Activation mechanisms of the precursors of matrix metalloproteinases 1, 2 and 3.
The zymogens of matrix metalloproteinase 1 (MMP-1: tissue collagenase), MMP-2 (gelatinase/type IV collagenase) and MMP-3 (stromelysin) were purified from the culture medium of human rheumatoid synovial fibroblasts and the mechanisms of activation of each zymogen by proteinases and 4-aminophenylmercuric acetate (APMA) were studied by kinetic and sequence analyses. The treatment of proMMP-1 (M(r) = 52,000) with proteinases or APMA converted the zymogen to M(r) = 43,000, but it exhibited only 14-25% of the maximal activity. Incubation of a partially active MMP-1 with MMP-3 resulted in rapid, full activation by generating the 41,000-M(r) MMP-1 with Phe81 as the NH2-terminus. MMP-3 directly activated proMMP-1 by cleaving the Gln80-Phe81 bond, but this reaction was extremely slow, indicating that the Gln80-Phe81 bond is not readily available to MMP-3 in the native proMMP-1 molecule. ProMMP-2 (M(r) = 72,000) was activated only by APMA, but not by proteinases. The activation by APMA was rapid and generated an active MMP-2 of M(r) 68,000, but the enzymic activity declined rapidly after activation by autolysis. The NH2-terminal sequence analysis of active MMP-2 indicated that the Asn80-Tyr81 bond was cleaved upon APMA treatment. In contrast, proMMP-3 (M(r) = 57,000) was activated by a variety of proteinases with different specificities. The initial attacks of these proteinases are on a stretch of highly charged groups at the position 34-39 in the propeptide.(ABSTRACT TRUNCATED AT 250 WORDS)
Nagase
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Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City 66103.
Suzuki
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K
Morodomi
T
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Enghild
J J
JJ
Salvesen
G
G
D000595:Amino Acid Sequence; D001172:Arthritis, Rheumatoid / Q000473:pathology; D017364:Collagenases / Q000378:metabolism*; D010450:Endopeptidases / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D004792:Enzyme Precursors / Q000737:chemistry / Q000187:drug effects*; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D020781:Matrix Metalloproteinase 1; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D008666:Metalloendopeptidases / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010662:Phenylmercuric Acetate / Q000031:analogs & derivatives* / Q000494:pharmacology; D016415:Sequence Alignment; D013582:Synovial Fluid / Q000166:cytology
D004792:Enzyme Precursors; C010024:4-aminophenylmercuriacetate; D010450:Endopeptidases; D017364:Collagenases; D008666:Metalloendopeptidases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1; D010662:Phenylmercuric Acetate