NCOA2 Gene

NCOA2 Gene

Gene Overview

<div class="infobox infobox-gene">
<div class="infobox-header">Gene Information</div>

<table>
<tr><th>Symbol</th><td>NCOA2</td></tr>
<tr><th>Full Name</th><td>Nuclear Receptor Coactivator 2</td></tr>
<tr><th>Chromosome</th><td>8q13.3</td></tr>
<tr><th>NCBI Gene ID</th><td>[10499](https://www.ncbi.nlm.nih.gov/gene/10499)</td></tr>
<tr><th>UniProt ID</th><td>[Q15596](https://www.uniprot.org/uniprot/Q15596)</td></tr>
<tr><th>Ensembl ID</th><td>[ENSG00000140396](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000140396)</td></tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>
</div>

Overview

NCOA2 (Nuclear Receptor Coactivator 2), also known as GRIP1 (Glucocorticoid Receptor-Interacting Protein 1) or TIF2 (Transcriptional Intermediary Factor 2), is a transcriptional coactivator that plays a critical role in nuclear receptor-mediated gene transcription. As a member of the p160/SRC (Steroid Receptor Coactivator) family, NCOA2 serves as a bridge between nuclear receptors and the general transcription machinery, amplifying gene expression programs that are essential for neuronal function, synaptic plasticity, and cellular survival [@xu1999][@leo2000].

Function

NCOA2 is a ~175 kDa protein containing multiple functional domains that mediate protein-protein interactions:

Transcriptional Coactivation

NCOA2 Gene

Gene Overview

<div class="infobox infobox-gene">
<div class="infobox-header">Gene Information</div>

<table>
<tr><th>Symbol</th><td>NCOA2</td></tr>
<tr><th>Full Name</th><td>Nuclear Receptor Coactivator 2</td></tr>
<tr><th>Chromosome</th><td>8q13.3</td></tr>
<tr><th>NCBI Gene ID</th><td>[10499](https://www.ncbi.nlm.nih.gov/gene/10499)</td></tr>
<tr><th>UniProt ID</th><td>[Q15596](https://www.uniprot.org/uniprot/Q15596)</td></tr>
<tr><th>Ensembl ID</th><td>[ENSG00000140396](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000140396)</td></tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>
</div>

Overview

NCOA2 (Nuclear Receptor Coactivator 2), also known as GRIP1 (Glucocorticoid Receptor-Interacting Protein 1) or TIF2 (Transcriptional Intermediary Factor 2), is a transcriptional coactivator that plays a critical role in nuclear receptor-mediated gene transcription. As a member of the p160/SRC (Steroid Receptor Coactivator) family, NCOA2 serves as a bridge between nuclear receptors and the general transcription machinery, amplifying gene expression programs that are essential for neuronal function, synaptic plasticity, and cellular survival [@xu1999][@leo2000].

Function

NCOA2 is a ~175 kDa protein containing multiple functional domains that mediate protein-protein interactions:

Transcriptional Coactivation

• N-terminal Domain: Contains basic helix-loop-helix (bHLH) and PAS (PER-ARNT-SIM) domains that mediate dimerization and DNA binding [@xu1999].
• C-terminal Activating Domains: Three autonomous activation domains (AD1, AD2, AD3) that recruit coactivators including histone acetyltransferases (CBP/p300), histone methyltransferases, and the Mediator complex [@leo2000].
• LXXLL Motifs: Seven LXXLL motifs that facilitate binding to nuclear receptor AF-2 domains in a ligand-dependent manner [@mckenna2002].

Key Nuclear Receptors

NCOA2 coactivates numerous nuclear receptors relevant to neurodegeneration:

• Estrogen Receptors (ERα, ERβ): Critical for neuroprotection, mitochondrial function, and cognitive function [@brinton2008].
• Glucocorticoid Receptor (GR): Regulates stress response and neuronal viability [@sapolsky1996].
• Thyroid Hormone Receptors (TRα, TRβ): Essential for brain development and myelin maintenance [@bernal2000].
• Retinoid X Receptors (RXR): Partners in nuclear receptor heterodimers that regulate gene networks involved in neuronal survival [@mangelsdorf1995].
• Liver X Receptors (LXR): Regulate cholesterol metabolism and inflammation in the brain [@zelcer2006].

Disease Associations

Alzheimer's Disease

NCOA2 has several connections to Alzheimer's disease pathogenesis:

• Estrogen Signaling: By coactivating estrogen receptors, NCOA2 participates in estrogen-mediated neuroprotection against [amyloid-beta](/proteins/amyloid-beta) toxicity. Dysregulation of NCOA2 may contribute to the loss of estrogen's neuroprotective effects in post-menopausal women [@brinton2008].
• APP Processing: Nuclear receptor signaling involving NCOA2 can modulate [amyloid precursor protein](/entities/app-protein) (APP) processing and amyloid-beta production through transcriptional regulation of APP-processing enzymes [@hiltunen2009].
• [Tau](/proteins/tau) Phosphorylation: Thyroid hormone signaling through NCOA2-coactivated receptors can influence tau kinase and phosphatase activity [@bernal2000].
• Mitochondrial Function: NCOA2-mediated activation of ERRα (Estrogen-Related Receptor Alpha) promotes mitochondrial biogenesis and function, which is impaired in AD [@yang2011].

Parkinson's Disease

• Dopaminergic Neuron Survival: NCOA2 coactivates receptors that promote survival of dopaminergic [neurons](/entities/neurons). Thyroid hormone (T3) signaling through TRβ, facilitated by NCOA2, has been shown to protect against MPTP-induced parkinsonism [@das1999].
• [Alpha-Synuclein](/proteins/alpha-synuclein) Expression: Nuclear receptor pathways involving NCOA2 may regulate alpha-synuclein expression, though this remains to be fully characterized.
• Neuroinflammation: LXR signaling, which can be enhanced by NCOA2, has anti-inflammatory effects in microglial cells that may be protective in PD [@zelcer2006].

Amyotrophic Lateral Sclerosis (ALS)

• Glutamate Excitotoxicity: NCOA2's role in glucocorticoid signaling may influence glutamate excitotoxicity, a key mechanism in ALS pathogenesis [@sapolsky1996].
• Energy Metabolism: Dysregulation of nuclear receptor signaling involved in energy metabolism may contribute to motor neuron degeneration [@pasinetti2006].

Huntington's Disease

• Transcriptional Dysregulation: NCOA2 function is perturbed in HD, contributing to the widespread transcriptional alterations observed in the disease. Restoring NCOA2-mediated transcriptional programs has shown promise in preclinical models [@yohrling2003].
• BDNF Expression: NCOA2 coactivates receptors that regulate brain-derived neurotrophic factor (BDNF) expression, which is reduced in HD [@zuccato2009].

Expression

Brain Expression

• Regional Distribution: NCOA2 is widely expressed throughout the brain, with high levels in the [cortex](/brain-regions/cortex), [hippocampus](/brain-regions/hippocampus), basal ganglia, and cerebellum [@ncoa2003].
• Cellular Localization: Expressed in both neurons and glial cells, with particular enrichment in pyramidal neurons and Purkinje cells [@ncoa2003].
• Subcellular Localization: Primarily nuclear, consistent with its role as a transcriptional coactivator.

Regulation

NCOA2 expression and activity are regulated at multiple levels:

• Transcriptional Regulation: Induced by nuclear receptor ligands including estrogen, thyroid hormone, and glucocorticoids [@xu1999].
• Post-translational Modifications: Phosphorylation, acetylation, and SUMOylation regulate NCOA2 activity and stability [@wu2006].
• Cellular Signaling: Multiple kinase pathways (MAPK, PKA, Akt) can phosphorylate and activate NCOA2 [@wu2006].

Key Publications

See Also

• [Nuclear Receptor Coactivators](/institutions/ucl)
• [Transcriptional Regulation in Neurodegeneration](/transcriptional-regulation-in-neurodegeneration)
• [Estrogen Signaling in the Brain](/genes/th)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [Amyotrophic Lateral Sclerosis](/diseases/amyotrophic-lateral-sclerosis)
• [Huntington's Disease](/diseases/huntington-disease)

External Links

• [NCBI Gene: NCOA2](https://www.ncbi.nlm.nih.gov/gene/10499)
• [UniProt: Q15596](https://www.uniprot.org/uniprot/Q15596)
• [Ensembl: ENSG00000140396](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000140396)
• [PubMed: NCOA2 neurodegeneration](https://pubmed.ncbi.nlm.nih.gov/?term=NCOA2+neurodegeneration)

References