López-Perrote, AndresHug, NeleGonzález-Corpas, AnaRodríguez, Carlos FSerna, MarinaGarcía-Martín, CarmenCaceres, Javier FLlorca, OscarBoskovic, JasminkaFernandez-Leiro, RafaelLlorca Blanco, Oscar AntonioLópez-Perrote, AndresHug, NeleGonzález-Corpas, AnaRodríguez, Carlos FGarcía-Martín, CarmenCaceres, Javier FLlorca, OscarFernandez-Leiro, Rafael2021-03-312021-03-312020-11-18Elife. 2020 ;9:e63042.http://hdl.handle.net/20.500.12105/12498Nonsense-mediated mRNA decay (NMD) is a surveillance pathway that degrades aberrant mRNAs and also regulates the expression of a wide range of physiological transcripts. RUVBL1 and RUVBL2 AAA-ATPases form an hetero-hexameric ring that is part of several macromolecular complexes such as INO80, SWR1, and R2TP. Interestingly, RUVBL1-RUVBL2 ATPase activity is required for NMD activation by an unknown mechanism. Here, we show that DHX34, an RNA helicase regulating NMD initiation, directly interacts with RUVBL1-RUVBL2 in vitro and in cells. Cryo-EM reveals that DHX34 induces extensive changes in the N-termini of every RUVBL2 subunit in the complex, stabilizing a conformation that does not bind nucleotide and thereby down-regulates ATP hydrolysis of the complex. Using ATPase-deficient mutants, we find that DHX34 acts exclusively on the RUVBL2 subunits. We propose a model, where DHX34 acts to couple RUVBL1-RUVBL2 ATPase activity to the assembly of factors required to initiate the NMD response.engVoRhttp://creativecommons.org/licenses/by-nc-sa/4.0/Cryoelectron MicroscopyATPases Associated with Diverse Cellular ActivitiesCarrier ProteinsCloning, MolecularDNA HelicasesGene Expression Regulation, EnzymologicHEK293 CellsHumansRNA HelicasesAtribución-NoComercial-CompartirIgual 4.0 Internacional33205750910.7554/eLife.630422050-084XeLifeopen access