ATP7A

ATP7A — Copper-Transport ATPase

Introduction

```mermaid
flowchart TD
classDef gene fill:#0a1f0a,stroke:#4caf50
classDef protein fill:#0a1929,stroke:#2196f3
classDef disease fill:#2d0f0f,stroke:#e91e63
classDef pathway fill:#3e2200,stroke:#ff9800
classDef mechanism fill:#1a0a1f,stroke:#9c27b0
classDef therapeutic fill:#e0f2f1,stroke:#009688
ATP7A["ATP7A"] -->|"implicated_in"| neurodegeneration["neurodegeneration"]
ATP7A["ATP7A"] ==>|"activates"| P53["P53"]
ATP7A["ATP7A"] -->|"expressed_in"| SOD1["SOD1"]
ATP7A["ATP7A"] -->|"expressed_in"| SP1["SP1"]
ATP7A["ATP7A"] -.->|"inhibits"| Als["Als"]
ATP7A["ATP7A"] -->|"expressed_in"| Ms["Ms"]
ATP7A["ATP7A"] -->|"expressed_in"| ABCG1["ABCG1"]
ATP7A["ATP7A"] -->|"expressed_in"| SLC22A5["SLC22A5"]
ATP7A["ATP7A"] -->|"expressed_in"| CANCER["CANCER"]
ATP7A["ATP7A"] -->|"expressed_in"| ABCG2["ABCG2"]
ATP7A["ATP7A"] -->|"expressed_in"| Cancer["Cancer"]
ATP7A["ATP7A"] -.->|"inhibits"| Carcinoma["Carcinoma"]
ATP7A["ATP7A"] -->|"causes"| Menkes_disease["Menkes disease"]
ATP7A["ATP7A"] -->|"regulates"| copper["copper"]
ATP7A["ATP7A"] -->|"participates_in"| copper_transport["copper transport"]
ATP7A["ATP7A"] -->|"associated_with"| neurodegeneration["neurodegeneration"]
ATP7A["ATP7A"] -->|"associated_with"| developmental_delay["developmental delay"]
ATP7A["ATP7A"] -->|"expressed_in"| Alzheimer["Alzheimer"]
ATP7A["ATP7A"] -->|"expressed_in"| Oxidative_Stress["Oxidative Stress"]
ATP7A["ATP7A"] -->|"expressed_in"| Blood_Brain_Barrier["Blood-B

...

ATP7A — Copper-Transport ATPase

Introduction

Atp7A 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"> [@vulpe1993]
<table> [@kodama2019]
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">ATPase 7A</th></tr> [@nobuta2019]
<tr><td><strong>Gene Symbol</strong></td><td>ATP7A</td></tr> [@white2020]
<tr><td><strong>Full Name</strong></td><td>ATPase 7A (Copper Transporting ATPase)</td></tr> [@davies2013]
<tr><td><strong>Chromosome</strong></td><td>Xq21.1</td></tr> [@bertini2008]
<tr><td><strong>NCBI Gene ID</strong></td><td>[538](https://www.ncbi.nlm.nih.gov/gene/538)</td></tr> [@kaler2011]
<tr><td><strong>OMIM</strong></td><td>300011</td></tr>
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000136939</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[Q9Y5K9](https://www.uniprot.org/uniprot/Q9Y5K9)</td></tr>
<tr><td><strong>Protein Length</strong></td><td>1500 amino acids</td></tr>
<tr><td><strong>Molecular Weight</strong></td><td>163 kDa</td></tr>
<tr><td><strong>Associated Diseases</strong></td><td>Menkes Disease, Occipital Horn Syndrome, [Alzheimer's Disease](/diseases/alzheimers-disease)</td></tr>
</table>
</div>

Overview

ATP7A (ATPase 7A) encodes a P-type copper-transporting ATPase that is essential for systemic copper homeostasis. This transmembrane protein is responsible for copper absorption from the intestine, distribution to peripheral tissues, and incorporation into copper-dependent enzymes. ATP7A is expressed in most tissues except the liver, making it the primary copper transporter for extrahepatic copper metabolism.

Mutations in ATP7A cause Menkes disease, a severe X-linked recessive disorder characterized by progressive neurodegeneration, connective tissue abnormalities, and early death if untreated. The disease results from impaired copper absorption and distribution, leading to severe copper deficiency in the brain and other tissues. Interestingly, emerging research suggests ATP7A dysfunction may also play a role in Alzheimer's disease and other neurodegenerative conditions.

Structure

ATP7A is a large transmembrane protein of 1500 amino acids with a molecular weight of approximately 163 kDa. Like ATP7B, it belongs to the P-type ATPase family and contains similar structural domains:

Transmembrane Domain

• 8 Transmembrane Helices: Form the copper translocation pore
• Copper Binding Sites: 6 N-terminal CXXC motifs for copper binding
• Gate Region: Regulates access to the transport channel

Functional Domains

• N-terminal Metal-Binding Domain: Contains multiple copper-binding motifs
• Phosphorylation Domain: Conserved DKTGTLT motif
• Actuator Domain: Facilitates conformational changes
• ATP-binding Domain: Catalyzes ATP hydrolysis

Molecular Function

Copper Transport Mechanism

ATP7A operates through a similar mechanism to ATP7B:

Copper Binding: Copper ions bind to N-terminal metal-binding sites

ATP Hydrolysis: Energy from ATP drives conformational changes

Translocation: Copper is transported across the membrane

Release: Copper is released into the extracellular space or incorporated into enzymes

Reset: Return to original conformation

Physiological Roles

• Intestinal Absorption: Primary transporter for dietary copper uptake
• Systemic Distribution: Delivers copper to peripheral tissues
• Enzyme Maturation: Supplies copper to Cu/ZN superoxide dismutase, cytochrome c oxidase
• [Blood-Brain Barrier](/entities/blood-brain-barrier) Transport: Essential for copper entry into the brain

Expression

Tissue Distribution

ATP7A is widely expressed with highest levels in:

• Intestinal Epithelium: Small intestine enterocytes
• Placenta: Trophoblast cells
• Brain: [Neurons](/entities/neurons), endothelial cells of BBB
• Kidney: Tubular cells
• Heart: Cardiomyocytes
• Lung: Alveolar epithelium

Subcellular Localization

ATP7A localizes to:

• Plasma Membrane: Basolateral membrane of intestinal cells
• Trans-Golgi Network: For enzyme copper delivery
• Endosomes: Mobile pool for copper distribution

Role in Neurodegeneration

Menkes Disease

Menkes disease results from ATP7A deficiency:

• Neurological Features: Severe developmental delay, hypotonia, seizures
• Connective Tissue: Hyperextensible skin, joint hypermobility, vascular tortuosity
• Hair Abnormalities: Kinky, brittle hair (pili torti)
• Failure to Thrive: Growth retardation
• Early Mortality: Usually within early childhood without treatment

The neuropathology includes:

• Cerebellar atrophy
• White matter abnormalities
• Neuronal loss
• Dendritic abnormalities

Occipital Horn Syndrome

A milder allelic variant:

• Skeletal abnormalities (occipital horns)
• Mild neurological involvement
• Longer survival

Alzheimer's Disease

ATP7A implications in AD:

• Copper Homeostasis: Altered in AD brain
• Amyloid Processing: Affects [Aβ](/proteins/amyloid-beta) generation and aggregation
• Oxidative Stress: Modulates [ROS](/entities/reactive-oxygen-species) production
• Blood-Brain Barrier: Affects copper entry to brain

Other Neurodegenerative Conditions

• [Parkinson's Disease](/diseases/parkinsons-disease): Altered neuronal copper handling
• Amyotrophic Lateral Sclerosis: Copper metabolism in motor neurons
• Prion Disease: Copper-binding in prion protein metabolism

Therapeutic Implications

Menkes Disease Treatment

Current therapies include:

• Copper Histidine: Subcutaneous copper supplementation
• Early Intervention: Critical for neurological outcomes
• Gene Therapy: Experimental AAV-mediated delivery

Neurodegeneration Research

ATP7A-targeted approaches:

• Copper Delivery: Enhancing brain copper levels
• Gene Therapy: Restoring ATP7A function
• Protein Modulators: Pharmacological chaperones
• BBB-Penetrant Copper Compounds: Targeted delivery

Drug Development

Pharmaceutical strategies:

• Copper Ionophores: Facilitate copper entry into cells
• ATP7A Expression Modulators: Increase protein levels
• Protein Stabilizers: Rescue mutant protein function

Animal Models

Knockout Models

Atp7a knockout mice:

• Embryonic lethality (most die in utero)
• Phenocopy Menkes disease
• Copper deficiency in brain

Conditional Knockouts

Tissue-specific knockouts reveal:

• Neuronal knockout: Neurodegeneration
• Intestinal knockout: Systemic copper deficiency
• Brain-specific: Cognitive deficits

Biomarkers

ATP7A-related biomarkers:

• Serum Copper: Decreased in Menkes disease
• Ceruloplasmin: Reduced activity
• Hair Copper: Low levels
• CSF Copper: May be altered in neurodegeneration

Cross-Pathway Interactions

ATP7A interacts with:

• Metal Metabolism: Central copper homeostasis
• Mitochondrial Function: Cytochrome c oxidase maturation
• Oxidative Stress Response: SOD1 activation
• BBB Integrity: Endothelial copper transport
• Neuroinflammation: Copper's immunomodulatory effects
• [[Metal Metabolism in Neurodegeneration](/mechanisms/metal-metabolism)](/proteins/met)
• [[Blood-Brain Barrier](/mechanisms/blood-brain-barrier)](/genes/ar)
• [[Oxidative Stress](/mechanisms/oxidative-stress-neurodegeneration)](/diseases/neurodegeneration)
• [[Menkes Disease](/diseases/menkes-disease)](/diseases/menkes-disease)
• [[Alzheimer's Disease](/diseases/alzheimers-disease)](/diseases/alzheimers-disease)
• [[ATP7B Gene](/genes/atp7b)](/genes/atp7b)

Background

The study of Atp7A 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

• [PubMed](https://pubmed.ncbi.nlm.nih.gov/) - Biomedical literature
• [Alzheimer's Disease Neuroimaging Initiative](https://adni.loni.usc.edu/) - Research data
• [Allen Brain Atlas](https://brain-map.org/) - Brain gene expression data

References

Lutsenko S, et al, (2007) (2007)

Vulpe C, et al, (1993) (1993)

Kodama H, et al, (2019) (2019)

Nobuta H, et al, (2019) (2019)

White C, et al, (2020) (2020)

Davies KM, et al, (2013) (2013)

Unknown, Bertini I, Rosato A (2008). "Menkes disease." Cell and Tissue Research. 332(3):331-340 (2008)

Unknown, Kaler SG (2011). "ATP7A-related copper transport diseases." Handbook of Clinical Neurology. 105:343-366 (2011)

Pathway Diagram

The following diagram shows the key molecular relationships involving ATP7A discovered through SciDEX knowledge graph analysis: