Keratin, type I cytoskeletal 4 also known as cytokeratin-4 (CK-4) or keratin-4 (K4) is a protein that in humans is encoded by the KRT4gene.[5][6]
Keratin 4 is a type II cytokeratin. It is specifically found in differentiated layers of the mucosal and esophageal epithelia together with keratin 13. Mutations in the genes encoding this protein have been associated with White Sponge Nevus, characterized by oral, esophageal, and analleukoplakia.[7]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Barletta C, Batticane N, Ragusa RM, Leube R, Peschle C, Romano V (1990). "Subchromosomal localization of two human cytokeratin genes (KRT4 and KRT15) by in situ hybridization". Cytogenet. Cell Genet. 54 (3–4): 148–50. doi:10.1159/000132979. PMID1702379.
^Chao SC, Tsai YM, Yang MH, Lee JY (June 2003). "A novel mutation in the keratin 4 gene causing white sponge naevus". Br. J. Dermatol. 148 (6): 1125–8. doi:10.1046/j.1365-2133.2003.05337.x. PMID12828738. S2CID26905614.
Barcelos AC, Sotto MN (2009). "Comparative analysis of the expression of cytokeratins (1, 10, 14, 16, 4), involucrin, filaggrin and e-cadherin in plane warts and epidermodysplasia verruciformis plane wart-type lesions". J. Cutan. Pathol. 36 (6): 647–54. doi:10.1111/j.1600-0560.2008.01127.x. PMID19515043. S2CID205816580.
Zhang JM, Yang ZW, Chen RY, et al. (2009). "Two new mutations in the keratin 4 gene causing oral white sponge nevus in Chinese family". Oral Dis. 15 (1): 100–5. doi:10.1111/j.1601-0825.2008.01498.x. PMID18992023.
Presland RB, Dale BA (2000). "Epithelial structural proteins of the skin and oral cavity: function in health and disease". Crit. Rev. Oral Biol. Med. 11 (4): 383–408. doi:10.1177/10454411000110040101. PMID11132762.
Wanner R, Förster HH, Tilmans I, Mischke D (1993). "Allelic variations of human keratins K4 and K5 provide polymorphic markers within the type II keratin gene cluster on chromosome 12". J. Invest. Dermatol. 100 (6): 735–41. doi:10.1111/1523-1747.ep12475671. PMID7684424.
Wanner R, Zhang J, Dorbic T, et al. (1997). "The promoter of the HaCaT keratinocyte differentiation-related gene keratin 4 contains a functional AP-2 binding site". Arch. Dermatol. Res. 289 (12): 705–8. doi:10.1007/s004030050265. PMID9452892. S2CID7854003.
Romano V, Bosco P, Rocchi M, et al. (1988). "Chromosomal assignments of human type I and type II cytokeratin genes to different chromosomes". Cytogenet. Cell Genet. 48 (3): 148–51. doi:10.1159/000132612. PMID2466616.