Regulated Proteolysis of MutS? Controls Meiotic Crossing Over (Molecular Cell)

He et al. show that regulated proteolysis is a key determinant of crossing over during meiosis. Recombination factor MutS? (Msh4-Msh5) is regulated by a degron that directly targets Msh4 for ubiquitin-independent proteasomal proteolysis. Degron phosphorylation by Dbf4-depenent kinase Cdc7 attenuates the Msh4 degron to activate the crossover function of MutS?.