CD20,CK20,CK-20,cytokeratin 20,Cytokeratin-20,K20,keratin 20, type I,keratin, type I cytoskeletal 20,Keratin-20,KRT21,protein IT.
Plays a significant role in maintaining keratin filament organization in intestinal epithelia. When phosphorylated, plays a role in the secretion of mucin in the small intestine (By similarity).