Serine/threonine-protein kinase. Needed for the initiation of DNA synthesis during mitosis as well as for synaptonemal complex formation and commitment to recombination during meiosis. Required for HTA1-HTB1 locus transcription repression. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Associates with DBF4 and ORC2. Present with 1600 molecules/cell in log phase SD medium. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. CDC7 subfamily.