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Mitochondrial respiratory supercomplexes in mammalian cells: structural versus functional role.
Sabzali Javadov1, Sehwan Jang2, Xavier R Chapa-Dubocq2
1Department of Physiology, University of Puerto Rico School of Medicine, San Juan, PR, 00936-5067, USA. sabzali.javadov@upr.edu.
Journal of Molecular Medicine (Berlin, Germany)
|November 17, 2020
Summary
Mitochondrial respiratory supercomplexes (SCs) are key to cellular energy production. This review explores SC assembly mechanisms and their potential roles, reconciling different structural models.
Area of Science:
- Mitochondrial biology
- Cellular respiration
- Biochemistry
Background:
- Mitochondria generate ATP via oxidative phosphorylation through the electron transport chain (ETC).
- Debate exists regarding ETC complex organization: "solid-state" vs. "fluid-state" models.
- Respiratory supercomplexes (SCs) are macromolecular assemblies of ETC complexes.
Purpose of the Study:
- To review the mechanisms and regulation of respiratory supercomplex assembly.
- To discuss the proposed functional roles and challenges to the SC model.
- To explore the "plasticity" model reconciling existing theories.
Main Methods:
- Analysis of macromolecular protein complexes using advanced techniques.
- Blue-native gel electrophoresis, mass spectrometry, and cryogenic electron microscopy.
- Review of studies on SC assembly under physiological and pathological conditions.
Main Results:
- New techniques favor the "solid-state" model, where ETC complexes form SCs.
- Proposed SC functions include substrate channeling and reduced reactive oxygen species production.
- Evidence links SC disintegration to functional changes in disease, though physiological roles remain unclear.
Conclusions:
- The "plasticity" model suggests SCs and individual ETC complexes coexist.
- Understanding SC assembly is crucial for comprehending mitochondrial function and disease.
- Further research is needed to elucidate the precise physiological role of respiratory supercomplexes.
Keywords:
Electron transport chain complexesHuman diseasesInner mitochondrial membraneMitochondriaRespiratory SupercomplexesMore Related Videos
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