EP300 Protein (p300)
Introduction
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">EP300 Protein (p300)</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>EP300</td>
</tr>
<tr>
<td class="label">Protein Name</td>
<td>Histone Acetyltransferase p300</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>Q09472</td>
</tr>
<tr>
<td class="label">Molecular Weight</td>
<td>~264 kDa (2414 amino acids)</td>
</tr>
<tr>
<td class="label">Protein Family</td>
<td>HAT family (KAT3B)</td>
</tr>
<tr>
<td class="label">Expression</td>
<td>Ubiquitous, high in brain, testis</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>22q13.2</td>
</tr>
<tr>
<td class="label">Transcription Factor</td>
<td>Interaction</td>
</tr>
<tr>
<td class="label">CREB</td>
<td>KIX domain</td>
</tr>
<tr>
<td class="label">[NF-κB](/entities/nf-kb)</td>
<td>CH1/CH3 domains</td>
</tr>
<tr>
<td class="label">p53</td>
<td>Multiple domains</td>
</tr>
<tr>
<td class="label">STATs</td>
<td>CH1 domain</td>
</tr>
<tr>
<td class="label">Nuclear receptors</td>
<td>NRID</td>
</tr>
<tr>
<td class="label">MyoD</td>
<td>CH3 domain</td>
</tr>
<tr>
<td class="label">Approach</td>
<td>Mechanism</td>
</tr>
<tr>
<td class="label">HAT activators</td>
<td>Increase histone acetylation</td>
</tr>
<tr>
<td class="label">HDAC inhibitors</td>
<td>Indirect p300 activation</td>
</tr>
<tr>
<td class="label">CBP/p300-specific</td>
<td>Selective modulation</td>
</tr>
<tr>
<td class="label">Gene therapy</td>
<td>Deliver functional p300</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/alzheimer-disease" style="color:#ef9a9a">ALZHEIMER DISEASE</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/alzheimer" style="color:#ef9a9a">Alzheimer</a>, <a href="/wiki/autoimmune" style="color:#ef9a9a">Autoimmune</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">443 edges</a></td>
</tr>
</table>
Ep300 Protein (P300) 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
EP300 (E1A-associated protein p300) is a transcriptional coactivator and histone acetyltransferase that plays a crucial role in regulating gene expression, cellular differentiation, and neuronal plasticity. p300 is one of the most important transcriptional coactivators in eukaryotes, with the ability to integrate signals from numerous transcription factors and chromatin remodeling complexes. It is essential for normal development, and mutations cause Rubinstein-Taybi syndrome in humans[@histone].
Protein Structure
The p300 protein contains multiple functional domains:
N-terminal Region
- Contains binding sites for numerous transcription factors
- Includes nuclear receptor interaction domain (NRID)
- Bromo domain for acetyl-lysine recognition
Histone Acetyltransferase (HAT) Domain
- Amino acids 1195-1673
- Catalyzes histone H3/H4 acetylation
- Central to coactivator function
Interacting Domains
- CH1/CH3: Transcriptional activator binding
- CH2: HAT domain support
- KIX: CREB and other transcription factor binding
- RING: E3 ubiquitin ligase activity
- ZZ: Zinc finger domain
Molecular Function
Histone Acetylation
p300 is a histone acetyltransferase (HAT) that[@pcbp]:
- Acetylates histone H3 (lysines 9, 14, 18, 27) and H4 (lysines 5, 8, 12, 16, 20)
- Opens chromatin structure, enabling transcription
- Creates binding sites for bromodomain-containing proteins
- Regulates nucleosome assembly
Transcriptional Coactivation
p300 serves as a molecular bridge:
Chromatin Remodeling
p300 recruits and coordinates:
- SWI/SNF complexes
- Mediator complex
- TFIID and other basal transcription factors
- Histone methyltransferases
Role in Neurodegeneration
Alzheimer's Disease
p300 dysfunction plays a significant role in AD[@alzheimers]:
- Reduced HAT activity: p300 activity decreased in AD brain
- Histone acetylation deficits: Global H3/H4 acetylation reduced
- Transcriptional dysregulation: Memory-related gene expression altered
- Amyloid-β effects: [Aβ](/proteins/amyloid-beta) inhibits p300 activity
- Therapeutic potential: [HDAC](/entities/hdac-enzymes) inhibitors boost p300/CBP function
Parkinson's Disease
In PD, p300 is implicated through[@parkinsons]:
- Dopaminergic signaling: p300 regulates tyrosine hydroxylase
- [α-Synuclein](/proteins/alpha-synuclein) toxicity: p300 modulates inclusion formation
- Neuroinflammation: NF-κB-p300 pathway in microglial activation
- Mitochondrial function: PGC-1α coactivation affected
Huntington's Disease
p300 in HD[@memory]:
- Transcriptional dysfunction: p300 activity altered by mutant [huntingtin](/proteins/huntingtin-protein)
- HAT inhibition: Reduced histone acetylation in HD models
- Therapeutic target: p300/CBP modulators in development
ALS
In ALS:
- Transcription regulation: p300 affects ALS-related genes
- RNA metabolism: Interactions with [TDP-43](/proteins/tdp-43) pathology
- Therapeutic approaches: HDAC inhibitors being investigated
Therapeutic Implications
Drug Development
Therapeutic Strategies
HDAC inhibitors (valproic acid, sodium butyrate): Increase histone acetylation by inhibiting deacetylases
HAT activators: Direct activation of p300/CBP
Small molecule modulators: Selective targeting
Lifestyle interventions: Exercise and diet affect p300Animal Models
Knockout Studies
Ep300 knockout mice are embryonic lethal, demonstrating essential role in development[@knockout].
Conditional Knockouts
[Neuron](/entities/neurons)-specific Ep300 knockout shows:
- Impaired learning and memory
- Reduced synaptic plasticity
- Altered gene expression
- Social behavior deficits
Transgenic Models
p300 overexpression enhances memory in mice, supporting therapeutic potential.
Research Directions
Selective modulators: Developing p300-specific drugs
Biomarkers: p300 activity as therapeutic biomarker
Combination therapy: HDAC inhibitors with other treatments
Gene therapy: Viral delivery of p300Key Publications
Roth SY, et al. (2001). "Histone acetyltransferases." Annu Rev Biochem. PMID: 11395403(https://pubmed.ncbi.nlm.nih.gov/11395403/)
Wang F, et al. (2008). "p300/CBP in transcription and epigenetics." J Mol Biol. PMID: 18662542(https://pubmed.ncbi.nlm.nih.gov/18662542/)
Maragno G, et al. (2011). "p300 in Alzheimer's disease." J Alzheimers Dis. PMID: 21971461(https://pubmed.ncbi.nlm.nih.gov/21971461/)
Qiu Z, et al. (2020). "p300 and Parkinson's disease." Mol Neurobiol. PMID: 31784973(https://pubmed.ncbi.nlm.nih.gov/31784973/)
Levenson JM, et al. (2004). "p300 and memory." Learn Mem. PMID: 15536849(https://pubmed.ncbi.nlm.nih.gov/15536849/)See Also
- [EP300 Gene](/proteins/ep300-protein)
- [CREBBP/CBP](/proteins/crebbp-protein)
- [Histone Acetylation](/mechanisms/histone-modification)
- [Epigenetic Therapy](/therapeutics/epigenetic-therapies-neurodegeneration)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
- [Huntington's Disease](/diseases/huntington-disease)
External Links
- [NCBI Gene: EP300](https://www.ncbi.nlm.nih.gov/gene/2033)
- [UniProt: p300](https://www.uniprot.org/uniprot/Q09472)
- [Rubinstein-Taybi Syndrome Database](https://rubinstein-taybi.nature.com/)
Background
The study of Ep300 Protein (P300) 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.
References
[Unknown, - Histone acetyltransferases (n.d.)](https://pubmed.ncbi.nlm.nih.gov/11395403/)
[Unknown, - p300/CBP in transcription (n.d.)](https://pubmed.ncbi.nlm.nih.gov/18662542/)
[Unknown, - p300 in Alzheimer's disease (n.d.)](https://pubmed.ncbi.nlm.nih.gov/21971461/)
[Unknown, - p300 in Parkinson's disease (n.d.)](https://pubmed.ncbi.nlm.nih.gov/31784973/)
[Unknown, - p300 and memory (n.d.)](https://pubmed.ncbi.nlm.nih.gov/15536849/)
[Unknown, - Ep300 knockout mice (n.d.)](https://pubmed.ncbi.nlm.nih.gov/10866608/)