DDX5 Gene

DDX5 Gene

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">DDX5 — RNA Helicase DDX5 (p68)</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>DDX5</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>DEAD-Box Helicase 5 (p68)</td>
</tr>
<tr>
<td class="label">Chromosome</td>
<td>17q21.31</td>
</tr>
<tr>
<td class="label">NCBI Gene</td>
<td><a href="https://www.ncbi.nlm.nih.gov/gene/1652" target="_blank">1652</a></td>
</tr>
<tr>
<td class="label">Ensembl</td>
<td><a href="https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000108654" target="_blank">ENSG00000108654</a></td>
</tr>
<tr>
<td class="label">OMIM</td>
<td><a href="https://omim.org/entry/180387" target="_blank">180387</a></td>
</tr>
<tr>
<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/P17844" target="_blank">P17844</a></td>
</tr>
<tr>
<td class="label">Protein Class</td>
<td>DEAD-box RNA helicase</td>
</tr>
<tr>
<td class="label">Expression</td>
<td>High in brain (cortex, hippocampus, cerebellum), testis, muscle</td>
</tr>
<tr>
<td class="label">Diseases</td>
<td><a href="/diseases/amyotrophic-lateral-sclerosis">ALS</a>, <a href="/diseases/alzheimers-disease">Alzheimer's Disease</a>, <a href="/diseases/parkinsons-disease">Parkinson's Disease</a>, Spinocerebellar Ataxia</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/al

DDX5 Gene

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">DDX5 — RNA Helicase DDX5 (p68)</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>DDX5</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>DEAD-Box Helicase 5 (p68)</td>
</tr>
<tr>
<td class="label">Chromosome</td>
<td>17q21.31</td>
</tr>
<tr>
<td class="label">NCBI Gene</td>
<td><a href="https://www.ncbi.nlm.nih.gov/gene/1652" target="_blank">1652</a></td>
</tr>
<tr>
<td class="label">Ensembl</td>
<td><a href="https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000108654" target="_blank">ENSG00000108654</a></td>
</tr>
<tr>
<td class="label">OMIM</td>
<td><a href="https://omim.org/entry/180387" target="_blank">180387</a></td>
</tr>
<tr>
<td class="label">UniProt</td>
<td><a href="https://www.uniprot.org/uniprot/P17844" target="_blank">P17844</a></td>
</tr>
<tr>
<td class="label">Protein Class</td>
<td>DEAD-box RNA helicase</td>
</tr>
<tr>
<td class="label">Expression</td>
<td>High in brain (cortex, hippocampus, cerebellum), testis, muscle</td>
</tr>
<tr>
<td class="label">Diseases</td>
<td><a href="/diseases/amyotrophic-lateral-sclerosis">ALS</a>, <a href="/diseases/alzheimers-disease">Alzheimer's Disease</a>, <a href="/diseases/parkinsons-disease">Parkinson's Disease</a>, Spinocerebellar Ataxia</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a>, <a href="/wiki/hepatocellular-carcinoma" style="color:#ef9a9a">Hepatocellular carcinoma</a>, <a href="/wiki/longevity" style="color:#ef9a9a">Longevity</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">47 edges</a></td>
</tr>
</table>

DDX5 — DEAD-Box Helicase 5 (p68)

Overview

DDX5 (DEAD-Box Helicase 5), also known as p68, is a member of the DEAD-box family of RNA helicases. Encoded by the DDX5 gene on chromosome 17q21.31, this protein possesses ATP-dependent RNA helicase activity and participates in various aspects of RNA metabolism including transcription, splicing, ribosome biogenesis, and stress response[@lally2013]. DDX5 functions as both an RNA helicase and a transcriptional coactivator, making it a multifunctional regulator of gene expression.

In [neurons](/entities/neurons), DDX5 plays critical roles in RNA processing, stress granule formation, and synaptic plasticity. Dysregulation of DDX5 has been implicated in several neurodegenerative diseases including [amyotrophic lateral sclerosis](/diseases/amyotrophic-lateral-sclerosis) (ALS), [Alzheimer's disease](/diseases/alzheimers-disease), and [Parkinson's disease](/diseases/parkinsons-disease), where it contributes to RNA granule pathology and protein aggregation[@jiang2018].

Structure

Protein Architecture

DDX5 is a 614-amino acid protein with the characteristic DEAD-box helicase domain structure:

• N-terminal domain (residues 1-250): Contains motifs I (Walker A), II (Walker B/DEAD), III, and IV
• C-terminal domain (residues 250-400): Contains motifs V and VI
• Flanking regions: Regulatory sequences and protein interaction motifs

Conserved Motifs

| Motif | Sequence | Function |
|-------|----------|----------|
| I | AxxGxGKT | ATP binding |
| II | DEAD | ATP hydrolysis |
| III | SAT | Translocase activity |
| IV | QRxGRxGR | RNA binding |
| V | VFEVR | RNA binding |
| VI | HxAR | ATP hydrolysis |

Structural Features

• RecA-like folds: Two domains with helicase core
• Linker region: Flexible connection between domains
• Post-translational modifications: Phosphorylation, acetylation sites

Normal Function

RNA Helicase Activity

DDX5 catalyzes ATP-dependent unwinding of RNA duplexes:

Transcriptional Coactivator

Beyond helicase activity, DDX5 functions as a transcriptional coactivator:

• p53 activation: Enhances p53-mediated transcription
• Estrogen receptor: Coactivator for ERα-dependent transcription
• Runx2: Regulates osteoblast differentiation
• NF-κB: Modulates inflammatory gene expression

RNA Processing Functions

DDX5 participates in multiple RNA processing pathways:

• Alternative splicing: Promotes splicing of specific pre-mRNAs
• RNA stability: Regulates mRNA half-life
• Translation initiation: Modulates translation efficiency
• Ribosome biogenesis: Participates in rRNA processing

Expression and Distribution

Tissue Expression

DDX5 is ubiquitously expressed with highest levels in:

• Brain: [Cortex](/brain-regions/cortex), [hippocampus](/brain-regions/hippocampus), [cerebellum](/brain-regions/cerebellum), substantia nigra
• Testis: Germ cells
• Ovary: Oocytes
• Muscle: Skeletal muscle

Subcellular Localization

• Nucleus: Predominantly nuclear, in nucleolus and speckles
• Cytoplasm: Present in RNA granules and stress granules
• Synapses: Localized to dendritic spines and presynaptic terminals

Role in Neurodegeneration

Amyotrophic Lateral Sclerosis (ALS)

DDX5 is centrally involved in ALS pathogenesis[@hubbard2020]:

Stress Granule Formation

• DDX5 is recruited to stress granules under proteotoxic stress
• Forms cytoplasmic RNA-protein aggregates
• In ALS, these granules become pathological
• Contributes to TDP-43 and FUS pathology

Mechanisms

• RNA metabolism dysregulation: Altered processing of mRNAs
• Protein aggregation: Seeds formation of stress granules
• Transport defects: Impaired RNA granule transport
• Neuronal vulnerability: Motor neurons particularly affected

Alzheimer's Disease

DDX5 dysfunction contributes to AD pathogenesis[@chen2022]:

Evidence

• Altered DDX5 expression in AD brains
• Impaired RNA metabolism in AD neurons
• Links to tau pathology
• Contributions to synaptic dysfunction

Molecular Mechanisms

• Translation dysregulation: Altered protein synthesis
• RNA granule pathology: Stress granule accumulation
• Synaptic RNA processing: Impaired synaptic plasticity
• Cellular stress response: Dysregulated stress responses

Parkinson's Disease

DDX5 is implicated in PD through:

• Altered expression in substantia nigra dopaminergic neurons
• Connections to alpha-synuclein pathology
• RNA metabolism defects
• Mitochondrial stress response

Spinocerebellar Ataxia

DDX5 interacts with ataxin proteins:

• SCA1, SCA2, SCA3 pathogenic proteins interact with DDX5
• Contributes to RNA processing defects
• Participates in neurodegeneration

Therapeutic Targeting

DDX5 as Therapeutic Target

DDX5 represents a potential therapeutic target:

Approaches

Challenges

• Essential normal functions must be preserved
• Delivery to neurons
• Balancing stress granule regulation

Biomarker Potential

DDX5 measurement may serve as biomarker[@zhang2024]:

• Peripheral blood DDX5 levels
• Disease progression correlation
• Therapeutic response monitoring

Genetic Variants

DDX5 Polymorphisms

• Expression variants affecting DDX5 levels
• Coding variants altering function
• Disease-associated risk alleles

Disease Associations

| Condition | Variant Type | Effect |
|-----------|-------------|--------|
| ALS | Risk SNPs | Altered stress granule dynamics |
| AD | Expression variants | Impaired RNA metabolism |
| PD | Risk variants | Dopaminergic vulnerability |

DDX5 in Stress Granule Biology

Stress Granule Formation

Under cellular stress, DDX5 participates in stress granule assembly:

Pathological Implications

In neurodegeneration:

• Stress granules become persistent
• Seed protein aggregation
• Impair cellular function
• Contribute to cell death

Interactions with Other Proteins

RNA-Binding Proteins

DDX5 interacts with:

• TDP-43: RNA-binding protein in ALS/FTD
• FUS: Fused in sarcoma protein
• TIA-1: Stress granule marker
• G3BP1: Stress granule component

Transcription Factors

• p53: Tumor suppressor, stress response
• Estrogen receptor: Nuclear receptor
• Runx2: Development transcription factor

Recent Research Advances (2023-2025)

Mechanistic Insights

• DDX5 interactions with pathological proteins clarified
• Neuronal-specific functions defined
• Stress granule dynamics understood

Therapeutic Development

• DDX5 modulators in development
• ASO approaches being explored
• Biomarker validation ongoing

Research Directions

Unanswered Questions

• What determines DDX5 pathological vs. normal function?
• How does DDX5 contribute to specific neurodegenerative diseases?
• Can DDX5 be safely modulated therapeutically?

Clinical Development

• Biomarker studies
• Therapeutic targeting approaches
• Understanding disease specificity

DDX5 Pathway in Neurodegeneration

Clinical Perspective

Diagnostic Utility

DDX5 measurement offers diagnostic potential:

• Blood DDX5 levels as biomarker
• Stress granule markers
• Disease progression monitoring

Patient Stratification

• DDX5 expression levels guide therapy
• Genetic variants inform risk
• Stress granule burden assessment

Management Guidelines

| Disease | DDX5 Strategy | Development Stage |
|---------|---------------|-------------------|
| ALS | Modulator therapy | Preclinical |
| AD | Biomarker development | Research |
| PD | Target identification | Early |

See Also

• [DDX5 Protein](/proteins/ddx5-protein) — Protein page
• [DDX6](/genes/ddx6) — Related DEAD-box helicase
• [DDX3X](/genes/ddx3x) — Related DEAD-box helicase in stress granules
• [TDP-43](/proteins/tdp-43) — RNA-binding protein in ALS/FTD
• [FUS](/proteins/fus-protein) — Fused in sarcoma protein
• [Stress Granule Pathway](/mechanisms/stress-granule-pathway) — Mechanisms
• [ALS](/diseases/amyotrophic-lateral-sclerosis) — Disease association
• [Alzheimer's Disease](/diseases/alzheimers-disease) — Disease association

External Links

• [NCBI Gene*: [https://www.ncbi.nlm.nih.gov/gene/1652](https://www.ncbi.nlm.nih.gov/gene/1652)](/institutions/nih)
• [Ensembl*: [https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000108654](https://ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000108654)](/genes/ar)
• [UniProt*: [https://www.uniprot.org/uniprot/P17844](https://www.uniprot.org/uniprot/P17844)](/entities/htt)
• [OMIM*: [https://omim.org/entry/180387](https://omim.org/entry/180387)](/entities/htt)

References

Pathway Diagram

The following diagram shows the key molecular relationships involving DDX5 Gene discovered through SciDEX knowledge graph analysis: