Atp7B Protein Copper Transporting Atpase 2 plays an important role in the study of neurodegenerative diseases. This page provides comprehensive information about this topic, including its mechanisms, significance in disease processes, and therapeutic implications.
ATP7B (Copper-Transporting ATPase 2) is a critical copper-transporting P-type ATPase encoded by the ATP7B gene on chromosome 13q14.3. It plays an essential role in copper homeostasis, primarily in hepatocytes but also in neurons and other tissues. Mutations in ATP7B cause Wilson's disease (WD), a autosomal recessive disorder characterized by toxic copper accumulation in the liver, brain, and cornea. Understanding ATP7B function is crucial for neurodegenerative disease research, as copper dysregulation is implicated in Alzheimer's disease, Parkinson's disease, and other neurodegenerative conditions.
| Copper-transporting ATPase 2 | |
|---|---|
| Protein Name | Copper-transporting ATPase 2 (Wilson disease protein) |
| Gene | ATP7B |
| UniProt ID | P35602 |
| PDB IDs | 2RCI, 3O0T, 4BMG |
| Molecular Weight | 165 kDa (1465 amino acids) |
| Subcellular Localization | Trans-Golgi network, cytoplasmic vesicles, canalicular membrane |
| Protein Family | P-type ATPase (copper-transporting) family |
ATP7B is a P-type ATPase with complex domain architecture:
| Domain | Position | Function |
|---|---|---|
| N-terminal metal-binding domain (MBD) | 1-333 | 6 copper-binding sites (MXHCX5C motifs) |
| Phosphorylation domain | 648-790 | ATP phosphorylation site (DKTGTLT) |
| ATP-binding domain (P-domain) | 900-1050 | Nucleotide binding |
| Actuator domain (A-domain) | 1100-1250 | Conformational changes |
| Transmembrane domain | 1048-1465 | 8 helices forming channel |
Each MBD can bind one Cu⁺ ion via:
In hepatocytes, ATP7B performs critical functions:
In neurons, ATP7B maintains copper homeostasis:
Copper uptake (CTR1) → Chaperone delivery → ATP7A/ATP7B →
→ Ceruloplasmin (secretion) OR Biliary excretion (ATP7B)
ATP7B mutations cause Wilson's disease with estimated prevalence of 1:30,000:
Hepatic manifestations:
Neurological manifestations:
Psychiatric manifestations:
Other features:
ATP7B connections to AD include:
| Approach | Mechanism | Examples |
|---|---|---|
| Chelation therapy | Bind and excrete copper | Penicillamine, Trientine |
| Zinc salts | Block intestinal copper absorption | Zinc acetate, Zinc sulfate |
| Dietary restriction | Reduce copper intake | Low-copper diet |
| Liver transplantation | Replace defective protein | Orthotopic liver transplant |
| Test | Finding | Significance |
|---|---|---|
| Ceruloplasmin | Low (<20 mg/dL) | Sensitivity 85% |
| 24-hour urinary copper | Elevated (>100 μg) | Highly specific |
| Serum copper | Variable | Not diagnostic alone |
| Liver copper | Elevated (>250 μg/g) | Gold standard |
| MRI brain | T2 hyperintensities | Basal ganglia, thalamus |
Atp7B Protein Copper Transporting Atpase 2 plays an important role in the study of neurodegenerative diseases. This page provides comprehensive information about this topic, including its mechanisms, significance in disease processes, and therapeutic implications.
The study of Atp7B Protein Copper Transporting Atpase 2 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.