SYN3 — Synapsin III

SYN3 — Synapsin III

<table class="infobox infobox-gene">
<tr><th class="infobox-header" colspan="2">SYN3 — Synapsin III</th></tr>
<tr><td class="label">Symbol</td><td><strong>SYN3</strong></td></tr>
<tr><td class="label">Full Name</td><td>Synapsin III</td></tr>
<tr><td class="label">Chromosome</td><td>22q12.3</td></tr>
<tr><td class="label">NCBI Gene</td><td><a href="https://www.ncbi.nlm.nih.gov/gene/8864" target="_blank">8864</a></td></tr>
<tr><td class="label">Ensembl</td><td>ENSG00000185608</td></tr>
<tr><td class="label">OMIM</td><td><a href="https://omim.org/entry/600731" target="_blank">600731</a></td></tr>
<tr><td class="label">UniProt</td><td><a href="https://www.uniprot.org/uniprot/O75907" target="_blank">O75907</a></td></tr>
<tr><td class="label">Protein Class</td><td>Synapsin Family</td></tr>
<tr><td class="label">Expression</td><td>Cerebral [cortex](/brain-regions/cortex), [Hippocampus](/brain-regions/hippocampus), Synaptic terminals, Retina</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/depression" style="color:#ef9a9a">Depression</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">14 edges</a></td>
</tr>
</table>

SYN3 — Synapsin III

Introduction

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SYN3 — Synapsin III

<table class="infobox infobox-gene">
<tr><th class="infobox-header" colspan="2">SYN3 — Synapsin III</th></tr>
<tr><td class="label">Symbol</td><td><strong>SYN3</strong></td></tr>
<tr><td class="label">Full Name</td><td>Synapsin III</td></tr>
<tr><td class="label">Chromosome</td><td>22q12.3</td></tr>
<tr><td class="label">NCBI Gene</td><td><a href="https://www.ncbi.nlm.nih.gov/gene/8864" target="_blank">8864</a></td></tr>
<tr><td class="label">Ensembl</td><td>ENSG00000185608</td></tr>
<tr><td class="label">OMIM</td><td><a href="https://omim.org/entry/600731" target="_blank">600731</a></td></tr>
<tr><td class="label">UniProt</td><td><a href="https://www.uniprot.org/uniprot/O75907" target="_blank">O75907</a></td></tr>
<tr><td class="label">Protein Class</td><td>Synapsin Family</td></tr>
<tr><td class="label">Expression</td><td>Cerebral [cortex](/brain-regions/cortex), [Hippocampus](/brain-regions/hippocampus), Synaptic terminals, Retina</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/depression" style="color:#ef9a9a">Depression</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">14 edges</a></td>
</tr>
</table>

SYN3 — Synapsin III

Introduction

Syn3 — Synapsin Iii is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Overview

SYN3 (Synapsin III) is a gene located on chromosome 22q12.3 encoding Synapsin III, a neuronal phosphoprotein associated with synaptic vesicles[@ref]. Synapsin III is the least characterized member of the synapsin family, which also includes SYN1 and SYN2. It plays critical roles in synaptogenesis, synaptic vesicle trafficking, and neurotransmitter release[^2]. The gene is catalogued as NCBI Gene ID 8864.

Gene Overview

| Property | Value |
|----------|-------|
| Gene Symbol | SYN3 |
| Full Name | Synapsin III |
| Chromosomal Location | 22q12.3 |
| NCBI Gene ID | 8864 |
| Ensembl ID | ENSG00000185608 |
| OMIM ID | 600731 |
| UniProt ID | O75907 |
| Protein Length | 580 amino acids |
| Molecular Weight | ~63 kDa |

Protein Structure

Synapsin III contains several functional domains:

• N-terminal domain A: Phosphorylation site for PKA and CaMKII
• Central domain C: ATP-binding site, involved in synaptic vesicle clustering
• C-terminal domain E: Proline-rich region, mediates protein-protein interactions

The protein is associated with the cytoplasmic surface of synaptic vesicles[^3].

Normal Function

Synaptic Vesicle Biology

Synapsin III is involved in:

• Synaptogenesis: Critical for formation and maintenance of synaptic contacts
• Vesicle trafficking: Regulates movement of synaptic vesicles between reserve and active pools
• Neurotransmitter release: Modulates calcium-dependent neurotransmitter release
• Synaptic plasticity: Involved in short-term and long-term synaptic plasticity

Brain Expression

In the brain, SYN3 is expressed in:

• Cerebral cortex: Layer-specific expression in pyramidal [neurons](/entities/neurons)
• Hippocampus: CA1-CA3 regions, dentate gyrus
• Synaptic terminals: Pre-synaptic terminals throughout the brain
• Retina: Photoreceptor synapses and inner retinal layers

Comparison with Other Synapsins

| Property | SYN1 | SYN2 | SYN3 |
|----------|------|------|------|
| Chromosome | X | 3 | 22 |
| Isoforms | 3 | 2 | 1 |
| Brain expression | High | High | Moderate |
| Knockout phenotype | Seizures | Behavioral | Viable |

Disease Associations

Parkinson's Disease

SYN3 has been implicated in Parkinson's disease:

• Genetic associations: SYN3 polymorphisms linked to PD risk
• [Alpha-synuclein](/proteins/alpha-synuclein) interaction: May interact with alpha-synuclein in Lewy body formation
• Synaptic dysfunction: Early synaptic changes in PD models
• Therapeutic target: Modulating SYN3 may protect synapses

Schizophrenia

SYN3 is associated with schizophrenia:

• Genetic variants: SYN3 polymorphisms associated with schizophrenia risk
• Expression changes: Altered SYN3 expression in schizophrenic brains
• Synaptic pathology: Contributes to synaptic deficits in schizophrenia

Other Neurological Conditions

• Epilepsy: Altered synapsin III expression in epileptic tissue
• Autism spectrum disorders: Possible role in synaptic dysfunction
• Depression: Involvement in monoaminergic signaling

Molecular Interactions

SYN3 interacts with:

• Synaptic vesicle proteins: Synaptophysin, Synaptotagmin
• Cytoskeletal proteins: Actin, Tubulin
• Signaling molecules: PKA, CaMKII, MAPK
• Other synapsins: SYN1, SYN2 (hetero-oligomers)

Therapeutic Implications

Biomarkers

• Cerebrospinal fluid: SYN3 levels as synaptic integrity marker
• Blood biomarkers: Peripheral SYN3 as neuronal damage indicator

Therapeutic Targets

• Phosphorylation modulators: Drugs affecting SYN3 phosphorylation state
• Gene therapy: Viral vector delivery of SYN3
• Small molecules: Compounds enhancing SYN3 function

Brain Atlas Resources

• [Allen Brain Atlas: SYN3 expression](https://human.brain-map.org/microarray/search/show?search_term=SYN3)
• [Allen Mouse Brain Atlas: Syn3](https://mouse.brain-map.org/search/index.html?query=Syn3)
• [Allen Cell Type Atlas](https://portal.brain-map.org/atlases-and-data/rnaseq)
• [BrainSpan: Developmental expression](https://www.brainspan.org)

Background

The study of Syn3 — Synapsin Iii 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.

Cross-References

• [Genes Index](/genes)
• [SYN1 — Synapsin I](/genes/syn1)
• [SYN2 — Synapsin II](/genes/syn2)
• [Synaptic Vesicle Proteins](/proteins/synaptophysin)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [Alpha-Synuclein](/proteins/alpha-synuclein)

See Also

• [Genes Index](/genes)
• [Proteins Index](/proteins)
• [Mechanisms Index](/mechanisms)

External Links

• [NCBI Gene: SYN3](https://www.ncbi.nlm.nih.gov/gene/8864)
• [UniProt: O75907](https://www.uniprot.org/uniprot/O75907)
• [OMIM: 600731](https://omim.org/entry/600731)
• [Ensembl: ENSG00000185608](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000185608)

External Links

• [NCBI Gene - ROCK1 (Rho-Associated Coiled-Coil Containing Protein Kinase 1)](https://www.ncbi.nlm.nih.gov/gene/)
• [UniProt - ROCK1 (Rho-Associated Coiled-Coil Containing Protein Kinase 1)](https://www.uniprot.org/uniprot/)
• [GeneCards - ROCK1 (Rho-Associated Coiled-Coil Containing Protein Kinase 1)](https://www.genecards.org/cgi-bin/carddisp.pl?gene=)

References

Unknown, : : (n.d.)

Pathway Diagram

The following diagram shows the key molecular relationships involving SYN3 — Synapsin III discovered through SciDEX knowledge graph analysis: