文章基本信息

标题：Putative Arabidopsis THO/TREX mRNA export complex is involved in transgene and endogenous siRNA biosynthesis
本地全文：下载
作者：Nataliya E. Yelina ; Lisa M. Smith ; Alexandra M. E. Jones 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2010
卷号：107
期号：31
页码：13948-13953
DOI：10.1073/pnas.0911341107
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：RNA silencing in plants and some animals has a non-cell-autonomous effect due to an RNA signal that moves between cells or organs. To identify unique factors involved in this process, we analyzed a group of Arabidopsis mutants with defective spread of RNA silencing from a transgene expressed specifically in the phloem. These mutants accumulated reduced amounts of small interfering (si)RNA from the transgene locus and from endogenous loci TAS1, TAS2, and an inverted repeat locus IR71. The defect in TAS1 and TAS2 siRNA biogenesis is in the processing of a long siRNA precursor. We mapped the mutations to a gene encoding the Arabidopsis homolog of a protein, TEX1, which is involved in intracellular transport of RNA in animals. TEX1 is a component of the THO/TREX complex, and we show that the Arabidopsis TEX1 interacts with other predicted components of a THO/TREX complex. Correspondingly, we found at least two other components of the Arabidopsis THO core complex that are involved in RNA silencing. To reconcile the effect of these mutations on transgene and endogenous gene siRNA, we propose a mechanism in which THO/TREX processes or transports a long RNA molecule so that it can be a template for secondary siRNA production.
关键词：RNA silencing ; trans -acting siRNA ; miRNA ; inverted repeat DNA