Plays a role in the establishment of the epidermal barrier on plantar skin (By similarity). Involved in the maintenance of cell layer development and keratin filament bundles in suprabasal cells of the epithelium (By similarity). Heterotetramer of two type I and two type II keratins. Heterodimer with KRT1 (By similarity). Two heterodimers of KRT1 and KRT10 form a heterotetramer (By similarity). The KRT10 subunit in the heterotetramer is probably disulfide-linked (By similarity). Expressed in skin. There are two types of cytoskeletal and microfibrillar keratin: I (acidic; 40-55 kDa) and II (neutral to basic; 56-70 kDa). Belongs to the intermediate filament family.