title: The DbpA catalytic core unwinds double-helix substrates by directly loading on them.
abstract: DbpA is a DEAD-box RNA helicase implicated in the assembly of the large ribosomal subunit. Similar to all the members of the DEAD-box family, the DbpA protein has two N-terminal RecA-like domains, which perform the RNA unwinding. However, unlike other members of this family, the DbpA protein also possesses a structured C-terminal RNA-binding domain that mediates specific tethering of DbpA to hairpin 92 of the Escherichia coli 23S ribosomal RNA. Previous studies using model RNA molecules containing hairpin 92 show that the RNA molecules support the DbpA protein's double-helix unwinding activity, provided that the double helix has a 3' single-stranded region. The 3' single-stranded region was suggested to be the start site of the DbpA protein's catalytic unwinding activity. The data presented here demonstrate that the single-stranded region 3' of the double-helix substrate is not required for the DbpA protein's unwinding activity and the DbpA protein unwinds the double-helix substrates by directly loading on them.
authors.affiliation: Department of Chemistry, University of Central Florida, Orlando, Florida 32816, USA.
authors.forename: Jared J
authors.initials: JJ
authors.lastname: Childs
authors.affiliation: Department of Chemistry, University of Central Florida, Orlando, Florida 32816, USA.
authors.forename: Riley C
authors.initials: RC
authors.lastname: Gentry
authors.affiliation: Department of Chemistry, University of Central Florida, Orlando, Florida 32816, USA.
authors.forename: Anthony F T
authors.initials: AF
authors.lastname: Moore
authors.affiliation: Department of Chemistry, University of Central Florida, Orlando, Florida 32816, USA.
authors.forename: Eda
authors.initials: E
authors.lastname: Koculi
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D020134:Catalytic Domain; D053487:DEAD-box RNA Helicases / Q000737:chemistry / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D011092:Polyethylene Glycols / Q000737:chemistry; D012338:RNA, Ribosomal, 23S / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D029968:Escherichia coli Proteins; D012338:RNA, Ribosomal, 23S; D011092:Polyethylene Glycols; D000255:Adenosine Triphosphate; C065908:dbpA protein, E coli; D053487:DEAD-box RNA Helicases
keywords: DEAD-box protein; DbpA; RNA helicase; ribosome assembly; ribosome maturation factor