Sister Chromatid Cohesion Remodeling and Meiotic Recombination

Proper control of cohesion along the chromosome arms is essential for segregation of homologous chromosomes in meiosis. In a recent study we reported that Tid1p, a protein previously implicated in recombination, is required for resolution of Mcd1p-dependent cohesion in meiosis. Here we demonstrate that Pds5p and Dmc1p promote this cohesion. Pds5p is known to be required for maintenance of cohesion while Dmc1p is recognized as essential for meiotic recombination. Finding that the same defect in separation of sister chromatids could be suppressed by disrupting the functions of these proteins supports the emerging recognition that cohesion is remodeled during recombination and further indicates that cohesion is modified specifically to regulate meiotic recombination. We also find that overexpression of the regulatory subunit of Cdc7p kinase, Dbf4p, suppresses the tid1Δ sporulation defect, suggesting a role for Cdc7p/Dbf4p in regulating cohesion.