title: Mice deficient for the epidermal dermokine β and γ isoforms display transient cornification defects.
abstract: Expression of the human dermokine gene (DMKN) leads to the production of four dermokine isoform families. The secreted α, β and γ isoforms have an epidermis-restricted expression pattern, with Dmkn β and γ being specifically expressed by the granular keratinocytes. The δ isoforms are intracellular and ubiquitous. Here, we performed an in-depth characterization of Dmkn expression in mouse skin and found an expression pattern that was less complex than in humans. In particular, mRNA coding for the δ family were absent. Homozygous mice null for the Dmkn β and γ isoforms had no obvious phenotype but only a temporary scaly skin during the first week of life. The pups null for the Dmkn β and γ isoforms had smaller keratohyalin granules and their cornified envelopes were more sensitive to mechanical stress. At the molecular level, amounts of profilaggrin and filaggrin monomers were reduced whereas amino acid components of the natural moisturizing factor were increased. In addition, the electrophoretic mobility of involucrin was modified, suggesting post-translational modifications. Finally, the mice null for the Dmkn β and γ isoforms strongly overexpressed Dmkn α. These data are evocative of compensatory mechanisms relevant to the temporary phenotype. Overall, we improved the knowledge of Dmkn expression in mouse and highlighted a role for Dmkn β and γ in cornification.
authors.affiliation: UMR 5165 / U1056 'Différenciation Epidermique et Autoimmunité Rhumatoïde' (CNRS - INSERM - Université Toulouse III - CHU de Toulouse), Hôpital Purpan, Place du Dr Baylac, TSA 40031, 31059 Toulouse Cedex 9, France.
authors.forename: Emilie A
authors.initials: EA
authors.lastname: Leclerc
authors.affiliation: UMR 5165 / U1056 'Différenciation Epidermique et Autoimmunité Rhumatoïde' (CNRS - INSERM - Université Toulouse III - CHU de Toulouse), Hôpital Purpan, Place du Dr Baylac, TSA 40031, 31059 Toulouse Cedex 9, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Huchenq
authors.affiliation: Coronel Institute of Occupational Health, Academic Medical Center, 1105 Amsterdam, The Netherlands.
authors.forename: Sanja
authors.initials: S
authors.lastname: Kezic
authors.affiliation: UMR 5165 / U1056 'Différenciation Epidermique et Autoimmunité Rhumatoïde' (CNRS - INSERM - Université Toulouse III - CHU de Toulouse), Hôpital Purpan, Place du Dr Baylac, TSA 40031, 31059 Toulouse Cedex 9, France.
authors.forename: Guy
authors.initials: G
authors.lastname: Serre
authors.affiliation: UMR 5165 / U1056 'Différenciation Epidermique et Autoimmunité Rhumatoïde' (CNRS - INSERM - Université Toulouse III - CHU de Toulouse), Hôpital Purpan, Place du Dr Baylac, TSA 40031, 31059 Toulouse Cedex 9, France nathalie.jonca@udear.cnrs.fr.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Jonca
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism*; D005260:Female; D000091344:Filaggrin Proteins; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D020033:Protein Isoforms; D011506:Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D036341:Intercellular Signaling Peptides and Proteins; D020033:Protein Isoforms; D011506:Proteins; C495569:dermokine protein, mouse
keywords: Cornified cell envelope; Dermokine; Dmkn; Keratinocyte differentiation; Stratum corneum