Human RECQ1 helicase-driven DNA unwinding, annealing, and branch migration: Insights from DNA complex structures
Pike ACW., Gomathinayagam S., Swuec P., Berti M., Zhang Y., Schnecke C., Marino F., von Delft F., Renault L., Costa A., Gileadi O., Vindigni A.
Significance RecQ DNA helicases are critical enzymes for the maintenance of genome integrity. Here, we determined the first DNA complex structures, to our knowledge, of the human RECQ1 helicase. These structures provide new insight into the RecQ helicase mechanism of DNA tracking, strand separation, strand annealing, and Holliday junction (HJ) branch migration. We identified a surface region in the winged-helix domain of RECQ1 that is important for both dsDNA recognition and HJ resolution, and we used a combination of biochemical, analytical ultracentrifugation, and EM experiments to begin elucidating the molecular basis of the distinct HJ resolution activities of human RecQ helicases.