sentences:  The MLH1-MLH3 heterodimer is an endonuclease that makes single-strand breaks in supercoiled double-stranded DNA.MLH1-MLH3 binds specifically to Holliday junctions and may act as part of a larger complex to process Holliday junctions during meiosis.MLH1-MLH3 heterodimer (MutL gamma) together with EXO1 and Sgs1 (ortholog of Bloom syndrome helicase) define a joint molecule resolution pathway that produces the majority of crossovers in budding yeast and, by inference, in mammals.