CETN2 (centrin 2) is a calcium-binding protein with diverse cellular functions, primarily involved in centrosome biology and DNA repair mechanisms. As a structural component of centrosomes, CETN2 regulates centriole duplication through phosphorylation by Mps1 kinase, with three key phosphorylation sites required for proper centriole assembly and maturation 1. The protein also functions in nucleotide excision repair (NER) by forming complexes with XPC for DNA damage recognition, contributing to chemotherapy resistance in hepatocellular carcinoma and ovarian cancer 23. CETN2 serves as a novel marker for mature human astrocytes, displaying unique cytoplasmic distribution patterns distinct from its centrosomal localization in proliferating cells 4. In disease contexts, CETN2 expression correlates with Alzheimer's disease severity in astrocytes and is associated with poor prognosis in platinum-resistant cancers 53. The protein is also targeted by bacterial pathogens like Chlamydia trachomatis, which uses the effector CteG to bind CETN2 and induce centrosome amplification 6. Additionally, CETN2 is essential for ciliary function, with defects affecting inner dynein arm assembly in primary ciliary dyskinesia 7.