Important role in G1 events required for bud emergence and septin organization. Coordinates cell growth and cell division at G2/M, essential for efficient cytokinesis and for regulation of SWE1. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Present with 149 molecules/cell in log phase SD medium. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family.