COX5A Gene

COX5A — Cytochrome C Oxidase Subunit 5A

Introduction

Cox5A Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

<div class="infobox infobox-gene"> [@gandhi2012]
<table> [@stryber2021]
<tr><th colspan="2" style="background:#1a5f7a;color:white;">COX5A — Cytochrome C Oxidase Subunit 5A</th></tr>
<tr><td><strong>Gene Symbol</strong></td><td>COX5A</td></tr>
<tr><td><strong>Full Name</strong></td><td>Cytochrome C Oxidase Subunit 5A</td></tr>
<tr><td><strong>Chromosomal Location</strong></td><td>15q15.3</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[847](https://www.ncbi.nlm.nih.gov/gene/847)</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000178741</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P20674](https://www.uniprot.org/uniprot/P20674)</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>[Alzheimer's Disease](/diseases/alzheimers-disease), [Parkinson's Disease](/diseases/parkinsons-disease), [Mitochondrial Complex IV Deficiency](/diseases/mitochondrial-complex-iv-deficiency)</td></tr>
</table>
</div>

Overview

...

COX5A — Cytochrome C Oxidase Subunit 5A

Introduction

Cox5A Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

<div class="infobox infobox-gene"> [@gandhi2012]
<table> [@stryber2021]
<tr><th colspan="2" style="background:#1a5f7a;color:white;">COX5A — Cytochrome C Oxidase Subunit 5A</th></tr>
<tr><td><strong>Gene Symbol</strong></td><td>COX5A</td></tr>
<tr><td><strong>Full Name</strong></td><td>Cytochrome C Oxidase Subunit 5A</td></tr>
<tr><td><strong>Chromosomal Location</strong></td><td>15q15.3</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[847](https://www.ncbi.nlm.nih.gov/gene/847)</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000178741</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P20674](https://www.uniprot.org/uniprot/P20674)</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>[Alzheimer's Disease](/diseases/alzheimers-disease), [Parkinson's Disease](/diseases/parkinsons-disease), [Mitochondrial Complex IV Deficiency](/diseases/mitochondrial-complex-iv-deficiency)</td></tr>
</table>
</div>

Overview

COX5A encodes cytochrome c oxidase subunit 5A, a crucial component of mitochondrial complex IV (cytochrome c oxidase, COX). Complex IV is the terminal enzyme of the mitochondrial electron transport chain and is responsible for oxidizing cytochrome c and reducing oxygen to water, a process essential for aerobic ATP production.

COX5A is a nuclear-encoded subunit that is imported into mitochondria. It is specifically expressed in tissues with high oxidative metabolism, including:

• Brain ([neurons](/entities/neurons), especially)
• Heart
• Skeletal muscle
• Liver

Function

Mitochondrial Electron Transport Chain

COX5A is part of the core structure of complex IV:

• Contains the cytochrome c binding site
• Participates in electron transfer from cytochrome c to the binuclear center
• Essential for proton pumping across the inner mitochondrial membrane

Regulation

• Heme a and heme a3 are cofactors in the catalytic center
• Expression is regulated by mitochondrial biogenesis factors (PGC-1α)
• Subject to retrograde signaling from mitochondria to nucleus

Tissue-Specific Expression

COX5A expression is particularly high in:

• Neurons — high energy demand for synaptic function
• Cardiac muscle — continuous contraction
• Skeletal muscle — exercise-induced mitochondrial biogenesis

Disease Associations

Alzheimer's Disease

• Reduced COX activity in neurons and platelets
• Mitochondrial dysfunction is an early event in AD pathogenesis
• Impaired oxidative phosphorylation leads to energy deficit
• Correlation with cognitive decline

Parkinson's Disease

• Complex IV deficiency in substantia nigra neurons
• Mitochondrial complex I is primarily affected, but complex IV is also impaired
• Cell death due to energy failure

Mitochondrial Complex IV Deficiency

• Rare but severe
• Can cause Leigh syndrome or encephalomyopathy
• Presents with:
• Lactic acidosis
• Developmental regression
• Motor symptoms

Expression

COX5A expression patterns:

• Brain: Highest in [cortex](/brain-regions/cortex), [hippocampus](/brain-regions/hippocampus), cerebellum
• Heart: Very high (cardiac muscle)
• Skeletal muscle: Exercise-responsive
• Liver: Moderate expression

Expression is regulated by:

• Thyroid hormone
• PGC-1α (mitochondrial biogenesis)
• Hypoxia-inducible factors

Background

The study of Cox5A Gene has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.

Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.

External Links

• [NCBI Gene - COX5A](https://www.ncbi.nlm.nih.gov/gene/847)
• [UniProt - COX5A](https://www.uniprot.org/uniprot/P20674)
• [Ensembl - COX5A](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000178741)
• [OMIM - COX5A](https://www.omim.org/entry/603773)

References

[Parikh et al., Mitochondrial dysfunction in Alzheimer's disease (2009) (2009)](https://doi.org/10.1016/j.neurobiolaging.2007.12.023)

[Gandhi et al., COX deficiency in neurodegeneration (2012) (2012)](https://doi.org/10.1016/j.tibs.2012.06.008)

[Stryber et al., Cytochrome c oxidase in AD brain (2021) (2021)](https://doi.org/10.1007/s12035-021-02345-5)