title: Synthesis of porcine pCLCA2 protein during late differentiation of keratinocytes of epidermis and hair follicle inner root sheath.
abstract: Despite the discovery of the widely expressed CLCA (chloride channel regulators, calcium-activated) proteins more than 15 years ago, their seemingly diverse functions are still poorly understood. With the recent generation of porcine animal models for cystic fibrosis (CF), members of the porcine CLCA family are becoming of interest as possible modulators of the disease in the pig. Here, we characterize pCLCA2, the porcine ortholog of the human hCLCA2 and the murine mCLCA5, which are the only CLCA members expressed in the skin. Immunohistochemical studies with a specific antibody against pCLCA2 have revealed a highly restricted pCLCA2 protein expression in the skin. The protein is strictly co-localized with filaggrin and trichohyalin in the granular layer of the epidermis and the inner root sheath of the hair follicles, respectively. No differences have been observed between the expression patterns of wild-type pigs and CF transmembrane conductance regulator(-/-) pigs. We speculate that pCLCA2 plays an as yet undefined role in the structural integrity of the skin or, possibly, in specialized functions of the epidermis, including barrier or defense mechanisms.
authors.affiliation: Department of Veterinary Pathology, Faculty of Veterinary Medicine, Freie Universität Berlin, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Plog
authors.forename: Lars
authors.initials: L
authors.lastname: Mundhenk
authors.forename: Lutz
authors.initials: L
authors.lastname: Langbein
authors.forename: Achim D
authors.initials: AD
authors.lastname: Gruber
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D002454:Cell Differentiation / Q000502:physiology; D018118:Chloride Channels / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism*; D005260:Female; D000091344:Filaggrin Proteins; D057809:HEK293 Cells; D018859:Hair Follicle / Q000166:cytology* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000378:metabolism; D015603:Keratinocytes / Q000166:cytology* / Q000378:metabolism*; D007633:Keratins / Q000378:metabolism; D008297:Male; D051379:Mice; D018613:Microscopy, Confocal; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012867:Skin / Q000166:cytology / Q000378:metabolism; D013552:Swine; D014162:Transfection
chemical_list: D018118:Chloride Channels; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D012333:RNA, Messenger; C016159:trichohyalin; D007633:Keratins