Intron Lariat RNA Inhibits MicroRNA Biogenesis by Sequestering the Dicing Complex in Arabidopsis.

ABSTRACT: Lariat RNAs formed as by-products of splicing are quickly degraded by the RNA debranching enzyme 1 (DBR1), leading to their turnover. Null dbr1 mutants in both animals and plants are embryo lethal, but the mechanism underlying the lethality remains unclear. Here we characterized a weak mutant allele of DBR1 in Arabidopsis, dbr1-2, and showed that a global increase in lariat RNAs was unexpectedly accompanied by a genome-wide reduction in miRNA accumulation. The dbr1-2 mutation had no effects on expression of miRNA biogenesis genes or primary miRNAs (pri-miRNAs), but the association of pri-miRNAs with the DCL1/HYL1 dicing complex was impaired. Lariat RNAs were associated with the DCL1/HYL1 dicing complex in vivo and competitively inhibited the binding of HYL1 with pri-miRNA. Consistent with

SUBMITTER: Li Z 

PROVIDER: S-EPMC5147768 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature