Virus infection triggers widespread silencing of host genes by a distinct class of endogenous siRNAs in Arabidopsis.

ABSTRACT: Antiviral immunity controlled by RNA interference (RNAi) in plants and animals is thought to specifically target only viral RNAs by the virus-derived small interfering RNAs (siRNAs). Here we show that activation of antiviral RNAi in Arabidopsis plants is accompanied by the production of an abundant class of endogenous siRNAs mapped to the exon regions of more than 1,000 host genes and rRNA. These virus-activated siRNAs (vasiRNAs) are predominantly 21 nucleotides long with an approximately equal ratio of sense and antisense strands. Genetically, vasiRNAs are distinct from the known plant endogenous siRNAs characterized to date and instead resemble viral siRNAs by requiring Dicer-like 4 and RNA-dependent RNA polymerase 1 (RDR1) for biogenesis. However, loss of exoribonuclease4/thylene-insens

SUBMITTER: Cao M 

PROVIDER: S-EPMC4209997 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature