| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 College of Biomedical Science, Florida Atlantic University, Boca Raton, Florida 33431, USA
2 Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
(RECEIVED May 2, 2007; FINAL REVISION May 22, 2007; ACCEPTED May 22, 2007)
The tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of the matrix metalloproteinases (MMPs). Since unregulated MMP activities are linked to arthritis, cancer, and atherosclerosis, TIMP variants that are selective inhibitors of disease-related MMPs have potential therapeutic value. The structures of TIMP/MMP complexes reveal that most interactions with the MMP involve the N-terminal pentapeptide of TIMP and the C–D 
-strand connector which occupy the primed and unprimed regions of the active site. The loop between -strands A and B forms a secondary interaction site for some MMPs, ranging from multiple contacts in the TIMP-2/membrane type-1 (MT1)-MMP complex to none in the TIMP-1/MMP-1 complex. TIMP-1 and its inhibitory domain, N-TIMP-1, are weak inhibitors of MT1-MMP; inhibition is not improved by grafting the longer AB loop from TIMP-2 into N-TIMP-1, but this change impairs binding to MMP-3 and MMP-7. Mutational studies with N-TIMP-1 suggest that its weak inhibition of MT1-MMP, as compared to other N-TIMPs, arises from multiple (>3) sequence differences in the interaction site. Substitutions for Thr2 of N-TIMP-1 strongly influence MMP selectivity; Arg and Gly, that generally reduce MMP affinity, have less effect on binding to MMP-9. When the Arg mutation is added to the N-TIMP-1(AB2) mutant, it produces a gelatinase-specific inhibitor with Ki values of 2.8 and 0.4 nM for MMP-2 and -9, respectively. Interestingly, the Gly mutant has a Ki of 2.1 nM for MMP-9 and >40 µM for MMP-2, indicating that engineered TIMPs can discriminate between MMPs in the same subfamily.
Keywords: matrix metalloproteinase; metalloproteinase inhibition; protein engineering; inhibitory specificity; membrane-type matrix metalloproteinase; interaction interface
Abbreviations: TIMP, tissue inhibitor of metalloproteinase; N-TIMP, N-terminal inhibitory domain of TIMP; MMP, matrix metalloproteinase; MT-MMP, membrane type-matrix metalloproteinase; FnII, fibronectin type II domain;
C, C-terminally truncated; CD, catalytic domain; Ki (app), apparent inhibition constant. Article published online ahead of print. Article and publication date are at http://www.proteinscience.org/cgi/doi/10.1110/ps.072978507.
CiteULike 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  J. L. Lauer-Fields, J. K. Whitehead, S. Li, R. P. Hammer, K. Brew, and G. B. Fields Selective Modulation of Matrix Metalloproteinase 9 (MMP-9) Functions via Exosite Inhibition J. Biol. Chem., July 18, 2008; 283(29): 20087 - 20095. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Higashi and K. Miyazaki Identification of Amino Acid Residues of the Matrix Metalloproteinase-2 Essential for Its Selective Inhibition by {beta}-Amyloid Precursor Protein-derived Inhibitor J. Biol. Chem., April 11, 2008; 283(15): 10068 - 10078. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
