude that translational repression is sufficient for gene silencing by sRNP. One possible physiological role of mRNA degradation mediated by sRNP is to rid the cell of translationally inactive mRNAs, making gene silencing irreversible.

友情連接:Translational repression is sufficient for gene silencing by bacterial small noncoding RNAs in the absence of mRNA destruction