Structural highlights
Publication Abstract from PubMed
Homeostatic regulation of G-quadruplexes (G4s), four-stranded structures that can form in guanine-rich nucleic acids, requires G4 unwinding helicases. The mechanisms that mediate G4 unwinding remain unknown. We report the structure of a bacterial RecQ DNA helicase bound to resolved G4 DNA. Unexpectedly, a guanine base from the unwound G4 is sequestered within a guanine-specific binding pocket. Disruption of the pocket in RecQ blocks G4 unwinding, but not G4 binding or duplex DNA unwinding, indicating its essential role in structure-specific G4 resolution. A novel guanine-flipping and sequestration model that may be applicable to other G4-resolving helicases emerges from these studies.
A guanine-flipping and sequestration mechanism for G-quadruplex unwinding by RecQ helicases.,Voter AF, Qiu Y, Tippana R, Myong S, Keck JL Nat Commun. 2018 Oct 10;9(1):4201. doi: 10.1038/s41467-018-06751-8. PMID:30305632[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Voter AF, Qiu Y, Tippana R, Myong S, Keck JL. A guanine-flipping and sequestration mechanism for G-quadruplex unwinding by RecQ helicases. Nat Commun. 2018 Oct 10;9(1):4201. doi: 10.1038/s41467-018-06751-8. PMID:30305632 doi:http://dx.doi.org/10.1038/s41467-018-06751-8
