Synaptonemal complex SUMOylation is maintained by Nup60-dependent docking of Ulp1 at the nuclear periphery

The nuclear pore complex (NPC) basket has been implicated in regulating meiotic recombination, but the underlying mechanism remained elusive. Here, we show that most basket subunits are required for controlled crossing-over in budding yeast. Central to this function, the nucleoporin Nup60 anchors the SUMO protease Ulp1 at the nuclear periphery, thereby protecting the synaptonemal complex (SC) protein Ecm11 from premature deSUMOylation. Unscheduled dissociation of Ulp1 from the NPC impairs Ecm11 SUMOylation, disrupts synapsis, elevates crossovers, and compromises gamete viability. Remarkably, engineered tethering of Ulp1 to the NPC restores SC integrity and recombination control in basket mutants. We further show that Polo-like kinase Cdc5 remodels SUMO homeostasis at the prophase I-metaphase I transition, triggering partial Ulp1 release from the NPC and phosphorylating the SUMO ligases Siz1 and Siz2. These findings uncover how nucleoporins, SUMO enzymes, and kinase signaling cooperate to coordinate SC dynamics with crossover control, safeguarding meiotic genome transmission.