[Trans-acting short interfering RNAs].
RNA is now considered a key factor in the regulation of gene expression. There are several classes of small regulatory RNAs in plants, functioning in posttranscriptional gene silencing (PTGS) or epigenetic DNA modification. Trans-acting short interfering RNAs (tasiRNAs) form a class of small regulatory RNAs which has been distinguished only recently. To date, five genes encoding tasiRNAs have been identified in Arabidopsis thaliana. TasiRNAs derive from non-coding RNA precursors which are initially targeted for cleavage by a miRNA. Cleavage products are then converted into dsRNAs by a RNA dependent RNA polymerase and sequentially cleaved into 21-nt tasiRNAs. Like the majority of plant miRNAs, tasiRNAs regulate gene expression at the posttranscriptional level, guiding cleavage of ARF and PPR transcripts. Here, we briefly present tasiRNAs and speculate whether they form a homogeneous class of siRNAs.
Warkocki
Zbigniew
Z
Faculty of Biology, Adam Mickiewicz University, Poznań, Poland.
Figlerowicz
Marek
M
D020869:Gene Expression Profiling / Q000379:methods; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D035683:MicroRNAs / Q000235:genetics*; D010944:Plants / Q000235:genetics; D034622:RNA Interference / Q000502:physiology; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics*; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics; D034743:RNA-Induced Silencing Complex / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
D035683:MicroRNAs; D018749:RNA, Plant; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex; D015534:Trans-Activators; D012324:RNA-Dependent RNA Polymerase