Cyclin-dependent kinase inhibitor rum1
Schizosaccharomyces pombe (strain 972 / ATCC 24843)
Regulator of cell cycle G1 phase progression. Ensures the correct sequence of S phase and mitosis in the cell by acting as an inhibitor of the cdc2 mitotic kinase. Probably interacts with cdc2 to inhibit its action until the cell mass for Start is reached. Determines the length of the pre-Start G1 period and prevents mitosis from happening in early G1 cells. Required for maintaining pheromone-induced G1 arrest. Acts as an adapter protein since interaction with cdc13 promotes cyclin proteolysis during G1. Becomes a target for degradation at the G1/S phase transition, following phosphorylation by cig1-associated cdc2 at the G1/S phase transition.