Analysis of apolipoprotein A-I as a substrate for matrix metalloproteinase-14.

Abstract

Substrates for matrix metalloproteinase (MMP)-14 were previously identified in human plasma using proteomic techniques. One putative MMP-14 substrate was apolipoprotein A-I (apoA-I), a major component of high-density lipoprotein (HDL). In vitro cleavage assays showed that lipid-free apoA-I is a more accessible substrate for MMP-14 compared to lipid-bound apoA-I, and that MMP-14 is more prone to digest apoA-I than MMP-3. The 28-kDa apoA-I was cleaved into smaller fragments of 27, 26, 25, 22, and 14-kDa by MMP-14. ApoA-I sites cleaved by MMP-14 were determined by isotope labeling of C-termini derived from the cleavage and analysis of the labeled peptides by mass spectrometry, along with N-terminal sequencing of the fragments. Cleavage of apoA-I by MMP-14 resulted in a loss of ability to form HDL. Our results suggest that cleavage of lipid-free apoA-I by MMP-14 may contribute to reduced HDL formation, and this may be occurring during the development of various vascular diseases as lipid metabolism is disrupted.

• Authors: Jun Hyoung Park, Sung-Min Park, Ki-Hoon Park, Kyung-Hyun Cho, Seung-Taek Lee
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 409 Issue 1 Pg. 58-63 (May 27 2011) ISSN: 1090-2104 [Electronic] United States
• PMID: 21549099 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Inc. All rights reserved.

Chemical References

• Apolipoprotein A-I
• Blood Proteins
• MMP14 protein, human
• Matrix Metalloproteinase 14

Topics

• Apolipoprotein A-I (blood, chemistry)
• Blood Proteins (chemistry)
• Humans
• Matrix Metalloproteinase 14 (chemistry)
• Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
• Substrate Specificity