A new inhibitor of metalloproteinases from chicken: ChIMP-3. A third member of the TIMP family.
We report cDNA cloning and primary structure of a new metalloproteinase inhibitor (ChIMP-3) produced by chicken embryo fibroblasts. ChIMP-3, formerly called the 21-kDa protein, is one of five ChIMPs (Chicken Inhibitor of MetalloProteinases). In this paper, we report that of the three most abundant ChIMPs, ChIMP-3 and ChIMP-a are extracellular matrix components, whereas ChIMP-2 is found in the media conditioned by the cells. Treatment of ChIMP-3 and ChIMP-a with N-glycosidase-F indicates that ChIMP-a is N-glycosylated whereas ChIMP-3 is not. The deduced amino acid sequence of ChIMP-3 predicts a protein whose properties are consistent with experimental measurements. Analysis of sequence alignments with the two previously described members of the TIMP (tissue inhibitor of metalloproteinases) family, TIMP-1 and TIMP-2, from various species indicates that ChIMP-3 is a related but distinct protein. This conclusion is supported by lack of significant binding with anti-TIMP-1 and anti-TIMP-2 antibodies. Based on these data, its unusual solubility properties, and its exclusive location in the matrix, we propose that ChIMP-3 is a new member of this family of metalloproteinase inhibitors, a TIMP-3.
Pavloff
N
N
Department of Pharmacy, School of Pharmacy, University of California, San Francisco 94143-0446.
Staskus
P W
PW
Kishnani
N S
NS
Hawkes
S P
SP
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D002642:Chick Embryo; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics* / Q000302:isolation & purification; D006023:Glycoproteins / Q000235:genetics*; D006026:Glycoside Hydrolases; D006031:Glycosylation; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D005810:Multigene Family; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000235:genetics* / Q000302:isolation & purification; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D012984:Software; D019717:Tissue Inhibitor of Metalloproteinase-3; D019714:Tissue Inhibitor of Metalloproteinases
D006023:Glycoproteins; D009838:Oligodeoxyribonucleotides; D011506:Proteins; D019717:Tissue Inhibitor of Metalloproteinase-3; D019714:Tissue Inhibitor of Metalloproteinases; D004247:DNA; D006026:Glycoside Hydrolases; D008666:Metalloendopeptidases