SFPQ Gene

SFPQ — Splicing Factor Proline and Glutamine Rich

<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">SFPQ</th></tr> [@co2018]
<tr><td><strong>Gene Symbol</strong></td><td>SFPQ</td></tr> [@ito2016]
<tr><td><strong>Full Name</strong></td><td>Splicing Factor Proline and Glutamine Rich</td></tr> [@kwong2018]
<tr><td><strong>Chromosome</strong></td><td>1p35.3</td></tr> [@buratti2021]
<tr><td><strong>NCBI Gene ID</strong></td><td>[6736](https://www.ncbi.nlm.nih.gov/gene/6736)</td></tr> [@dreyfuss2020]
<tr><td><strong>OMIM</strong></td><td>605199</td></tr> [@zhao2022]
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000116560</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P23246](https://www.uniprot.org/uniprot/P23246)</td></tr>
<tr><td><strong>Protein Type</strong></td><td>RNA-binding protein, Splicing factor</td></tr>
<tr><td><strong>Cellular Location</strong></td><td>Nuclear speckles, Nucleus</td></tr>
<tr><td><strong>Brain Expression</strong></td><td>Motor [neurons](/entities/neurons), Cortical neurons, Hippocampus</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/carcinoma" style="color:#ef9a9a">Carcinoma</a>, <a href="/wiki/hepatitis" style="color:#ef9a9a">Hepatitis</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">10 edges</a></td>
</tr>
</tab

SFPQ — Splicing Factor Proline and Glutamine Rich

<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">SFPQ</th></tr> [@co2018]
<tr><td><strong>Gene Symbol</strong></td><td>SFPQ</td></tr> [@ito2016]
<tr><td><strong>Full Name</strong></td><td>Splicing Factor Proline and Glutamine Rich</td></tr> [@kwong2018]
<tr><td><strong>Chromosome</strong></td><td>1p35.3</td></tr> [@buratti2021]
<tr><td><strong>NCBI Gene ID</strong></td><td>[6736](https://www.ncbi.nlm.nih.gov/gene/6736)</td></tr> [@dreyfuss2020]
<tr><td><strong>OMIM</strong></td><td>605199</td></tr> [@zhao2022]
<tr><td><strong>Ensembl ID</strong></td><td>ENSG00000116560</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[P23246](https://www.uniprot.org/uniprot/P23246)</td></tr>
<tr><td><strong>Protein Type</strong></td><td>RNA-binding protein, Splicing factor</td></tr>
<tr><td><strong>Cellular Location</strong></td><td>Nuclear speckles, Nucleus</td></tr>
<tr><td><strong>Brain Expression</strong></td><td>Motor [neurons](/entities/neurons), Cortical neurons, Hippocampus</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/carcinoma" style="color:#ef9a9a">Carcinoma</a>, <a href="/wiki/hepatitis" style="color:#ef9a9a">Hepatitis</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">10 edges</a></td>
</tr>
</table>
</div>

Introduction

SFPQ (Splicing Factor Proline and Glutamine Rich) encodes a nuclear RNA-binding protein that functions as a critical regulator of alternative splicing, transcriptional regulation, and RNA processing. As a member of the Drosophila behavior-splicing factor family (and paralalog of NONO and PSPC1), SFPQ acts as a molecular scaffold, forming complexes with other splicing factors to regulate gene expression at multiple levels. Dysfunction of SFPQ has been strongly implicated in neurodegenerative diseases, particularly amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), where mutations disrupt RNA splicing and processing essential for motor neuron survival.

Overview

SFPQ is a ubiquitously expressed nuclear protein with particularly high expression in the brain, especially in motor neurons, cortical neurons, and the [hippocampus](/brain-regions/hippocampus). The protein localizes to nuclear speckles, which are subnuclear compartments involved in RNA splicing and processing. SFPQ functions as a key regulator of neuronal RNA metabolism, controlling the alternative splicing of genes critical for neuronal survival, synaptic function, and axonal transport.

Mutations in SFPQ have been identified in patients with amyotrophic lateral sclerosis and frontotemporal dementia, linking RNA metabolism defects to these devastating neurodegenerative conditions. The discovery of SFPQ mutations in ALS/FTD has highlighted the importance of RNA processing in motor neuron health and has opened new avenues for understanding disease mechanisms.

Protein Structure and Function

Domain Architecture

SFPQ contains several functional domains:

• N-terminal domain: Contains multiple proline-rich motifs that mediate protein-protein interactions
• RNA recognition motif (RRM) domains: Two RRM domains that bind RNA and single-stranded DNA
• C-terminal domain: Involved in multimerization and complex formation

Molecular Functions

SFPQ performs several critical cellular functions:

Protein Complexes

SFPQ forms heterodimeric and multimeric complexes with:

• NONO: Paralogous protein forming SFPQ-NONO complexes involved in diverse nuclear functions
• PSPC1: Another paralog involved in RNA processing
• Other splicing factors: Including hnRNPs and U2AF components

Expression and Localization

Brain Expression Pattern

SFPQ exhibits high expression in the nervous system:

| Brain Region | Expression Level | Cell Types |
|--------------|-----------------|------------|
| Motor [Cortex](/brain-regions/cortex) | High | Upper motor neurons, Interneurons |
| Spinal Cord | Very High | Lower motor neurons |
| Hippocampus | High | CA1-CA3 pyramidal neurons, Dentate gyrus |
| Frontal Cortex | High | Cortical pyramidal neurons |
| Basal Ganglia | Moderate | Medium spiny neurons |
| Cerebellum | Moderate | Purkinje cells, Granule cells |

Subcellular Localization

• Primary location: Nuclear speckles (speckled nuclear domains)
• Nucleoplasm: Diffuse nuclear distribution
• Cytoplasmic: Transient cytoplasmic localization during stress granule formation

Role in Neurodegeneration

Amyotrophic Lateral Sclerosis

SFPQ mutations are associated with familial amyotrophic lateral sclerosis (ALS) through several mechanisms:

• Disrupted RNA processing: Mutations such as P335L, G471R, and M114T impair SFPQ's ability to regulate alternative splicing of genes critical for motor neuron survival
• Splicing defects: Aberrant splicing of transcripts involved in cytoskeletal function, axonal transport, and mitochondrial function
• Stress granule dysfunction: Altered stress granule dynamics leading to impaired RNA metabolism under cellular stress
• DNA damage accumulation: Impaired DNA damage repair contributing to neuronal vulnerability

Frontotemporal Dementia

SFPQ mutations also cause frontotemporal dementia (FTD), often with overlapping clinical features with ALS:

• RNA metabolism dysregulation: Similar to ALS, FTD-associated mutations disrupt normal RNA processing
• [TDP-43](/mechanisms/tdp-43-proteinopathy) pathology: Interactions between SFPQ dysfunction and TDP-43 proteinopathy
• Neuronal nuclear dysfunction: Nuclear speckle disruption and impaired nuclear RNA processing

Alzheimer's Disease

While less strongly associated than ALS/FTD, SFPQ dysfunction may contribute to Alzheimer disease through:

• Alternative splicing defects: Dysregulated splicing of [tau](/proteins/tau) and [amyloid precursor protein](/entities/app-protein) (APP) transcripts
• Synaptic RNA processing: Impaired regulation of synaptic protein transcripts
• DNA damage accumulation: Contributing to neuronal senescence

Parkinson's Disease

Emerging evidence links SFPQ to Parkinson disease pathogenesis:

• Alpha-synuclein interaction: Potential interactions with [alpha-synuclein](/proteins/alpha-synuclein) pathology
• Mitochondrial RNA processing: Impaired processing of mitochondrial transcripts
• Dopaminergic neuron vulnerability: Motor neuron-like vulnerability in dopaminergic neurons

Pathogenic Mechanisms

RNA Splicing Dysregulation

SFPQ mutations lead to widespread changes in alternative splicing:

Transcriptional Dysregulation

SFPQ dysfunction affects transcription of:

• Neuronal survival genes
• Synaptic protein genes
• Axonal transport genes
• Mitochondrial function genes

Stress Granule Pathology

SFPQ is involved in stress granule formation:

• Altered stress granule dynamics in mutant SFPQ
• Sequestration of RNA and proteins in abnormal granules
• Impaired stress response

Therapeutic Implications

SFPQ represents a promising therapeutic target for ALS and FTD:

RNA-Targeting Therapies

• Antisense oligonucleotides: Designed to modulate SFPQ splicing or expression
• Small molecule splicing modulators: Compounds that restore normal splicing patterns
• RNA delivery: Viral vector-mediated delivery of wild-type SFPQ

Gene Therapy Approaches

• Gene replacement: Restoring functional SFPQ expression
• CRISPR-based therapies: Correcting disease-causing mutations
• Gene silencing: Targeting toxic mutant alleles

Neuroprotective Strategies

• Stress granule modulators: Drugs that normalize stress granule dynamics
• DNA damage repair enhancers: Compounds that boost DNA repair capacity
• Neurotrophic factors: Supporting neuronal survival pathways

Animal Models

Several animal models have been developed to study SFPQ:

• SFPQ knockout mice: Embryonic lethal, demonstrating essential function
• Conditional knockout models: Motor neuron-specific deletion reveals neurodegeneration
• Transgenic models: Expressing human mutant SFPQ
• Knock-in models: Containing patient-specific mutations

Key Publications

Background

The identification of SFPQ mutations in ALS and FTD has highlighted the critical importance of RNA metabolism in neurodegenerative diseases. Prior to these discoveries, TDP-43 and FUS were the major RNA-binding proteins linked to ALS/FTD, and SFPQ represents another key player in this pathway. Research continues to elucidate the precise mechanisms by which SFPQ dysfunction leads to neuronal death and to develop therapeutic interventions targeting this pathway.

External Links

• [PubMed](https://pubmed.ncbi.nlm.nih.gov/?term=SFPQ+ALS+neurodegeneration) - Biomedical literature
• [NCBI Gene](https://www.ncbi.nlm.nih.gov/gene/6736) - Gene database entry
• [UniProt](https://www.uniprot.org/uniprot/P23246) - Protein database entry
• [Allen Brain Atlas](https://human.brain-map.org/) - Brain gene expression data

See Also

• [Amyotrophic Lateral Sclerosis](/diseases/amyotrophic-lateral-sclerosis)
• [Frontotemporal Dementia](/diseases/frontotemporal-dementia)
• NONO Gene
• RNA Splicing in Neurodegeneration
• Stress Granules in ALS

References

Pathway Diagram

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