6qv3

Publication Abstract from PubMed

RNA-dependent NTPases can act as RNA/RNA-protein remodeling enzymes and typically exhibit low NTPase activity in the absence of RNA/RNA-protein substrates. How futile intrinsic NTP hydrolysis is prevented is frequently not known. The ATPase/RNA helicase Brr2 belongs to the Ski2-like family of nucleic acid-dependent NTPases and is an integral component of the spliceosome. Comprehensive nucleotide binding and hydrolysis studies are not available for a member of the Ski2-like family. We present crystal structures of Chaetomium thermophilum Brr2 in the apo, ADP-bound, and ATPgammaS-bound states, revealing nucleotide-induced conformational changes and a hitherto unknown ATPgammaS binding mode. Our results in conjunction with Brr2 structures in other molecular contexts reveal multiple molecular mechanisms that contribute to the inhibition of intrinsic ATPase activity, including an N-terminal region that restrains the RecA-like domains in an open conformation and exclusion of an attacking water molecule, and suggest how RNA substrate binding can lead to ATPase stimulation.

Molecular Mechanism Underlying Inhibition of Intrinsic ATPase Activity in a Ski2-like RNA Helicase.,Absmeier E, Santos KF, Wahl MC Structure. 2020 Feb 4;28(2):236-243.e3. doi: 10.1016/j.str.2019.11.014. Epub 2019, Dec 16. PMID:31859026^[1]

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