ANAPC16 is a structural subunit of the anaphase promoting complex/cyclosome (APC/C), a cell cycle-regulated E3 ubiquitin ligase essential for mitotic progression 1. As part of the APC/C's "Arc Lamp" hub, ANAPC16 mediates assembly of the complex and facilitates ubiquitination of cell cycle regulatory proteins through formation of Lys-11-linked polyubiquitin chains, with secondary Lys-48 and Lys-63 linkages 12. Structurally, ANAPC16 binds asymmetrically to the APC3 dimer and recruits APC7 to the complex, stabilizing APC/C composition and regulating its catalytic activity 3. ANAPC16 is required for APC7 assembly into APC/C, though it assembles independently of APC7 4. Deletion of ANAPC16 reduces APC/C ubiquitylation activity in vitro while maintaining mitotic progression and spindle assembly checkpoint function in human cells 4. Clinically, reduced ANAPC16 expression is associated with poor prognosis and biochemical recurrence-free survival in prostate cancer patients 5. Additionally, genetic variants in ANAPC16 have been implicated in refractive error and myopia pathogenesis through TGF-beta signaling regulation 6, suggesting broader roles in development and disease beyond cell cycle control.