In cell biology, the centrosome is an organelle that serves as the main microtubule organizing center (MTOC) of the animal cell, as well as a regulator of cell-cycle progression. The centrosome provides structure for the cell. The centrosome is thought to have evolved only in the metazoan lineage of eukaryotic cells. Fungi and plants lack centrosomes and therefore use other structures to organize their microtubules. Although the centrosome has a key role in efficient mitosis in animal cells, it is not essential in certain fly and flatworm species.
Centrins, also known as caltractins, are a family of calcium-binding phosphoproteins found in the centrosome of eukaryotes. Centrins are small calcium binding proteins that are ubiquitous centrosome components. There are about 350 “signature” proteins that are unique to eukaryotic cells but have no significant homology to proteins in archaea and bacteria. They are a type of protein that is essential and present in almost all eukaryotic cells and are found in the centrioles and pericentriolar lattice. Human centrin genes are CETN1, CETN2 and CETN3.
Centrin-2 is a protein that in humans is encoded by the CETN2 gene. It belongs to the centrin family of proteins.
Ninein is a protein that in humans is encoded by the NIN gene.
Centrosome-associated protein 350 is a protein that in humans is encoded by the CEP350 gene.
Centriolin is a protein that in humans is encoded by the CNTRL gene. It was previously known as CEP110.
Centrosome-associated protein CEP250 is a protein that in humans is encoded by the CEP250 gene. This gene encodes a core centrosomal protein required for centriole-centriole cohesion during interphase of the cell cycle. The encoded protein dissociates from the centrosomes when parental centrioles separate at the beginning of mitosis. The protein associates with and is phosphorylated by NIMA-related kinase 2, which is also associated with the centrosome. Furthermore, CEP135 is also required for the centriolar localization of CEP250.
Tubulin gamma-2 chain is a protein that in humans is encoded by the TUBG2 gene.
Centrosomal protein 170kDa, also known as CEP170, is a protein that in humans is encoded by the CEP170 gene.
Centriolar coiled-coil protein of 110 kDa also known as centrosomal protein of 110 kDa or CP110 is a protein that in humans is encoded by the CCP110 gene. It is a cell cycle-dependent CDK substrate and regulates centrosome duplication. CP110 suppresses a cilia assembly program.
Gamma-tubulin complex component 3 is a protein that in humans is encoded by the TUBGCP3 gene. It is part of the gamma tubulin complex, which required for microtubule nucleation at the centrosome.
Centrin-1 is a protein that in humans is encoded by the CETN1 gene. It belongs to the centrin family of proteins.
Ninein-like protein is a protein that in humans is encoded by the NINL gene. It is part of the centrosome.
Centrosomal protein of 135 kDa is a protein that in humans is encoded by the CEP135 gene. It is part of the centrosome throughout the cell cycle, being distributed in the pericentriolar material. CEP135 is required for the centriolar localization of CEP250.
Rootletin also known as ciliary rootlet coiled-coil protein (CROCC) is a protein that in humans is encoded by the CROCC gene. Rootletin is a component of the ciliary rootlet, and, together with CEP68 and CEP250, is required for centrosome cohesion.
Centrosomal protein of 192 kDa, also known as Cep192, is a protein that in humans is encoded by the CEP192 gene. It is the homolog of the C. elegans and D. melanogaster gene SPD-2.
Centrosomal protein of 164 kDa, also known as CEP164, is a protein that in humans is encoded by the CEP164 gene. Its function appears two be twofold: CEP164 is required for primary cilium formation. Furthermore, it is an important component in the response to DNA damage by UV light.
Centrosomal protein of 76 kDa, also known as CEP76, is a protein that in humans is encoded by the CEP76 gene.
Centrosomal protein of 152 kDa, also known as Cep152, is a protein that in humans is encoded by the CEP152 gene. It is the ortholog of the Drosophila melanogaster gene asterless (asl) and both are required for centriole duplication.
Sfi1 homolog, spindle assembly associated (yeast) is a protein that in humans is encoded by the SFI1 gene. It localizes to the centriole, and its S. pombe ortholog has been shown to be involved in spindle pole body duplication. SFI1 forms a complex with centrin 2.
