Purification, Molecular Cloning, and Expression of a Human Stratum Corneum Trypsin-like Serine Protease with Possible Function in Desquamation

作者：Maria Brattsand, Torbjörn Egelrud · 发表于：Journal of Biological Chemistry · 年份：1999 · DOI：10.1074/jbc.274.42.30033 · 被引用次数：218 · 研究领域：Silk-based biomaterials and applications、Enzyme Production and Characterization、Protein Hydrolysis and Bioactive Peptides

A new human 33-kDa serine protease was purified from human epidermis, and its cDNA was cloned from a keratinocyte library, from mRNA from a human keratinocyte line (HaCat) and from mRNA from human skin. Polyclonal antibodies specific for the new protein detected three groups of proteins in partially purified extracts of cornified eptihelium of human plantar skin. The three components are proposed to correspond to proenzyme, active enzyme, and proteolytically modified active enzyme. After N-deglycosylation, there was a decrease in apparent molecular mass of all detected components. Expression of the cloned cDNA in a eukaryotic virus-derived system yielded a recombinant protein that could be converted to an active protease by treatment with trypsin. Polymerase chain reaction analyses of cDNA from a number of human tissues showed high expression of the new enzyme in the skin and low expression in brain, placenta, and kidney. Homology searches yielded the highest score for porcine enamel matrix protease (55% amino acid sequence homology). High scores were also obtained for human and mouse neuropsin and for human stratum corneum chymotryptic enzyme. The function of this new protease, tentatively named stratum corneum tryptic enzyme, may be related to stratum corneum turnover and desquamation in the epidermis.