PMID: 19244245
Collins R, Karlberg T, Lehtio L, Schutz P, van den Berg S, Dahlgren LG, Hammarstrom M, Weigelt J, Schuler H
The DEXD/H-box RNA helicase DDX19 is regulated by an {alpha}-helical switch.
J Biol Chem. 2009 Apr 17;284(16):10296-300. Epub 2009 Feb 25.
DEXD/H-box RNA helicases couple ATP hydrolysis to RNA remodeling by an unknown mechanism. We used x-ray crystallography and biochemical analysis of the human DEXD/H-box protein DDX19 to investigate its regulatory mechanism. The crystal structures of DDX19, in its RNA-bound prehydrolysis and free posthydrolysis state, reveal an alpha-helix that inserts between the conserved domains of the free protein to negatively regulate ATPase activity. This finding was corroborated by biochemical data that confirm an autoregulatory function of the N-terminal region of the protein. This is the first study describing crystal structures of a DEXD/H-box protein in its open and closed cleft conformations.