Anti-Cytokeratin-20 Antibody, clone XQ1 clone XQ1, from mouse

Keratin, type I cytoskeletal 20 (UniProt: Q9D312; also known as Cytokeratin-20, CK-20, Keratin-20, K20) is encoded by the Krt20 gene (Gene ID: 66809) in murine species. Cytokeratin-20 is type I keratin of the intermediate filament family and is recognized as a marker of intestinal differentiation. It is expressed at low levels in the more differentiated suprabasal regions of the small intestine, and at higher levels in the colon, mainly in the upper region and in scattered cells throughout the remaining epithelium. Cytokeratin-20 is also an excellent marker for certain types of carcinomas, such as adenocarcinomas of the colon, transitional cell carcinomas of the bladder and Merkel cell tumors of the skin. It plays a significant role in maintaining keratin filament organization in intestinal epithelia and when phosphorylated, it also plays a role in the secretion of mucin in the small intestine. Cytokeratin-20 can undergo hyperphosphorylation at serine 13 during the early stages of apoptosis, which becomes less prominent during the later stages. Phosphorylation at serine 13 is shown to increase in response to stress brought on by cell injury. During apoptosis it is cleaved at Asp 235 by caspases. (Ref.: Moll, R., et al. (1992). Am. J. Pathol. 140(2); 427-447).