CK4 is an alias for the gene, Keratin 4, type II, in humans. Other names include: Keratin, type II cytoskeletal 4; Cytokeratin-4; CK-4; Keratin-4; Type-II keratin Kb4; cytokeratin 4; K4; WSN1. The encoded protein has an amino acid length of 534 and a mass of 57.3 kDa. CK4 is a member of the Intermediate filament family. This gene shares homology with other species, including: Mouse, Zebrafish, Chicken.