Epilysin, a novel human matrix metalloproteinase (MMP-28) expressed in testis and keratinocytes and in response to injury.
We have cloned a new human matrix metalloproteinase (MMP-28, epilysin) from human keratinocyte and testis cDNA libraries. Like most MMPs, epilysin contains a signal sequence, a prodomain with a PRCGVTD sequence, a zinc-binding catalytic domain with an HEIGHTLGLTH sequence, and a hemopexin-like domain. In addition, epilysin has a furin activation sequence (RRKKR) but has no transmembrane sequence. The exon-intron organization and splicing pattern of epilysin differ from that of other MMP genes. It has only 8 exons, and 5 exons are spliced at sites not used by other MMPs. Another novel feature of epilysin is that exon 4 is alternatively spliced to a transcript that does not encode the N-terminal half of the catalytic domain. Northern hybridization of tissue RNA indicated that epilysin is expressed at high levels in testis and at lower levels in lungs, heart, colon, intestine, and brain. RNase protection assay with various cell lines indicated that epilysin was selectively expressed in keratinocytes. Recombinant epilysin degraded casein in a zymography assay, and its proteolytic activity was inhibited by EDTA and by batimastat, a selective MMP inhibitor. Immunohistochemical staining showed expression of epilysin protein in the basal and suprabasal epidermis of intact skin. In injured skin, prominent staining for epilysin was seen in basal keratinocytes both at and some distance from the wound edge, a pattern that is quite distinct from that of other MMPs expressed during tissue repair. These findings suggest that this new MMP functions in several tissues both in tissue homeostasis and in repair.
Lohi
J
J
Departments of Pediatrics (Allergy and Pulmonary Medicine) and Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. jouko.lohi@helsinki.fi
Wilson
C L
CL
Roby
J D
JD
Parks
W C
WC
D000328:Adult; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae / Q000378:metabolism; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D016466:CHO Cells; D002364:Caseins / Q000378:metabolism; D020134:Catalytic Domain; D002460:Cell Line; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary / Q000378:metabolism; D004492:Edetic Acid / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D005091:Exons; D015723:Gene Library; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007438:Introns; D015603:Keratinocytes / Q000378:metabolism*; D008297:Male; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000096:biosynthesis* / Q000235:genetics; D053505:Matrix Metalloproteinases, Secreted; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000494:pharmacology; D010802:Phylogeny; D011480:Protease Inhibitors / Q000494:pharmacology; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012260:Ribonucleases / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000378:metabolism; D013737:Testis / Q000378:metabolism*; D013876:Thiophenes / Q000494:pharmacology; D014018:Tissue Distribution
D002364:Caseins; D018076:DNA, Complementary; D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D011993:Recombinant Fusion Proteins; D013876:Thiophenes; D010649:Phenylalanine; D004492:Edetic Acid; C080985:batimastat; D005982:Glutathione Transferase; D012260:Ribonucleases; C424663:MMP28 protein, human; D020782:Matrix Metalloproteinases; D053505:Matrix Metalloproteinases, Secreted