LRP5 Protein

LRP5 Protein

Introduction

Lrp5 Protein 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 class="infobox infobox-protein">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">LRP5 Protein</th></tr>
<tr><td><strong>Protein Name</strong></td><td>Low-density lipoprotein receptor-related protein 5</td></tr>
<tr><td><strong>Gene Symbol</strong></td><td>LRP5</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[4041](https://www.ncbi.nlm.nih.gov/gene/4041)</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[O75177](https://www.uniprot.org/uniprot/O75177)</td></tr>
<tr><td><strong>MW</strong></td><td>179 kDa</td></tr>
<tr><td><strong>Subcellular Location</strong></td><td>Cell membrane, Endosomes</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/atherosclerosis" style="color:#ef9a9a">Atherosclerosis</a>, <a href="/wiki/autosomal-dominant-polycystic-kidney-diseases" style="color:#ef9a9a">Autosomal Dominant Polycystic Kidney Diseases</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">67 edges</a></td>
</tr>
</table>
</div>

Overview

LRP5 Protein

Introduction

Lrp5 Protein 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 class="infobox infobox-protein">
<table>
<tr><th colspan="2" style="background:#e8f4f8; text-align:center; font-size:1.1em;">LRP5 Protein</th></tr>
<tr><td><strong>Protein Name</strong></td><td>Low-density lipoprotein receptor-related protein 5</td></tr>
<tr><td><strong>Gene Symbol</strong></td><td>LRP5</td></tr>
<tr><td><strong>NCBI Gene ID</strong></td><td>[4041](https://www.ncbi.nlm.nih.gov/gene/4041)</td></tr>
<tr><td><strong>UniProt ID</strong></td><td>[O75177](https://www.uniprot.org/uniprot/O75177)</td></tr>
<tr><td><strong>MW</strong></td><td>179 kDa</td></tr>
<tr><td><strong>Subcellular Location</strong></td><td>Cell membrane, Endosomes</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/atherosclerosis" style="color:#ef9a9a">Atherosclerosis</a>, <a href="/wiki/autosomal-dominant-polycystic-kidney-diseases" style="color:#ef9a9a">Autosomal Dominant Polycystic Kidney Diseases</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">67 edges</a></td>
</tr>
</table>
</div>

Overview

LRP5 (Low-density lipoprotein receptor-related protein 5) is a member of the LDL receptor family that functions as a co-receptor for Wnt/beta-catenin signaling["@he2004"]. Originally characterized for its role in bone mass regulation, LRP5 is also expressed in the central nervous system where it plays important roles in neuronal development, synaptic plasticity, and cognitive function["@gong2001"]. LRP5 variants have been associated with Alzheimer's disease, Parkinson's disease, and other neurodegenerative disorders.

Molecular Function

Wnt Co-receptor Function

LRP5 serves as a critical Wnt co-receptor:

• Wnt binding: Binds Wnt ligands (Wnt1, Wnt3, Wnt3a, Wnt5a)
• Frizzled interaction: Forms receptor complexes with Frizzled proteins
• β-catenin stabilization: Initiates canonical Wnt/β-catenin signaling
• Signal modulation: Regulates downstream gene transcription

Lipoprotein Receptor Function

As an LDL receptor family member:

• Lipoprotein binding: Binds various lipoproteins
• Endocytosis: Mediates uptake of ligands
• LRP6: Closely related paralog with overlapping functions

Neuronal Functions

In [neurons](/entities/neurons) and synapses:

• Synaptic plasticity: Regulates hippocampal [long-term potentiation](/mechanisms/long-term-potentiation) (LTP)
• Cognitive function: Important for learning and memory
• Neurogenesis: Affects neural progenitor cell function
• Dendritic spine morphology: Regulates spine density and shape

Disease Associations

Alzheimer's Disease

LRP5 is genetically and functionally linked to AD[@de2007]:

| Variant | Effect | Association |
|---------|--------|-------------|
| p.A1330V | Gain of function | Reduced AD risk |
| p.S371L | Altered function | Increased risk |
| Expression | Reduced in AD brain | Pathogenic |

Mechanisms:

• Wnt/β-catenin signaling impairment
• Synaptic dysfunction
• [Aβ](/proteins/amyloid-beta) interactions

Parkinson's Disease

• GWAS associations: LRP5 variants linked to PD risk
• Dopaminergic function: Affects dopamine neuron survival
• LRP6 connection: Shared pathways with LRP5

Bone Disorders

• High bone mass: Gain-of-function mutations
• Osteoporosis-pseudoglioma: Loss-of-function mutations

Pathway Interactions

Wnt/β-Catenin Signaling

• LRP6: Functional paralog and co-receptor[@macdonald2009]
• DVL: Dishevelled downstream of LRP5
• GSK3β: Inhibited by Wnt signaling
• β-catenin: Stabilized and translocates to nucleus

Synaptic Signaling

• PSD-95: Postsynaptic density protein
• NMDA receptors: Interaction with synaptic proteins
• AMPA receptors: Regulates trafficking

Lipid Metabolism

• [Apolipoprotein E](/proteins/apoe): LRP5 interacts with ApoE
• Cholesterol: May affect neuronal cholesterol homeostasis
• [Amyloid precursor protein](/entities/app-protein): APP processing interactions

Therapeutic Implications

Wnt Pathway Modulators

• LRP5 agonists: Wnt pathway activators
• Small molecule Wnt activators: e.g., CHIR99021
• LRP5/LRP6 bifunctional agents: In development

Targeting LRP5 for Neurodegeneration

• [Blood-brain barrier](/entities/blood-brain-barrier): Challenge for CNS delivery
• Peripheral modulation: May affect central Wnt signaling
• Combination approaches: With other pathway modulators

Background

The study of Lrp5 Protein 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

• LRP5 Gene
• [LRP6 Protein](/proteins/lrp6-protein)
• [Wnt Signaling Pathway](/mechanisms/wnt-signaling-neurodegeneration)
• [Alzheimer's Disease Mechanisms](/mechanisms/alzheimers-disease-mechanisms)
• [Parkinson's Disease Mechanisms](/mechanisms/parkinsons-disease-mechanisms)
• [Synaptic Plasticity Pathway](/mechanisms/synaptic-dysfunction)

Pathway Diagram

The following diagram shows the key molecular relationships involving LRP5 Protein discovered through SciDEX knowledge graph analysis: