本期《Science》兩篇論文通過觀測部分小鼠基因組從DNA到RNA的轉(zhuǎn)錄,，為哺乳動(dòng)物基因組的復(fù)雜性提供了詳細(xì)的描述。這項(xiàng)研究旨在確定DNA到RNA轉(zhuǎn)錄的起始和終止位置,，它證實(shí)也擴(kuò)展了最近一些工作提出的轉(zhuǎn)錄過程具有高度變化性的觀點(diǎn),。這個(gè)大的國際研究組還找到了新的編碼蛋白和非編碼的轉(zhuǎn)錄物，并發(fā)現(xiàn)非編碼轉(zhuǎn)錄物比過去認(rèn)為的要多,。一篇相關(guān)的“觀點(diǎn)”文章的作者寫道,，“小鼠基因組中令人驚訝的62%被轉(zhuǎn)錄”，在研究人員找到的181000個(gè)獨(dú)立的RNA轉(zhuǎn)錄物中,，約一半為非編碼RNA。在制造RNA過程中,，從模板DNA轉(zhuǎn)錄的那鏈被稱為“有義鏈”,，另外那鏈被稱為“反義鏈”。兩篇新論文中的第二篇提出,，反義轉(zhuǎn)錄比過去的研究所估計(jì)的要常見得多,。這些研究人員報(bào)告說，70%以上的測繪出的RNA轉(zhuǎn)錄單元,，與來自DNA的相對應(yīng)鏈的轉(zhuǎn)錄物有某種程度的重復(fù),。
Science Magazine and its online Knowledge Environments weave through the multilayered world of RNA in a special collection of articles published with the 2 September 2005 issue. In Science, Review and Viewpoint articles cover the relationship between RNA structure and function, the emerging "big world" of small RNAs, noncoding RNAs, and other aspects of this remarkable molecule; also in the issue are eleven new research papers touching various aspects of RNA. In addition, an accompanying pull-out poster limns the role of small RNAs in gene silencing. Science's Signal Transduction Knowledge Environment presents articles and an animation further exploring the roles of RNA in genomic complexity and regulation of gene expression. And the Science of Aging Knowledge Environment looks at how RNA interference has affected aging research in a key model system, the worm.
Poster: RNA Silencing
A downloadable PDF version of the pull-out poster (sponsored by Ambion) featured in this special issue.
