FANCA promotes strand exchange. Titration of the purified FANCA-WT and F1263Δ mutant (10, 20, 30, and 40 nM calculated as monomers) on (A) a pre-annealed splayed arm structure (Right panel, quantification of the SE activity; Experiments were independently repeated 3 times; Error bar, standard deviation); (B) a dsDNA structure with partial 5′-end resection of one strand and a short blunt-ended dsDNA with full homology to the uncovered flap of the invading DNA structure; and (C) a dsDNA structure with partial 3′-end resection of one strand and a short blunt-ended dsDNA with full homology to the uncovered flap of the invading DNA structure. Quantification of SE activity is represented by % product below each gel. (D) Titration of the purified FANCA-WT, FANCA-F1263Δ mutant, and RAD52 (10, 20, 30, 40, and 50 nM) in a D-loop formation assay. Red asterisks (*) indicate 32P labeling.