A SWI/SNF Chromatin-Remodeling Complex Acts in Noncoding RNA-Mediated Transcriptional Silencing

作者：Zhu Yongyou; Rowley M Jordan; Boehmdorfer Gudrun; Wierzbicki Andrzej T^*

来源：Molecular Cell, 2013, 49(2): 298-309.

DOI：10.1016/j.molcel.2012.11.011

RNA-mediated transcriptional silencing prevents deleterious effects of transposon activity and controls the expression of protein-coding genes. It involves long noncoding RNAs (lncRNAs). In Arabidopsis thaliana, some of those lncRNAs are produced by a specialized RNA Polymerase V (Pol V). The mechanism by which lncRNAs affect chromatin structure and mRNA production remains mostly unknown. Here we identify the SWI/SNF ATP-dependent nucleosome-remodeling complex as a component of the RNA-mediated transcriptional silencing pathway. We found that SWI3B, an essential subunit of the SWI/SNF complex, physically interacts with a lncRNA-binding protein, IDN2. SWI/SNF subunits contribute to lncRNA-mediated transcriptional silencing. Moreover, Pol V mediates stabilization of nucleosomes on silenced regions. We propose that Pol V-produced lncRNAs mediate transcriptional silencing by guiding the SWI/SNF complex and establishing positioned nucleosomes on specific genomic loci. We further propose that guiding ATP-dependent chromatin-remodeling complexes may be a more general function of lncRNAs.

• 出版日期2013-1-24