2'-O-methylation stabilizes Piwi-associated small RNAs and ensures DNA elimination in Tetrahymena.

ABSTRACT: Small RNAs approximately 20-30 nucleotides (nt) in length regulate gene expression at the transcriptional and post-transcriptional levels. In the plant Arabidopsis, all small RNAs are 3'-terminal 2'-O-methylated by HEN1, whereas only a subset of small RNAs carry this modification in metazoans. This methylation is known to stabilize small RNAs, but its biological significance remains unclear. In the ciliated protozoan Tetrahymena thermophila, two classes of small RNAs have been identified: RNAs approximately 28-29 nt long (scnRNAs) that are expressed only during sexual reproduction, and constitutively expressed approximately 23-24 nt siRNAs. In this study, we demonstrate that scnRNAs, but not siRNAs, are 2'-O-methylated at their 3' ends. The Tetrahymena HEN1 homolog Hen1p is responsible for

SUBMITTER: Kurth HM 

PROVIDER: S-EPMC2661841 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature