Related Experiment Video
Updated: Jun 2, 2026
Detection of Functional Matrix Metalloproteinases by Zymography
Published on: November 8, 2010
Analysis of apolipoprotein A-I as a substrate for matrix metalloproteinase-14
Jun Hyoung Park1, Sung-Min Park, Ki-Hoon Park
1Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea.
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.
Insights
Matrix metalloproteinase-14 (MMP-14) cleaves apolipoprotein A-I (apoA-I), reducing high-density lipoprotein (HDL) formation. This cleavage may contribute to vascular diseases by disrupting lipid metabolism.
Area of Science:
- Biochemistry
- Molecular Biology
- Cardiovascular Research
Background:
- Matrix metalloproteinase-14 (MMP-14) is implicated in various physiological and pathological processes.
- Apolipoprotein A-I (apoA-I) is the primary protein component of high-density lipoprotein (HDL) and plays a crucial role in reverse cholesterol transport.
Purpose of the Study:
- To investigate apolipoprotein A-I (apoA-I) as a substrate for matrix metalloproteinase-14 (MMP-14).
- To determine the impact of MMP-14-mediated cleavage of apoA-I on high-density lipoprotein (HDL) formation and function.
Main Methods:
- In vitro cleavage assays using purified MMP-14 and lipid-free/lipid-bound apoA-I.
- Mass spectrometry and N-terminal sequencing to identify apoA-I cleavage sites.
- Assessment of HDL formation capacity after apoA-I cleavage.
Main Results:
- MMP-14 efficiently cleaves lipid-free apoA-I into multiple fragments, with greater preference over MMP-3.
- Specific cleavage sites on apoA-I were identified by mass spectrometry and sequencing.
- Cleavage of apoA-I by MMP-14 resulted in a significant loss of its ability to form HDL.
Conclusions:
- MMP-14-mediated cleavage of lipid-free apoA-I disrupts HDL formation.
- This process may represent a novel mechanism contributing to the pathogenesis of vascular diseases associated with dyslipidemia.
