DRB4 dsRBD1 drives dsRNA recognition in Arabidopsis thaliana tasi/siRNA pathway.

ABSTRACT: In Arabidopsis thaliana, endogenous trans-acting and exogenous siRNA pathways are initiated by the interaction of DRB4 with trigger dsRNA. Further, DCL4:DRB4 complex cleaves the dsRNA into 21 bp siRNA. Understanding molecular determinants and mechanistic details of dsRNA recognition by DRB4 is vital for inducing long-term RNAi-mediated gene regulation in plants. Here, we present solution structures of individual and concatenated DRB4 dsRBDs and demonstrate modes of dsRNA binding by employing NMR, ITC and site-specific mutagenesis. While both dsRBDs adopt the canonical α-β-β-β-α fold, key structural differences and ms-μs dynamics located at the RNA binding region were observed for dsRBD1. These features favor dsRBD1 to orient itself and make stronger tripartite contact with dsRNA, a feature

SUBMITTER: Chiliveri SC 

PROVIDER: S-EPMC5737894 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature