Meiotic Nuclear Divisions 1 (MND1)

The product of the MND1 gene associates with HOP2 to form a stable heterodimeric complex that binds DNA and stimulates the recombinase activity of RAD51 and DMC1. Both the MND1 and HOP2 genes are indispensable for meiotic recombination. Mnd1-null yeast cells arrested in meiotic prophase, with most double-strand breaks unrepaired. Synaptonemal complex formation was incomplete, and homolog pairing was severely reduced. Mnd1 localized to chromatin throughout meiotic prophase, and this localization required Hop2. Mnd1 localized to chromosomes even in mutants that failed to initiate meiotic recombination. Hop2 and Mnd1 proteins coimmunoprecipitated from meiotic cell extracts. HOP2 and MND1 work as a complex to promote meiotic chromosome pairing and double-strand break repair.