caution:Was originally (PubMed:2140676) thought to be a 60 kDa chain of placental scatter protein.,disease:Defects in KRT9 are a cause of palmoplantar keratoderma epidermolytic (EPPK) [MIM:144200]; also abbreviated EHPPK. EPPK is a dermatological disorder characterized by diffuse thickening of the epidermis on the entire surface of palms and soles sharply bordered with erythematous margins.,disease:Knuckle pads are sometimes associated with EPPK [MIM:149100]. Knuckle pads consist of an autosomal dominant trait, in which thick pads of skin appear over the proximal phalangeal joints.,function:May serve an important special function either in the mature palmar and plantar skin tissue or in the morphogenetic program of the formation of these tissues. Plays a role in keratin filament assembly.,induction:Induced by intrinsic regulatory mechanisms and by extrinsic signals from a subset of dermal palmoplantar fibroblasts.,miscellaneous:There are two types of cytoskeletal and microfibrillar keratin, I (acidic) and II (neutral to basic) (40-55 and 56-70 kDa, respectively).,similarity:Belongs to the intermediate filament family.,subunit:Heterotetramer of two type I and two type II keratins.,tissue specificity:Expressed in the terminally differentiated epidermis of palms and soles.,
extracellular space,nucleus,intermediate filament,membrane,extracellular exosome,
Expressed in the terminally differentiated epidermis of palms and soles.