Single-strand annealing protein involved in recombinational repair; binds to and catalyzes the annealing of single-stranded mtDNA pre-complexed with Rim1p, a ssDNA-binding protein; also involved in interstrand cross-link repair; oligomerizes to form rings and filaments; shares functionally conserved sequence signatures with Rad52p; component of the mitochondrial nucleoid, required for repair of oxidative mtDNA damage and mitochondrial genome maintenance