In eukaryotic cells, upon ATP binding, recombinase RAD51 promoters assemble into a right-handed helical filament on ssDNA (the invading strand) called the presynaptic filament. We carried out cryo-EM analyses of human RAD51 in different stages of the DNA strand exchange process and determined the structures of presynaptic and postsynaptic complexes of RAD51 at near atomic resolution as well as an intermediate state of the synaptic complex where DNA strand exchange becomes arrested upon encountering a heterologous region.
Xu J, Zhao L, Xu Y, Zhao W, Sung P*, Wang HW*. (2017) Cryo-EM structures of human RAD51 recombinase filaments during catalysis of DNA-strand exchange. Nat. Struct. Mol. Biol., 24(1):40-46. (*co-corresponding authors)