Serine/threonine protein kinase that is thought to function in regulating kinetochore activity and entry into meiosis. Could phosphorylate IME1. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts with TDA1. Present with 6990 molecules/cell in log phase SD medium. Belongs to the protein kinase superfamily. CMGC Ser/Thr protein kinase family. GSK-3 subfamily.