We have investigated the expression of 52 of the 54 keratins in beard hair medulla. We found that not only 12 hair keratins but, unexpectedly, also 12 epithelial keratins are potentially expressed in medulla cells. The latter comprise keratins also present in outer- and inner-root sheaths and in the companion layer. Keratins K5, K14, K17, K25, K27, K28, and K75 define a "pre-medulla," composed of cells apposed to the upper dermal papilla. Besides K6, K16, K7, K19, and K80, all pre-medullary epithelial keratins continue to be expressed in the medulla proper, along with the 12 hair keratins. Besides this unique feature of cellular keratin co-expression, the keratin pattern itself is highly variable in individual medulla cells. Remarkably, both epithelial and hair keratins behave highly promiscuously with regard to heterodimer- and IF formation, which also includes keratin chain interactions in IF bundles. We also identified cortex cells within the medullary column. These exhibit all the properties of genuine cortex cells, including a particular type of keratin heterogeneity of their compact IF bundles. In both keratin expression profile and keratin number, medulla cells are distinct from all other cells of the hair follicle or from any other epithelium.
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http://dx.doi.org/10.1038/jid.2009.192 | DOI Listing |
Int J Mol Sci
January 2025
Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu 939-0398, Toyama, Japan.
Recently, we demonstrated that the alopecia observed in vitamin D receptor gene-deficient (-KO) rats is not seen in rats with a mutant VDR(R270L/H301Q), which lacks ligand-binding ability, suggesting that the ligand-independent action of VDR plays a crucial role in maintaining the hair cycle. Since -KO rats also showed abnormalities in the skin, the relationship between alopecia and skin abnormalities was examined. To clarify the mechanism of actions of vitamin D and VDR in the skin, protein composition, and gene expression patterns in the skin were compared among -KO, -R270L/H301Q, and wild-type (WT) rats.
View Article and Find Full Text PDFMethods Mol Biol
December 2024
University of California - Davis, Department of Environmental Toxicology, Davis, CA, USA.
Hair is a ubiquitous and robust mammalian tissue with biological, clinical, forensic, social, and economic significance. The hair shaft proteome reflects both structural proteins, dominated by cuticular intermediate filament keratins and associated proteins, and proteins involved in the final cellular processes of terminally differentiating corneocytes prior to cornification. These distinct biological processes involve cell maintenance, biosynthesis, senescence, and xenobiotic response.
View Article and Find Full Text PDFGenome Biol Evol
January 2025
Department of Dermatology, Medical University of Vienna, Vienna 1090, Austria.
The evolution of cornified skin appendages, such as hair, feathers, and claws, is closely linked to the evolution of proteins that establish the unique mechanical stability of these epithelial structures. We hypothesized that the evolution of the limbless body anatomy of the Florida worm lizard (Rhineura floridana) and the concomitant loss of claws had led to the degeneration of genes with claw-associated functions. To test this hypothesis, we investigated the evolution of three gene families implicated in epithelial cell architecture, namely type I keratins, type II keratins, and genes of the epidermal differentiation complex in R.
View Article and Find Full Text PDFWorld J Microbiol Biotechnol
December 2024
Facultad de Ciencias Exactas, Instituto de Investigaciones para la Industria Química (INIQUI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Salta, Salta, 4400, Argentina.
Leather industry is traditionally characterized by the use of large amounts of chemical agents, some of which are toxic to human health and the environment. However, during the last years, many efforts have been made with the aim of successfully implement enzymes as agents for different leather production stages. The lipopeptides produced by the Bacillus spp.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2024
Centre for Cellular and Molecular Biology, Habsiguda, Uppal Road, Hyderabad, 500007, Telangana, India. Electronic address:
Hair loss condition is heritable and is influenced by multifactorial inheritance. In the present study, spontaneously mutated mice showed hair loss phenotype with defect in the first cycle of hair follicle formation leading to cyclic alopecia. These mutant mice follow autosomal recessive inheritance pattern.
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