LRP6 Protein

LRP6 Protein

Introduction

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">LRP6 Protein</th>
</tr>
<tr>
<td class="label">Domain</td>
<td>Position</td>
</tr>
<tr>
<td class="label">Signal peptide</td>
<td>1-23 aa</td>
</tr>
<tr>
<td class="label">LDLR repeats 1-3</td>
<td>24-600 aa</td>
</tr>
<tr>
<td class="label">LDLR repeats 4-6</td>
<td>600-900 aa</td>
</tr>
<tr>
<td class="label">EGF-like domains</td>
<td>900-1200 aa</td>
</tr>
<tr>
<td class="label">Transmembrane</td>
<td>1380-1402 aa</td>
</tr>
<tr>
<td class="label">Cytoplasmic tail</td>
<td>1403-1613 aa</td>
</tr>
<tr>
<td class="label">Modification</td>
<td>Site</td>
</tr>
<tr>
<td class="label">Phosphorylation</td>
<td>S1490, T1479</td>
</tr>
<tr>
<td class="label">Glycosylation</td>
<td>Multiple</td>
</tr>
<tr>
<td class="label">Palmitoylation</td>
<td>C1351</td>
</tr>
<tr>
<td class="label">Ubiquitination</td>
<td>Multiple</td>
</tr>
<tr>
<td class="label">Partner</td>
<td>Interaction Domain</td>
</tr>
<tr>
<td class="label">Wnt proteins</td>
<td>LDLR repeats</td>
</tr>
<tr>
<td class="label">FZD receptors</td>
<td>Extracellular</td>
</tr>
<tr>
<td class="label">DVL</td>
<td>Cytoplasmic</td>
</tr>
<tr>
<td class="label">AXIN</td>
<td>Cytoplasmic</td>
</tr>
<tr>
<td class="label">GSK3β</td>
<td>Cytoplasmic</td>
</tr>
<tr>
<td class="label">Region

LRP6 Protein

Introduction

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">LRP6 Protein</th>
</tr>
<tr>
<td class="label">Domain</td>
<td>Position</td>
</tr>
<tr>
<td class="label">Signal peptide</td>
<td>1-23 aa</td>
</tr>
<tr>
<td class="label">LDLR repeats 1-3</td>
<td>24-600 aa</td>
</tr>
<tr>
<td class="label">LDLR repeats 4-6</td>
<td>600-900 aa</td>
</tr>
<tr>
<td class="label">EGF-like domains</td>
<td>900-1200 aa</td>
</tr>
<tr>
<td class="label">Transmembrane</td>
<td>1380-1402 aa</td>
</tr>
<tr>
<td class="label">Cytoplasmic tail</td>
<td>1403-1613 aa</td>
</tr>
<tr>
<td class="label">Modification</td>
<td>Site</td>
</tr>
<tr>
<td class="label">Phosphorylation</td>
<td>S1490, T1479</td>
</tr>
<tr>
<td class="label">Glycosylation</td>
<td>Multiple</td>
</tr>
<tr>
<td class="label">Palmitoylation</td>
<td>C1351</td>
</tr>
<tr>
<td class="label">Ubiquitination</td>
<td>Multiple</td>
</tr>
<tr>
<td class="label">Partner</td>
<td>Interaction Domain</td>
</tr>
<tr>
<td class="label">Wnt proteins</td>
<td>LDLR repeats</td>
</tr>
<tr>
<td class="label">FZD receptors</td>
<td>Extracellular</td>
</tr>
<tr>
<td class="label">DVL</td>
<td>Cytoplasmic</td>
</tr>
<tr>
<td class="label">AXIN</td>
<td>Cytoplasmic</td>
</tr>
<tr>
<td class="label">GSK3β</td>
<td>Cytoplasmic</td>
</tr>
<tr>
<td class="label">Region</td>
<td>Expression Level</td>
</tr>
<tr>
<td class="label">[Hippocampus](/brain-regions/hippocampus)</td>
<td>Very high</td>
</tr>
<tr>
<td class="label">[Cortex](/brain-regions/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">Spinal cord</td>
<td>High</td>
</tr>
<tr>
<td class="label">Agent</td>
<td>Target</td>
</tr>
<tr>
<td class="label">Lithium</td>
<td>GSK3β</td>
</tr>
<tr>
<td class="label">CHIR99021</td>
<td>GSK3β</td>
</tr>
<tr>
<td class="label">Wnt agonists</td>
<td>LRP6/FZD</td>
</tr>
<tr>
<td class="label">DKK1 antibodies</td>
<td>Antagonist block</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/alzheimer" style="color:#ef9a9a">Alzheimer</a>, <a href="/wiki/atherosclerosis" style="color:#ef9a9a">Atherosclerosis</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">89 edges</a></td>
</tr>
</table>

Lrp6 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.
title: LRP6 Protein
.infobox.infix-protein
; Protein Name
: LDL Receptor Related Protein 6
; Gene Symbol
: [LRP6](/proteins/lrp6-protein)
; UniProt ID
: [O75151](https://www.uniprot.org/uniprotkb/O75151)
; PDB ID
: 3S94
; Molecular Weight
: 180 kDa (1613 aa)
; Subcellular Localization
: Cell membrane
; Protein Family
: LDLR family

Overview

The LRP6 protein (Low-Density Lipoprotein Receptor-Related Protein 6) is a transmembrane co-receptor essential for canonical Wnt/β-catenin signaling. As a key component of the Wnt receptor complex, LRP6 binds Wnt ligands through its extracellular domain and transduces signals through the intracellular domain to activate β-catenin signaling [@he2004]. LRP6 plays critical roles in embryonic development, tissue patterning, and adult tissue homeostasis. In the nervous system, LRP6 regulates neural progenitor cell proliferation, neuronal differentiation, synapse formation, and synaptic plasticity. LRP6 variants have been associated with increased risk for Alzheimer's disease (AD), making it a molecule of significant therapeutic interest [@de2003][@r2007].

Protein Structure

Domain Architecture

LRP6 is a large transmembrane protein with distinct domains:

Key Structural Features

• LDLR repeat clusters: Three clusters of LDL receptor repeats
• β-propeller motifs: Protein-protein interactions
• NPXY motifs: Endocytosis signals
• PDZ binding: Scaffold protein interactions

Post-Translational Modifications

Molecular Mechanisms

Wnt Receptor Complex Formation

LRP6 functions as a co-receptor with Frizzled (FZD) receptors:

Signal Transduction

Canonical Pathway

Key Interactions

Normal Function in the Nervous System

Neural Development

LRP6 is essential for nervous system development:

Synaptogenesis

LRP6 regulates synapse formation:

• Presynaptic differentiation: Synaptic vesicle organization
• Postsynaptic maturation: Receptor clustering
• Spine formation: Dendritic spine development
• Synaptic plasticity: [LTP](/mechanisms/long-term-potentiation) and LTD modulation

Cognitive Function

• Learning and memory: Required for hippocampus-dependent memory
• Synaptic strength: Maintains synaptic efficacy
• Circuit stability: Long-term neural circuit maintenance

Disease Associations

Alzheimer's Disease

LRP6 in AD pathogenesis [@de2003][@r2007]:

Genetic Evidence:

• LRP6 variants associated with AD risk
• rs2304135, rs6489896 polymorphisms
• Altered Wnt signaling in carriers

• Reduced LRP6 → Impaired Wnt signaling
• Effects on [amyloid precursor protein](/entities/app-protein) (APP) processing
• [Tau](/proteins/tau) phosphorylation dysregulation
• Synaptic dysfunction

• LRP6 agonists restore signaling
• Small molecule activators
• Gene therapy approaches

Parkinson's Disease

LRP6 in PD:

• Protects dopaminergic neurons
• Maintains mitochondrial function
• May influence [α-synuclein](/proteins/alpha-synuclein) pathology

Neurodevelopmental Disorders

• Autism: LRP6 variants in ASD families
• Schizophrenia: Altered LRP6 expression
• Intellectual disability: Rare mutations

Bone Disorders

LRP6 is also important for:

• Bone density
• Osteoporosis risk
• Tooth development

Expression Pattern

Brain Regional Distribution

Cell-Type Expression

• [Neurons](/entities/neurons): High expression, synaptic localization
• Neural progenitors: High, developmental
• [Astrocytes](/entities/astrocytes): Moderate
• [Microglia](/entities/microglia): Low, inducible

Therapeutic Targeting

Small Molecule Modulators

Biological Approaches

• Recombinant Wnt proteins: Activate LRP6
• AAV-mediated expression: Gene therapy
• LRP6 modulators: Direct targeting

Therapeutic Strategies

Key Publications

See Also

• [Wnt Signaling Pathway](/mechanisms/wnt-signaling)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [LRP6 Gene](/proteins/lrp6-protein)
• [Frizzled Receptors](/entities/frizzled-receptors)
• [GSK3β](/entities/gsk3-beta)
• [Amyloid-Beta](/proteins/amyloid-beta)
• [Tau Protein](/proteins/tau)
• [Synaptic Plasticity](/mechanisms/synaptic-plasticity)

Background

The study of Lrp6 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.

External Links

• [UniProt: LRP6](https://www.uniprot.org/uniprotkb/O75151)
• [PDB: LRP6](https://www.rcsb.org/structure/3S94)
• [NCBI Protein: LRP6](https://www.ncbi.nlm.nih.gov/protein/?term=LRP6)
• [Gene Ontology: LRP6](https://amigo.geneontology.org/amigo/search/annotation?q=LRP6)

References