Molecular cloning, chromosomal localization, and bacterial expression of a murine macrophage metalloelastase.
Murine macrophages have previously been shown to secrete a zinc-dependent proteinase that can degrade elastin. In this report, we identify murine macrophage elastase (MME) cDNA and show that it is a distinct member of the metalloproteinase gene family. Small amounts of MME were purified to homogeneity, and N-terminal amino acid sequence was obtained. This sequence was used to obtain a partial cDNA clone by the polymerase chain reaction; a cDNA library derived from a mouse macrophage-like cell line (P388D1) was screened with this probe. A full-length MME cDNA spanning approximately 1.8 kilobases contained an open reading frame of 1386 base pairs; the predicted molecular mass of the MME proenzyme is 53 kDa. The gene encoding MME is represented only once in the mouse genome and is located on chromosome 9. Despite a size that is similar to other metalloproteinases, MME is distinct, sharing only 33-48% amino acid homology with other metalloproteinases. In contrast to other metalloenzymes, MME appears to be rapidly processed to an active truncated form (N-terminal and C-terminal cleavage). We expressed recombinant MME in Escherichia coli and demonstrated that it has significant elastolytic activity that is specifically inhibited by the tissue inhibitor of metalloproteinases. MME is therefore a true metalloproteinase that may be involved in tissue injury and remodeling.
Shapiro
S D
SD
Department of Medicine, Jewish Hospital, Washington University Medical Center, St. Louis, Missouri 63110.
Griffin
G L
GL
Gilbert
D J
DJ
Jenkins
N A
NA
Copeland
N G
NG
Welgus
H G
HG
Senior
R M
RM
Ley
T J
TJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology*; D015870:Gene Expression; D008264:Macrophages / Q000201:enzymology*; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011480:Protease Inhibitors / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid
D011480:Protease Inhibitors; D012333:RNA, Messenger; D011994:Recombinant Proteins; D004247:DNA; D010196:Pancreatic Elastase; D008666:Metalloendopeptidases