title: Immunolocalization and characterization of cornification proteins in snake epidermis.
abstract: Little is known about specific proteins involved in keratinization of the epidermis of snakes, which is composed of alternating beta- and alpha-keratin layers. Using immunological techniques (immunocytochemistry and immunoblotting), the present study reports the presence in snake epidermis of proteins with epitopes that cross-react with certain mammalian cornification proteins (loricrin, filaggrin, sciellin, transglutaminase) and chick beta-keratin. alpha-keratins were found in all epidermal layers except in the hard beta- and alpha-layers. beta-keratins were exclusively present in the oberhautchen and beta-layer. After extraction and electrophoresis, alpha-keratins of 40-67 kDa in molecular weights were found. Loricrin-like proteins recorded molecular weights of 33, 50, and 58 kDa; sciellin, 55 and 62 kDa; filaggrin-like, 52 and 65 kDa; and transglutaminase, 45, 50, and 56 kDa. These results suggest that alpha-layers of snake epidermis utilize proteins with common epitopes to those present during cornification of mammalian epidermis. The beta-keratin antibody on extracts from whole snake epidermis showed a strong cross-reactive band at 13-16 kDa. No cross-reactivity was seen using an antibody against feather beta-keratin, indicating absence of a common epitope between snake and feather keratins.
authors.affiliation: Dipartimento di Biologia Evoluzionistica Sperimentale, University of Bologna, Bologna, Italy. alibardi@biblio.cib.unibo.it
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Alibardi
authors.forename: Mattia
authors.initials: M
authors.lastname: Toni
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism*; D003429:Cross Reactions; D004817:Epidermis / Q000276:immunology / Q000378:metabolism*; D000091344:Filaggrin Proteins; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D007381:Intermediate Filament Proteins / Q000276:immunology / Q000378:metabolism*; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D007633:Keratins / Q000378:metabolism; D008565:Membrane Proteins / Q000276:immunology / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism; D012911:Snakes / Q000276:immunology / Q000378:metabolism*; D011503:Transglutaminases / Q000276:immunology / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; C111281:SCEL protein, human; C064554:loricrin; D007633:Keratins; D011503:Transglutaminases