centrin2

Centrin-2, also known as CETN2, is a small calcium-binding protein of the centrin family found in the centrosome and basal bodies of cilia in many eukaryotic cells, including humans. It is encoded by the CETN2 gene and belongs to the EF-hand superfamily, with motifs that bind calcium and regulate its interactions with other centrosomal components.

Localization of centrin-2 is primarily at the centrioles and basal bodies, and it is associated with centrosomes throughout the cell cycle. Its presence at spindle poles during mitosis links it to centrosome function and microtubule organization. Centrin-2 is considered a structural and regulatory component of the centrosome–cilium apparatus.

Functions attributed to centrin-2 include participation in centrosome duplication and maturation, maintenance of spindle pole integrity, and support for ciliogenesis through its role at basal bodies. Calcium binding modulates centrin-2’s conformation, influencing its binding to other centrosomal and cytoskeletal proteins, and thereby affecting centrosome dynamics and microtubule nucleation.

Interactions and regulation of centrin-2 involve a network of centrosomal proteins and structural partners; in experimental systems, reduced centrin-2 levels can impair centriole duplication and ciliogenesis, with potential consequences for cell division fidelity and genome stability. Its conserved presence across eukaryotes reflects a fundamental role in the coordination of centrosome and cilia biology.

In research contexts, centrin-2 serves as a centrosomal and basal body marker and is studied in relation to ciliopathies and cancer biology, where centrosome abnormalities are often observed. The protein is widely used to explore the mechanics of centrosome duplication and ciliogenesis.