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

• DOI: 10.1371/journal.pgen.1006422
• Publication Date: 2016-11-21T13:47:11Z
• Authors: Ziwei Li; Shengpeng Wang; Jinping Cheng; Chuanbin Su; Songxiao Zhong; Qi Liu; Yuda Fang; Yao Yu; Hong Lv; Yun Zheng; Binglian Zheng
• Keywords: Small nucleolar RNA

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 embryo lethal, but mechanism underlying lethality remains unclear. Here we characterized a weak mutant allele DBR1 Arabidopsis, dbr1-2, showed that global increase lariat was unexpectedly accompanied genome-wide reduction miRNA accumulation. The dbr1-2 mutation had no effects on expression biogenesis genes or primary miRNAs (pri-miRNAs), association pri-miRNAs with DCL1/HYL1 dicing complex impaired. were associated vivo competitively inhibited binding HYL1 pri-miRNA. Consistent impacts biogenesis, over-expression reduced localized nuclear bodies, partially co-localize HYL1, DCL1 mis-localized dbr1-2. Together our findings nearly four hundred exist wild type these also associate vivo, thus propose RNAs, decoys, inhibit processing, suggesting hitherto unknown layer regulation biogenesis.