RNAi是大部分生物遺傳控制網(wǎng)絡(luò)中的一個(gè)主要的通路,。最近研究人員在一種芽殖酵母Saccharomyces castellii中發(fā)現(xiàn)了該過程，Saccharomyces castellii與啤酒酵母（S. cerevisiae）是近親,，是百念珠菌（Candida albicans）中一種常見的人類病原體,。
芽殖酵母常常作為很多復(fù)雜生物的研究模型,，在工業(yè)上用于生產(chǎn)啤酒和生物燃料，在醫(yī)藥產(chǎn)業(yè)用于生產(chǎn)藥物和疫苗,。研究酵母的RNAi能力,，以及使用RNAi改變酵母蛋白的產(chǎn)量可能對所有相關(guān)產(chǎn)業(yè)來說都是有益的。
據(jù)研究人員Kathleen Xie介紹,，在很長的一段時(shí)間內(nèi),，人們認(rèn)為酵母根本沒有RNAi，因?yàn)槠【平湍甘茄恐辰湍傅哪Ｐ?，其沒有RNAi,。還有一點(diǎn)比較遺憾，一直沒有一個(gè)芽殖酵母的模式生物可用于RNAi研究,。
由于酵母基因組易于操作,，而且酵母細(xì)胞有很高的繁殖率，此外還有許多和人類細(xì)胞一樣的功能和生化通路,，所以酵母是一個(gè)很好的模型,，可用于很多復(fù)雜生物細(xì)胞的研究。
研究人員發(fā)現(xiàn),，在很多復(fù)雜的生物中都存在RNAi通路,，植物和很多動(dòng)物用RNAi沉默病毒和轉(zhuǎn)座子的基因。在芽殖酵母RNAi中有兩個(gè)主要的蛋白,，即Dicer和Argonaute,，這是在啤酒酵母中沒有的。此外,，還發(fā)現(xiàn)其他的芽殖酵母中也有Argonaute,，表明其可能參與RNAi。
結(jié)果表明,，酵母的Dicer蛋白,，看起來與動(dòng)物，植物和其他真菌的Dicer蛋白非常不同,。芽殖酵母Dicer蛋白的這種不同這可能有助于解釋RNAi長期未在這些物種中發(fā)現(xiàn)的原因,。
隨著S. castellii的Dicer蛋白的證實(shí)以及S. cerevisiae中RNAi通路的重建 ，科研人員現(xiàn)在幾乎可以使用所有可行的工具來研究芽殖酵母中的RNAi通路,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science DOI: 10.1126/science.1176945
RNAi in Budding Yeast
Ines A. Drinnenberg 1, David E. Weinberg 2, Kathleen T. Xie 2, Jeffrey P. Mower 3, Kenneth H. Wolfe 4, Gerald R. Fink 5, David P. Bartel 2*
1 Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA.; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
2 Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA.; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
3 Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.; Present address: Center for Plant Science Innovation and Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68588, USA.
4 Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.
5 Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA.; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
RNA interference (RNAi), a gene-silencing pathway triggered by double-stranded RNA, is conserved in diverse eukaryotic species but has been lost in the model budding yeast, Saccharomyces cerevisiae. Here, we show that RNAi is present in other budding-yeast species, including Saccharomyces castellii and Candida albicans. These species use noncanonical Dicer proteins to generate small interfering RNAs, which mostly correspond to transposable elements and Y' subtelomeric repeats. In S. castellii, RNAi mutants are viable but have excess Y' mRNA levels. In S. cerevisiae, introducing Dicer and Argonaute of S. castellii restores RNAi, and the reconstituted pathway silences endogenous retrotransposons. These results identify a novel class of Dicer proteins, bring the tool of RNAi to the study of budding yeasts, and bring the tools of budding yeast to the study of RNAi.
