CCDC89 (Coiled-coil domain-containing protein 89) is a type II transmembrane protein containing a typical coiled-coil domain, primarily localized to the Golgi apparatus and intracellular vesicle membranes. Its function has not yet been fully elucidated, but studies suggest that it acts as a "molecular scaffold" by mediating protein-protein interactions, playing roles in vesicular trafficking, cytoskeletal organization, and the assembly of multiprotein complexes, thereby maintaining cellular structural integrity and coordinating signal transduction. Currently, CCDC89 is emerging as a novel biomarker and potential therapeutic target bridging membrane trafficking, protein homeostasis, tumor biology, and reproductive medicine.