Retinoic acid induces transglutaminase activity but inhibits cornification of cultured epidermal cells.
In cultured mouse epidermal basal cells, retinoic acid is a potent inducer of transglutaminase, the enzyme responsible for isodipeptide bond formation in protein cross-linking in the production of the cornified membrane during terminal differentiation. Paradoxically retinoic acid also inhibits the formation of the cross-linked envelope and greatly reduces the level of dipeptide bond formation in epidermal cells induced to differentiate by calcium. These results suggest a novel mechanism by which retinoids can modify transglutaminase activity and epidermal differentiation.
D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D004789:Enzyme Activation; D007700:Kinetics; D051379:Mice; D012867:Skin / Q000187:drug effects / Q000201:enzymology; D012879:Skin Physiological Phenomena; D014212:Tretinoin / Q000494:pharmacology*; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
D014212:Tretinoin; D005723:gamma-Glutamyltransferase