Phosphorylated Alpha Synuclein (Pser129) Biomarker is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Phosphorylated alpha-synuclein at Serine 129 (pSer129) is a highly specific pathological form of alpha-synuclein that is predominantly found in Lewy bodies and other synuclein aggregates in neurodegenerative diseases. It serves as a critical biomarker for the diagnosis and tracking of Parkinson's disease, Dementia with Lewy Bodies, and Multiple System Atrophy.
| Property | Value |
|---|---|
| Category | CSF/ tissue Biomarker |
| Target | Alpha-synuclein phosphorylated at Ser129 |
| Sample Type | CSF, brain tissue, blood |
| Diseases | Parkinson's Disease, DLB, MSA, PAF |
| Sensitivity | 85-95% for PD/DLB |
| Specificity | 90-98% for synucleinopathies |
Alpha-synuclein is a 140-amino acid protein encoded by the SNCA gene, predominantly expressed in presynaptic terminals. Under pathological conditions, alpha-synuclein misfolds and aggregates into soluble oligomers and insoluble fibrils that form Lewy bodies and Lewy neurites.
Phosphorylation at serine 129 (pSer129) was first described in 2003 and is now recognized as a major post-translational modification in pathological alpha-synuclein. Approximately 90% of alpha-synuclein in Lewy bodies is phosphorylated at this site.
| Sample Type | Collection | Storage |
|---|---|---|
| CSF | LP, 2nd tube | -80°C |
| Blood | EDTA plasma | -80°C |
| Tissue | Post-mortem | -80°C |
| Marker | What it Measures | Clinical Use |
|---|---|---|
| Total α-syn | All alpha-synuclein | Lower in synucleinopathies |
| pSer129 | Pathological form | Higher in synucleinopathies |
| pSer129/total ratio | Pathological fraction | Most discriminative |
| Disease | Sensitivity | Specificity (vs AD) |
|---|---|---|
| PD | 85-95% | 90-98% |
| DLB | 88-95% | 88-95% |
| MSA | 50-70% | 85-95% |
| AD | 5-10% | — |
| Condition | pSer129 Status |
|---|---|
| Parkinson's Disease | Positive |
| Dementia with Lewy Bodies | Positive |
| Multiple System Atrophy | Often Positive |
| Progressive Supranuclear Palsy | Usually Negative |
| Corticobasal Degeneration | Usually Negative |
| Alzheimer's Disease | Usually Negative |
| Healthy Controls | Negative |
Current research areas include:
pSer129 is a direct target for:
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