These collective data suggest that, unlike mouse matriptase, human matriptase may be involved in the regulation of keratinocyte growth and early differentiation, rather than terminal differentiation, providing mechanistic insights into the pathology of the two congenital ichthyoses: ARIH and IFAH.
Two missense mutations in ST14 were recently described in patients with a phenotype of ichthyosis and hypotrichosis, indicating diverse activities of matriptase in the epidermis and hair follicles.
Thus, ST14 hypomorphic mice developed hyperproliferative and retention ichthyosis with impaired desquamation, hypotrichosis with brittle, thin, uneven, and sparse hair, and tooth defects.