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

J Biol Chem. 2009 Apr 17;284(16):10296-300. doi: 10.1074/jbc.C900018200. Epub 2009 Feb 25.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Crystallography, X-Ray
  • DEAD-box RNA Helicases / chemistry*
  • DEAD-box RNA Helicases / genetics
  • DEAD-box RNA Helicases / metabolism
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • Nucleocytoplasmic Transport Proteins / chemistry*
  • Nucleocytoplasmic Transport Proteins / genetics
  • Nucleocytoplasmic Transport Proteins / metabolism
  • Protein Structure, Secondary*
  • Protein Structure, Tertiary

Substances

  • Nucleocytoplasmic Transport Proteins
  • DDX19B protein, human
  • DEAD-box RNA Helicases