PLK4
Domain
Cryptic POLO box 1 (CPB1) and Cryptic POLO box 2 (CPB2) domains can simultaneously bind to both TENT5C and CEP192.
Function
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. Required for the recruitment of STIL to the centriole and for STIL-mediated centriole amplification (PubMed:22020124). Phosphorylates CEP131 at 'Ser-78' and PCM1 at 'Ser-372' which is essential for proper organization and integrity of centriolar satellites (PubMed:30804208).
Involvement in disease
Microcephaly and chorioretinopathy, autosomal recessive, 2
MCCRP2
A severe disorder characterized by microcephaly, delayed psychomotor development, growth retardation with dwarfism, and ocular abnormalities.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
Acetylation by KAT2A and KAT2B impairs kinase activity by shifting the kinase to an inactive conformation.
Ubiquitinated; leading to its degradation by the proteasome (By similarity). Deubiquitinated by USP54; leading to PLK4 stabilization (PubMed:36590171).
Tyrosine-phosphorylated by TEC.
Sequence Similarities
Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. CDC5/Polo subfamily.
Cellular localization
- Cytoplasm
- Cytoskeleton
- Microtubule organizing center
- Centrosome
- Centriole
- Nucleus
- Nucleolus
- Cleavage furrow
- Cytoplasm
- Cytoskeleton
- Microtubule organizing center
- Centrosome
- Component of the deuterosome, a structure that promotes de novo centriole amplification in multiciliated cells that can generate more than 100 centrioles. Associates with centrioles throughout the cell cycle. According to PubMed:16244668, it is not present at cleavage furrows.
Alternative names
SAK, STK18, PLK4, Serine/threonine-protein kinase PLK4, Polo-like kinase 4, Serine/threonine-protein kinase 18, Serine/threonine-protein kinase Sak, PLK-4