6hys

Publication Abstract from PubMed

DHX8 is a crucial DEAH-box RNA helicase involved in splicing and required for the release of mature mRNA from the spliceosome. Here we report the biochemical characterization of full-length human DHX8 and the catalytically active helicase core DHX8Delta547, alongside crystal structures of DHX8Delta547 bound to ADP and a structure of DHX8Delta547 bound to poly(A)6 single-strand RNA. Our results reveal that DHX8 has an in vitro binding preference for adenine-rich RNA and that RNA binding triggers release of ADP through significant conformational flexibility in the conserved DEAH-, P-loop and hook-turn motifs. We demonstrate the importance of R620 and both the hook-turn and hook-loop regions for DHX8 helicase activity, and propose that the hook-turn acts as a gatekeeper to regulate directional movement of the 3' end of RNA through the RNA binding channel. This study provides an in-depth understanding of the activity of DHX8 and contributes insights into the RNA unwinding mechanisms of the DEAH-box helicase family.

Structural and functional characterisation of human RNA helicase DHX8 provides insights into the mechanism of RNA-stimulated ADP release.,Felisberto-Rodrigues C, Thomas JC, McAndrew C, Le Bihan YV, Burke R, Workman P, van Montfort RLM Biochem J. 2019 Aug 13. pii: BCJ20190383. doi: 10.1042/BCJ20190383. PMID:31409651^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.