摘要
RNA沉默(RNA silencing)是真核生物中的一种抵抗外源遗传因子(病毒、转座子或转基因)及调控基因表达的防御机制。参与植物RNA沉默的酶及蛋白质主要包括6种RNA依赖的RNA聚合酶、4种Dicer-like(DCL)核酸内切酶和10种Argonautes蛋白。植物中4条RNA沉默途径分别由微小RNA (miRNAs)和3种小干扰RNA(siRNAs)介导,包括反式作用siRNAs(ta-siRNAs)、天然反义siRNAs(nat- siRNAs)和异染色质siRNAs(hc-siRNAs)。在植物RNA沉默的系统性传播中,由DCL4或DCL2将dsRNAs裁剪为次级siRNAs,以放大RNA沉默信号和增强沉默效应。
RNA silencing is a defense mechanism in eukaryotes which can resist the exogenous genetic factors (virus, transposon or transgene) and regulate gene expression. It was found that many important enzymes and proteins are involved in the RNA silencing of plants, including 6 kinds of RNA-dependent RNA polymerases, 4 types of Dicer-like (DCL) endoribonucleases and 10 kinds of argonantes protein. In plants, four RNA silencing pathways are directed by rnicroRNAs (miRNAs) and three types of small interfering RNAs (siRNAs) which are trans-acting siRNAs (ta-siRNAs), natural antisense siRNAs (nat-siRNAs) and heterochromatin siRNAs (hc- siRNAs). In the systematic RNA silencing, DCL4 or/and DCL2 process dsRNAs into the secondary siRNAs to amplify silencing signals and effects.
出处
《生命科学》
CSCD
2008年第5期784-789,共6页
Chinese Bulletin of Life Sciences
基金
国家自然科学基金项目(30500300)
教育部新世纪优秀人才支持计划(NCET-06-0558)资助项目
教育部留学回国人员科研启动基金
安徽省优秀青年科技基金(06043089)
安徽省教育厅自然科学研究重点项目(NO.2006KJ061A)