Essential for the proper assembly of type I and type II keratin protein complexes and formation of keratin intermediate filaments in the inner root sheath (irs).
Subcellular locations: Cytoplasm
Strongly expressed in skin and scalp. In the hair follicle, expressed in Henle layer, Huxley layer and in the inner root sheath cuticle of the hair follicle. Expression extends from the bulb region up to the point of differentiation into the three layers. Also present in the medulla of beard hair (at protein level).