CLXN (calaxin), also known as EFCAB1 or ODAD5, is a calcium-binding protein component of the outer dynein arm-docking complex (ODA-DC) essential for ciliary and flagellar function. The protein mediates the assembly and docking of outer dynein arms (ODAs) onto doublet microtubules within the axoneme, thereby regulating ciliary motility and flagellar beating 1. CLXN localizes to ciliary axonemes and functions as part of the ODA-docking machinery; its absence prevents proper localization of critical ODA components including DNAH5, DNAI1, and DNAI2 to distal axonemal regions 1. Beyond its axonemal role, CLXN expression in the left-right organizer suggests involvement in determining body laterality during development 1. Pathogenic variants in CLXN cause primary ciliary dyskinesia (PCD) characterized by outer dynein arm defects, respiratory dysfunction, laterality defects, and reduced fertility 1. Additionally, CLXN shows potential clinical relevance in lung adenocarcinoma, where its expression is significantly downregulated; CLXN overexpression inhibits cancer cell proliferation and migration while promoting apoptosis, suggesting utility as a prognostic biomarker 2. These findings establish CLXN as a multifunctional protein critical for ciliary ultrastructure, motility, and developmental laterality determination.