Abstract
We are studying RNA-mediated transcriptional gene silencing to understand effects of siRNA on various chromatin in rice. RNA-mediated TGS is a chromatin-based gene silencing, triggered by siRNA containing sequences that are identical to the promoter. We chose a total of 8 target genes and produced transgenic rice that accumulated siRNA containing sequences of target promoter. Our results indicated that 35S::GFP and Se5 were silenced, but the other 6 target genes were not silenced. Furthermore, we investigated the correlation between the silencing and epigenetic modifications. DNA methylation analysis showed that all 8 target promoters were methylated. ChIP analysis indicated that histone H3 deacetylation was observed in only the 35S target promoter, which was silenced. Now, we are analyzing the Se5 target promoter, which was silenced, for histone modifications. We also investigate the effects of DNA methylation or histone deacetylation inhibitors on RNA-mediated TGS. The epigenetic function of siRNA will be discussed.
