Type II Epithelial Keratin 6hf (K6hf) Is Expressed in the Companion Layer, Matrix, and Medulla in Anagen-Stage Hair Follicles

The study examined the expression of Type II Epithelial Keratin 6hf (K6hf) in mouse hair follicles during the anagen stage, finding it in the companion layer, matrix, and medulla, and regulated in a hair-cycle-dependent manner. K6hf was also present in the nail bed epithelium and fungiform papillae of the tongue. The research suggested a partnership between K6hf and keratin 17, as reduced K6hf levels were observed in keratin 17 null hair. The study provided insights into the spatial organization of cellular precursors in the hair matrix and the potential role of Wnt signaling in regulating K6hf expression, highlighting its distinct expression patterns and functional roles in hair and nail tissues.