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The DEXD/H-box RNA helicase DDX19 is regulated by an {alpha}-helical switch.

ABSTRACT: 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.

SUBMITTER: Collins R

PROVIDER: S-EPMC2667716 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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The DEXD/H-box RNA helicase DDX19 is regulated by an {alpha}-helical switch.

Collins Ruairi R Karlberg Tobias T Lehtiö Lari L Schütz Patrick P van den Berg Susanne S Dahlgren Lars-Göran LG Hammarström Martin M Weigelt Johan J Schüler Herwig H

The Journal of biological chemistry 20090225 16

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 c ...[more]

PMID: 19244245

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