GADD45G — Growth Arrest And DNA Damage Inducible Gamma

GADD45G — Growth Arrest And DNA Damage Inducible Gamma

Gene Overview

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">GADD45G — Growth Arrest And DNA Damage Inducible Gamma</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>GADD45G</td>
</tr>
<tr>
<td class="label">Gene Name</td>
<td>Growth Arrest and DNA Damage Inducible Gamma</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>9q22.2</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>[5154](https://www.ncbi.nlm.nih.gov/gene/5154)</td>
</tr>
<tr>
<td class="label">OMIM</td>
<td>[604949](https://www.omim.org/entry/604949)</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>[ENSG00000171846](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000171846)</td>
</tr>
<tr>
<td class="label">UniProt</td>
<td>[O75217](https://www.uniprot.org/uniprot/O75217)</td>
</tr>
<tr>
<td class="label">Protein Length</td>
<td>165 amino acids</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>~18 kDa</td>
</tr>
<tr>
<td class="label">Brain Region</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">Hippocampus</td>
<td>High</td>
</tr>
<tr>
<td class="label">Cortex</td>
<td>High</td>
</tr>
<tr>
<td class="label">Cerebellum</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Substantia nigra</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Striatu

GADD45G — Growth Arrest And DNA Damage Inducible Gamma

Gene Overview

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">GADD45G — Growth Arrest And DNA Damage Inducible Gamma</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>GADD45G</td>
</tr>
<tr>
<td class="label">Gene Name</td>
<td>Growth Arrest and DNA Damage Inducible Gamma</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>9q22.2</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>[5154](https://www.ncbi.nlm.nih.gov/gene/5154)</td>
</tr>
<tr>
<td class="label">OMIM</td>
<td>[604949](https://www.omim.org/entry/604949)</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>[ENSG00000171846](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000171846)</td>
</tr>
<tr>
<td class="label">UniProt</td>
<td>[O75217](https://www.uniprot.org/uniprot/O75217)</td>
</tr>
<tr>
<td class="label">Protein Length</td>
<td>165 amino acids</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>~18 kDa</td>
</tr>
<tr>
<td class="label">Brain Region</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">Hippocampus</td>
<td>High</td>
</tr>
<tr>
<td class="label">Cortex</td>
<td>High</td>
</tr>
<tr>
<td class="label">Cerebellum</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Substantia nigra</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Striatum</td>
<td>Moderate</td>
</tr>
<tr>
<td class="label">Brainstem</td>
<td>Low</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Interaction Type</td>
</tr>
<tr>
<td class="label">PCNA</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">p21^Cip1^</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">MAP3K4</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">p38 MAPK</td>
<td>Indirect</td>
</tr>
<tr>
<td class="label">JNK</td>
<td>Indirect</td>
</tr>
<tr>
<td class="label">Cdc2</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">Topo I</td>
<td>Direct binding</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/alzheimer" style="color:#ef9a9a">Alzheimer</a>, <a href="/wiki/alzheimer's-disease" style="color:#ef9a9a">Alzheimer's Disease</a>, <a href="/wiki/depression" style="color:#ef9a9a">Depression</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a>, <a href="/wiki/neurodegeneration" style="color:#ef9a9a">Neurodegeneration</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">50 edges</a></td>
</tr>
</table>

GADD45G (Growth Arrest and DNA Damage Inducible Gamma) is a member of the GADD45 family of stress-responsive genes, which also includes [GADD45A](/genes/gadd45a) and [GADD45B](/genes/gadd45b). These genes encode small, acidic proteins that function as stress sensors and are induced by various forms of cellular stress including DNA damage, oxidative stress, endoplasmic reticulum (ER) stress, and inflammatory signals. In the brain, GADD45G plays critical roles in neuronal development, synaptic plasticity, and the response to neurotoxic insults. Dysregulated GADD45G expression has been implicated in the pathogenesis of Alzheimer's disease, Parkinson's disease, and other neurodegenerative conditions.

Basic Gene Information

Structure and Function

Protein Structure

GADD45G is a small, highly acidic protein (pI ~4.5) belonging to the GADD45 family. The protein lacks classical signal peptides or transmembrane domains, indicating a cytoplasmic and nuclear localization.

Structural Features

Key Functions

GADD45G participates in multiple cellular processes:

Cell Cycle Arrest

• Induces G1/S and G2/M cell cycle checkpoints in response to DNA damage
• Interacts with p21^Cip1^ to inhibit cyclin-dependent kinases
• Prevents progression through damaged cell cycle checkpoints

DNA Repair

• Promotes DNA base excision repair
• Interacts with PCNA to facilitate repair complex assembly
• Involved in nucleotide excision repair pathways

Apoptosis Regulation

• Can promote or inhibit [apoptosis](/entities/apoptosis) depending on context
• Interacts with mitochondrial apoptosis pathways
• Regulates caspase activation and execution

Stress-Activated Signaling

• Interacts with MAP3K4 and other stress-activated kinases
• Modulates JNK and p38 MAPK signaling pathways
• Integrates cellular stress signals into adaptive responses

Normal Physiological Functions

Neuronal Development

GADD45G plays essential roles in brain development:

Neurogenesis

• Regulates neural progenitor cell proliferation and differentiation
• Controls cell cycle exit during neuronal maturation
• Supports proper brain development

Neuronal Differentiation

• Promotes expression of neuronal differentiation markers
• Coordinates morphological changes during neuron maturation
• Supports axon guidance and dendrite formation

Axon Growth and Regeneration

• Promotes axon regeneration in damaged neurons
• Supports neurite outgrowth in developing neurons
• Enhances axonal plasticity in response to injury

Synaptic Function

GADD45G is involved in synaptic plasticity and function:

Long-Term Potentiation (LTP)

• Required for LTP in hippocampal neurons
• Regulates AMPA receptor trafficking
• Controls synaptic strength and plasticity

Memory Formation

• Essential for memory consolidation
• Supports activity-dependent gene expression
• Contributes to synaptic remodeling during learning

Synaptic Stability

• Maintains synaptic structure and function
• Protects against synaptic degeneration
• Supports dendritic spine morphology

Stress Response in Neurons

GADD45G functions as a stress sensor in neurons:

Oxidative Stress Response

• Activated by reactive oxygen species (ROS)
• Promotes expression of antioxidant genes
• Protects neurons from oxidative damage

DNA Damage Response

• Recognizes DNA lesions in post-mitotic neurons
• Initiates repair programs for damaged DNA
• Prevents accumulation of mutations

ER Stress Response

• Participates in the unfolded protein response (UPR)
• Regulates pro-survival and pro-apoptotic pathways
• Impacts protein quality control mechanisms

Role in Neurodegenerative Diseases

Alzheimer's Disease

GADD45G is implicated in multiple aspects of Alzheimer's disease pathogenesis:

Amyloid-Beta Toxicity

• GADD45G expression is altered in response to amyloid-beta exposure
• Contributes to amyloid-beta-induced neuronal death
• Regulates clearance pathways for amyloid-beta

Tau Pathology

• Modulates tau phosphorylation through regulation of stress kinases
• Influences tau aggregation and toxicity
• Impacts tau-mediated synaptic dysfunction

Synaptic Dysfunction

• Altered GADD45G expression correlates with synaptic loss
• Contributes to memory deficits in AD models
• Regulates AMPA receptor trafficking abnormalities

Neuronal Apoptosis

• GADD45G promotes neuronal apoptosis in AD
• Mediates caspase-dependent cell death pathways
• Contributes to progressive neuronal loss

Parkinson's Disease

GADD45G plays complex roles in Parkinson's disease:

Alpha-Synuclein Toxicity

• GADD45G expression is modulated by alpha-synuclein aggregation
• Contributes to neuronal vulnerability to alpha-synuclein
• Regulates clearance mechanisms for protein aggregates

Mitochondrial Dysfunction

• GADD45G responds to mitochondrial stress
• Modulates mitochondrial quality control pathways
• Affects dopaminergic neuron survival

ER Stress

• Activated by ER stress in PD models
• Contributes to dopaminergic neuron death
• Regulates the UPR in PD pathology

Neuroinflammation

• GADD45G regulates inflammatory responses in microglia
• Modulates cytokine expression in the brain
• Influences neuroinflammation-driven neurodegeneration

Other Neurodegenerative Conditions

Amyotrophic Lateral Sclerosis (ALS)

• GADD45G is upregulated in ALS models and patient tissue
• Contributes to motor neuron death
• Regulates stress response pathways

Huntington's Disease

• Altered GADD45G expression in HD models
• Contributes to neuronal dysfunction
• Modifies disease progression

Stroke and Brain Ischemia

• GADD45G is strongly induced by ischemic injury
• Mediates both protective and damaging responses
• Affects post-ischemic recovery

Signaling Pathways

MAPK Signaling

GADD45G interacts with multiple MAP kinase pathways:

p38 MAPK Pathway

• GADD45G can activate p38 MAPK signaling
• Mediates stress-induced apoptosis
• Regulates inflammatory responses

JNK Pathway

• GADD45G modulates JNK activation
• Influences stress-activated cell death
• Controls neuronal survival decisions

ERK Pathway

• Can inhibit ERK signaling in certain contexts
• Affects cell proliferation and differentiation
• Modulates synaptic plasticity

Cell Cycle Regulation

GADD45G intersects with cell cycle machinery:

• Inhibits CDK activity through p21 interaction
• Blocks cell cycle progression at checkpoints
• Prevents inappropriate cell division in neurons

Apoptosis Pathways

GADD45G modulates both intrinsic and extrinsic apoptosis:

Intrinsic (Mitochondrial) Pathway

• Regulates Bcl-2 family protein function
• Promotes cytochrome c release
• Activates caspase cascade

Extrinsic (Death Receptor) Pathway

• Modulates Fas/TNFR signaling
• Influences death receptor activation
• Regulates downstream caspase execution

DNA Repair Pathways

GADD45G supports DNA repair mechanisms:

• Promotes base excision repair
• Facilitates nucleotide excision repair
• Recruits repair proteins to damaged sites

Expression Pattern in the Brain

GADD45G exhibits region-specific and cell-type-specific expression:

Expression is particularly high in hippocampal CA1 pyramidal neurons and cortical layer 5 pyramidal neurons, which are vulnerable in Alzheimer's disease. In Parkinson's disease, moderate expression in substantia nigra pars compacta dopaminergic neurons is relevant to disease pathogenesis.

Interaction Network

Protein-Protein Interactions

GADD45G interacts with numerous proteins:

Transcriptional Targets

GADD45G regulates expression of various genes:

• Cell cycle regulators: [CDKN1A](/genes/cdkn1a), CDC2
• DNA repair genes: [PCNA](/genes/pcna), [GADD45A](/genes/gadd45a)
• Apoptosis regulators: [BAX](/genes/bax), [BCL2](/genes/bcl2)
• Stress response genes: [HSP70](/genes/hsp70)

Therapeutic Implications

Neuroprotective Strategies

Modulating GADD45G represents a therapeutic target:

Small Molecule Modulators

• Compounds targeting GADD45G expression are under development
• Strategies to normalize GADD45G dysregulation in disease
• Combination approaches with other neuroprotective agents

Gene Therapy Approaches

• Viral vector-mediated GADD45G modulation
• Targeting specific neuronal populations
• Regulated expression systems for safety

Biomarker Potential

GADD45G expression may serve as a biomarker:

• Cerebrospinal fluid GADD45G levels in neurodegeneration
• Peripheral blood mononuclear cell expression
• Correlation with disease progression

Research Methods

Studying GADD45G in Neurodegeneration

Key experimental approaches include:

Summary

GADD45G is a critical stress-responsive gene with complex roles in neuronal function and disease. Its functions span cell cycle regulation, DNA repair, apoptosis, and synaptic plasticity—all processes central to neurodegeneration. While GADD45G can protect neurons from stress, dysregulated expression contributes to pathological processes in Alzheimer's disease, Parkinson's disease, and other conditions. Understanding the dual nature of GADD45G function in different contexts will be essential for developing targeted therapeutic approaches.

See Also

• [GADD45A](/genes/gadd45a) - Related family member involved in DNA damage response
• [GADD45B](/genes/gadd45b) - Related family member in neuronal function
• [Apoptosis Mechanisms](/entities/apoptosis)
• [DNA Repair Pathways](/mechanisms/dna-repair)
• [Cellular Stress Response](/mechanisms/cellular-stress-response)
• [ER Stress Response](/mechanisms/endoplasmic-reticulum-stress)
• [Autophagy Mechanisms](/mechanisms/autophagy)

External Links

• [NCBI Gene: GADD45G](https://www.ncbi.nlm.nih.gov/gene/5154)
• [UniProt: O75217](https://www.uniprot.org/uniprot/O75217)
• [Ensembl: ENSG00000171846](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000171846)
• [PubMed: GADD45G neurodegeneration](https://pubmed.ncbi.nlm.nih.gov/?term=GADD45G+neurodegeneration)

References

Pathway Diagram

The following diagram shows the key molecular relationships involving GADD45G — Growth Arrest And DNA Damage Inducible Gamma discovered through SciDEX knowledge graph analysis:

Disease Associations

Source: Open Targets Platform (opentargets.org)

| Disease | Association Score | Disease ID |
|--------|-------------------|------------|
| neurodegenerative disease | 0.5266 | EFO_0005772 |
| asthma | 0.4825 | MONDO_0004979 |
| mathematical ability | 0.4724 | EFO_0004875 |
| intelligence | 0.4221 | EFO_0004337 |
| cleft lip | 0.3316 | EFO_0003959 |