Exit from mitosis is triggered by Tem1-dependent release of the protein phosphatase Cdc14 from nucleolar RENT complex

Exit from mitosis in budding yeast requires a group of essential proteins-i ncluding the GTPase Tem1 and the protein phosphatase Cdc14-that downregulat e cyclin-dependent kinase activity. We identified a mutation, net1-1, that bypasses the lethality of tem 1 Delta. NEM encodes a novel protein, and mas s spectrometric analysis reveals that it is a key component of a multifunct ional complex, denoted RENT (for regulator of nucleolar silencing and telop hase), that also contains Cdc14 and the silencing regulator Sir2. From G1 t hrough anaphase, RENT localizes to the nucleolus, and Cdc14 activity is inh ibited by Net1. In late anaphase, Cdc14 dissociates from RENT, disperses th roughout the cell in a Tem1-dependent manner, and ultimately triggers mitot ic exit. Nucleolar sequestration may be a general mechanism for the regulat ion of diverse biological processes.