title: Comparisons between the structures of HCV and Rep helicases reveal structural similarities between SF1 and SF2 super-families of helicases.
abstract: Three helicase structures have been determined recently: that of the DNA helicase PcrA, that of the hepatitis C virus RNA helicase, and that of the Escherichia coli DNA helicase Rep. PcrA and Rep belong to the same super-family of helicases (SF1) and are structurally very similar. In contrast, the HCV helicase belongs to a different super-family of helicases, SF2, and shows little sequence homology with the PcrA/Rep helicases. Yet, the HCV helicase is structurally similar to Rep/PcrA, suggesting preservation of structural scaffolds and relationships between helicase motifs across these two super-families. The comparison study presented here also reveals the existence of a new helicase motif in the SF1 family of helicases.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: S
authors.initials: S
authors.lastname: Korolev
authors.forename: N
authors.initials: N
authors.lastname: Yao
authors.forename: T M
authors.initials: TM
authors.lastname: Lohman
authors.forename: P C
authors.initials: PC
authors.lastname: Weber
authors.forename: G
authors.initials: G
authors.lastname: Waksman
mesh_terms: D000595:Amino Acid Sequence; D004265:DNA Helicases / Q000648:ultrastructure*; D004268:DNA-Binding Proteins; D004926:Escherichia coli / Q000201:enzymology; D016174:Hepacivirus / Q000201:enzymology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D020365:RNA Helicases; D012316:RNA Nucleotidyltransferases / Q000648:ultrastructure*; D016415:Sequence Alignment; D015534:Trans-Activators / Q000648:ultrastructure*; D017361:Viral Nonstructural Proteins / Q000648:ultrastructure*; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases
chemical_list: D004265:DNA Helicases; D004268:DNA-Binding Proteins; D020365:RNA Helicases; D012316:RNA Nucleotidyltransferases; D015534:Trans-Activators; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C045264:replication initiator protein