PTGS2/COX-2 Protein - Cyclooxygenase-2

PTGS2/COX-2 Protein - Cyclooxygenase-2

Introduction

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">PTGS2/COX-2 Protein - Cyclooxygenase-2</th>
</tr>
<tr>
<td class="label">Drug</td>
<td>Selectivity</td>
</tr>
<tr>
<td class="label">Celecoxib</td>
<td>COX-2 selective</td>
</tr>
<tr>
<td class="label">Rofecoxib</td>
<td>COX-2 selective</td>
</tr>
<tr>
<td class="label">Ibuprofen</td>
<td>Non-selective</td>
</tr>
<tr>
<td class="label">Minocycline</td>
<td>Non-COX</td>
</tr>
</table>

Ptgs2 Cox 2 Protein Cyclooxygenase 2 is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

PTGS2/COX-2 Protein - Cyclooxygenase-2

Introduction

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">PTGS2/COX-2 Protein - Cyclooxygenase-2</th>
</tr>
<tr>
<td class="label">Drug</td>
<td>Selectivity</td>
</tr>
<tr>
<td class="label">Celecoxib</td>
<td>COX-2 selective</td>
</tr>
<tr>
<td class="label">Rofecoxib</td>
<td>COX-2 selective</td>
</tr>
<tr>
<td class="label">Ibuprofen</td>
<td>Non-selective</td>
</tr>
<tr>
<td class="label">Minocycline</td>
<td>Non-COX</td>
</tr>
</table>

Ptgs2 Cox 2 Protein Cyclooxygenase 2 is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

<div style="background:#f8f9fa;border:1px solid #ddd;padding:15px;border-radius:5px;margin:10px 0;"> [@neuroinflammation]
<h3 style="margin-top:0;">PTGS2/COX-2 Protein - Cyclooxygenase-2</h3> [@coxa]
<table style="width:100%;font-size:14px;"> [@coxb]
<tr><td style="padding:5px;font-weight:bold;">Symbol</td><td style="padding:5px;">PTGS2</td></tr> [@pge]
<tr><td style="padding:5px;font-weight:bold;">Protein Name</td><td style="padding:5px;">Prostaglandin-Endoperoxide Synthase 2</td></tr> [@coxc]
<tr><td style="padding:5px;font-weight:bold;">Common Name</td><td style="padding:5px;">Cyclooxygenase-2 (COX-2)</td></tr> [@cyclooxygenases]
<tr><td style="padding:5px;font-weight:bold;">Molecular Weight</td><td>70 kDa</td></tr> [@coxd]
<tr><td style="padding:5px;font-weight:bold;">Enzyme Class</td><td>EC 1.14.99.1 - Peroxidase</td></tr>
<tr><td style="padding:5px;font-weight:bold;">Associated Diseases</td><td>AD, PD, ALS, HD, Stroke, Rheumatoid Arthritis, Cancer</td></tr>
</table>
</div>

Overview

PTGS2 (Prostaglandin-Endoperoxide Synthase 2), commonly known as Cyclooxygenase-2 (COX-2), is a key enzyme in prostaglandin biosynthesis that catalyzes the conversion of arachidonic acid to prostaglandin H2 (PGH2). Unlike the constitutively expressed COX-1, COX-2 is an inducible enzyme upregulated in response to inflammatory stimuli, growth factors, and pathological conditions. In the central nervous system, COX-2 plays complex roles in neuroinflammation, synaptic plasticity, and neuronal survival, making it a critical player in neurodegenerative diseases.

Molecular Structure

COX-2 is a 70 kDa integral membrane protein with a distinctive structure:

• N-terminal membrane-binding domain with four alpha-helices
• C-terminal catalytic domain with peroxidase and cyclooxygenase active sites
• Arachidonic acid binding channel (selective for COX-2)
• Active site contains heme group for peroxidase activity

Isoforms

• Full-length COX-2 (72 kDa): Inducible form
• Alternative splicing variants identified in some tissues

Molecular Function

Cyclooxygenase Activity

• Catalyzes conversion of arachidonic acid to PGG2 (cyclooxygenase reaction)
• Peroxidase activity converts PGG2 to PGH2
• PGH2 is substrate for various prostaglandin synthases

Prostaglandin Production

• Produces PGH2, the precursor for:
• PGE2 (prostaglandin E2) - main pro-inflammatory prostaglandin
• PGD2 - involved in sleep and allergic responses
• PGF2α - smooth muscle contraction
• PGI2 (prostacyclin) - vasodilation, anti-platelet

Regulation

• Transcriptionally induced by: LPS, cytokines (IL-1β, TNF-α), growth factors
• Suppressed by: glucocorticoids, NSAIDs, COX-2 inhibitors
• Post-transcriptional regulation via mRNA stability elements

Expression Pattern

CNS Expression

• Neuronal expression in [cortex](/brain-regions/cortex), [hippocampus](/brain-regions/hippocampus)
• Astrocytic and microglial expression in disease states
• Constitutive expression in some brain regions
• Highly inducible in response to injury/inflammation

Peripheral Expression

• Low basal expression in most tissues
• High expression in inflamed tissues
• Induced in endothelial cells, macrophages

Role in Disease

Alzheimer's Disease

Parkinson's Disease

Amyotrophic Lateral Sclerosis

Huntington's Disease

Stroke and Ischemia

Therapeutic Targeting

NSAIDs and COX-2 Inhibitors

Challenges

• Cardiovascular side effects of selective COX-2 inhibitors
• Timing of intervention critical
• Complex roles (both protective and harmful)

Animal Models

• COX-2 transgenic mice: Enhanced neuroinflammation
• COX-2 knockout mice: Reduced inflammation but altered responses
• Neuron-specific COX-2 overexpression: Synaptic deficits

Background

The study of Ptgs2 Cox 2 Protein Cyclooxygenase 2 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.

See Also

• [Neuroinflammation Pathway](/mechanisms/neuroinflammation-pathway)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [Prostaglandin E2](/genes/gla)
• [Arachidonic Acid Cascade](/institutions/cas)

External Links

• [UniProt: PTGS2](https://www.uniprot.org/uniprot/P35354)
• [NCBI Gene: PTGS2](https://www.ncbi.nlm.nih.gov/gene/5743)
• [GeneCards: PTGS2](https://www.genecards.org/cgi-bin/carddisp.pl?gene=PTGS2)
• [KEGG: Arachidonic Acid Metabolism](https://www.genome.jp/kegg-bin/show_pathway?map=ko00590)

References