The expression of equine keratins K42 and K124 is restricted to the hoof epidermal lamellae of Equus caballus

Autoři: Caitlin Armstrong aff001;  Lynne Cassimeris aff002;  Claire Da Silva Santos aff002;  Yagmur Micoogullari aff002;  Bettina Wagner aff003;  Susanna Babasyan aff003;  Samantha Brooks aff004;  Hannah Galantino-Homer aff001
Působiště autorů: Department of Clinical Studies, New Bolton Center, University of Pennsylvania, School of Veterinary Medicine, Kennett Square, Pennsylvania, United States of America aff001;  Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, United States of America aff002;  Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America aff003;  Department of Animal Sciences and University of Florida Genetics institute, University of Florida, Gainesville, Florida, United States of America aff004
Vyšlo v časopise: PLoS ONE 14(9)
Kategorie: Research Article
doi: 10.1371/journal.pone.0219234


The equine hoof inner epithelium is folded into primary and secondary epidermal lamellae which increase the dermo-epidermal junction surface area of the hoof and can be affected by laminitis, a common disease of equids. Two keratin proteins (K), K42 and K124, are the most abundant keratins in the hoof lamellar tissue of Equus caballus. We hypothesize that these keratins are lamellar tissue-specific and could serve as differentiation- and disease-specific markers. Our objective was to characterize the expression of K42 and K124 in equine stratified epithelia and to generate monoclonal antibodies against K42 and K124. By RT-PCR analysis, keratin gene (KRT) KRT42 and KRT124 expression was present in lamellar tissue, but not cornea, haired skin, or hoof coronet. In situ hybridization studies showed that KRT124 localized to the suprabasal and, to a lesser extent, basal cells of the lamellae, was absent from haired skin and hoof coronet, and abruptly transitions from KRT124-negative coronet to KRT124-positive proximal lamellae. A monoclonal antibody generated against full-length recombinant equine K42 detected a lamellar keratin of the appropriate size, but also cross-reacted with other epidermal keratins. Three monoclonal antibodies generated against N- and C-terminal K124 peptides detected a band of the appropriate size in lamellar tissue and did not cross-react with proteins from haired skin, corneal limbus, hoof coronet, tongue, glabrous skin, oral mucosa, or chestnut on immunoblots. K124 localized to lamellar cells by indirect immunofluorescence. This is the first study to demonstrate the localization and expression of a hoof lamellar-specific keratin, K124, and to validate anti-K124 monoclonal antibodies.

Klíčová slova:

Equines – Horses – Immunoblotting – Reverse transcriptase-polymerase chain reaction – Keratins – Nails – Monoclonal antibodies


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