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Hybrid Clear/Blue Native Electrophoresis for the Separation and Analysis of Mitochondrial Respiratory Chain Supercomplexes
Published on: May 19, 2019
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Mitochondrial respiratory chain function promotes extracellular matrix integrity in cartilage.
Kristina Bubb1, Tatjana Holzer1, Janica L Nolte2
1Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany; Center for Biochemistry, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany.
The Journal of Biological Chemistry
|September 24, 2021
Summary
Mitochondrial dysfunction in cartilage disrupts energy metabolism, leading to altered extracellular matrix (ECM) composition and increased stiffness. This study reveals a novel link between cellular energy and tissue structure, impacting cartilage integrity.
Area of Science:
- Biochemistry
- Cell Biology
- Tissue Engineering
Background:
- Energy metabolism and extracellular matrix (ECM) are crucial for tissue organization, but their interaction is not well understood.
- Cartilage relies on a specialized ECM for skeletal growth and lifelong mobility.
Purpose of the Study:
- To investigate the role of the mitochondrial respiratory chain in maintaining ECM homeostasis in mature cartilage.
- To uncover the crosstalk between energy metabolism and ECM function in chondrocytes.
Main Methods:
- Single-cell RNA-Seq (scRNA-Seq) was used to analyze gene expression in cartilage.
- Mass spectrometry/matrisome analysis and atomic force microscopy were employed to assess ECM composition and mechanical properties.
- Genetic inactivation of respiratory chain function in cartilage-specific mouse models was performed.
Main Results:
- Mitochondrial respiratory chain dysfunction led to cartilage expansion, disorganized chondrocytes, and increased ECM deposition.
- scRNA-Seq revealed decreased mitochondrial DNA-encoded respiratory chain genes and altered ECM-related gene regulation in chondrocytes.
- ECM composition changed, with increased collagen crosslinking and ECM stiffness observed.
Conclusions:
- Mitochondrial respiratory chain dysfunction is a key factor influencing ECM integrity and mechanostability in cartilage.
- This finding has implications for understanding tissue organization and potential therapeutic strategies in other tissues as well.
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