Serine/threonine-protein kinase that plays a central role in centriole duplication. Able to trigger procentriole formation on the surface of the parental centriole cylinder; leading to the recruitment of centriole biogenesis proteins such as SASS6; CENPJ/CPAP; CCP110; CEP135 and gamma-tubulin. When overexpressed; it is able to induce centrosome amplification through the simultaneous generation of multiple procentrioles adjoining each parental centriole during S phase. Phosphorylates 'Ser-151' of FBXW5 during the G1/S transition; leading to inhibit FBXW5 ability to ubiquitinate SASS6. Its central role in centriole replication suggests a possible role in tumorigenesis; centrosome aberrations being frequently observed in tumors. Also involved in deuterosome-mediated centriole amplification in multiciliated that can generate more than 100 centrioles. Also involved in trophoblast differentiation by phosphorylating HAND1; leading to disrupt the interaction between HAND1 and MDFIC and activate HAND1. Phosphorylates CDC25C and CHEK2. {ECO:0000269|PubMed:16244668; ECO:0000269|PubMed:16326102; ECO:0000269|PubMed:17681131; ECO:0000269|PubMed:18239451; ECO:0000269|PubMed:19164942; ECO:0000269|PubMed:21725316}.