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Related Experiment Video

Updated: May 7, 2026

Analyzing Supercomplexes of the Mitochondrial Electron Transport Chain with Native Electrophoresis, In-gel Assays, and Electroelution

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Published on: June 1, 2017

Accessory subunits of mitochondrial complex I.

Katarzyna Kmita¹, Volker Zickermann

¹*Medical School, Institute of Biochemistry II, Structural Bioenergetics Group, Cluster of Excellence Frankfurt 'Macromolecular Complexes', Goethe-University Frankfurt, Max-von-Laue Strasse 9, 60438 Frankfurt, Germany.

Biochemical Society Transactions

|September 25, 2013

Summary

Mitochondrial complex I, a large protein assembly, has many accessory subunits whose roles in assembly, stability, and cellular functions beyond energy production are increasingly recognized.

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Area of Science:

Biochemistry
Molecular Biology
Cellular Respiration

Background:

Mitochondrial complex I is a large, multi-subunit enzyme essential for cellular respiration.
Its core functions are primarily attributed to 14 central subunits.
The roles of numerous accessory subunits remain largely unexplored.

Purpose of the Study:

To review the current understanding of accessory subunits in mitochondrial complex I.
To explore their involvement in complex I assembly, stability, and regulation.
To discuss functions of accessory subunits beyond direct energy transduction.

Main Methods:

Literature review of existing research on mitochondrial complex I.
Analysis of studies investigating the structure-function relationships of complex I subunits.
Synthesis of data on the assembly pathways and regulatory mechanisms.

Main Results:

Accessory subunits play critical roles in the proper assembly and stability of mitochondrial complex I.
These subunits are involved in regulating the enzyme's activity, independent of its core bioenergetic functions.
Emerging evidence highlights accessory subunits' involvement in various cellular processes.

Conclusions:

Accessory subunits are crucial for the integrity and function of mitochondrial complex I.
Their roles extend beyond proton translocation, impacting diverse cellular pathways.
Further research into accessory subunits will provide deeper insights into mitochondrial biology and disease.