SCARB2 Gene

SCARB2 Gene

Introduction

Scarb2 Gene 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-gene">
<table>
<tr><th>Gene Symbol</th><td><strong>SCARB2</strong></td></tr>
<tr><th>Full Name</th><td>Scavenger Receptor Class B Member 2</td></tr>
<tr><th>Chromosomal Location</th><td>4q21.1</td></tr>
<tr><th>NCBI Gene ID</th><td>950</td></tr>
<tr><th>OMIM</th><td>603257</td></tr>
<tr><th>Ensembl ID</th><td>ENSG00000138760</td></tr>
<tr><th>UniProt ID</th><td>Q14108</td></tr>
<tr><th>Protein</th><td>LIMP-2</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a>, <a href="/wiki/obesity" style="color:#ef9a9a">Obesity</a>, <a href="/wiki/rem-sleep-behavior-disorder" style="color:#ef9a9a">REM sleep behavior disorder</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">32 edges</a></td>
</tr>
</table>
</div>

Overview

SCARB2 (Scavenger Receptor Class B Member 2), also known as LIMP-2 (Lysosomal Integral Membrane Protein 2), is a transmembrane receptor protein primarily involved in lysosomal enzyme targeting and membrane trafficking. It is a significant risk gene for Parkinson's disease (PD) and causes a rare neurodevelopmental disorder when mutated.

SCARB2 Gene

Introduction

Scarb2 Gene 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-gene">
<table>
<tr><th>Gene Symbol</th><td><strong>SCARB2</strong></td></tr>
<tr><th>Full Name</th><td>Scavenger Receptor Class B Member 2</td></tr>
<tr><th>Chromosomal Location</th><td>4q21.1</td></tr>
<tr><th>NCBI Gene ID</th><td>950</td></tr>
<tr><th>OMIM</th><td>603257</td></tr>
<tr><th>Ensembl ID</th><td>ENSG00000138760</td></tr>
<tr><th>UniProt ID</th><td>Q14108</td></tr>
<tr><th>Protein</th><td>LIMP-2</td></tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a>, <a href="/wiki/obesity" style="color:#ef9a9a">Obesity</a>, <a href="/wiki/rem-sleep-behavior-disorder" style="color:#ef9a9a">REM sleep behavior disorder</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">32 edges</a></td>
</tr>
</table>
</div>

Overview

SCARB2 (Scavenger Receptor Class B Member 2), also known as LIMP-2 (Lysosomal Integral Membrane Protein 2), is a transmembrane receptor protein primarily involved in lysosomal enzyme targeting and membrane trafficking. It is a significant risk gene for Parkinson's disease (PD) and causes a rare neurodevelopmental disorder when mutated.

Function

SCARB2/LIMP-2 encodes a highly glycosylated type I transmembrane protein that serves multiple functions:

Lysosomal Enzyme Targeting

LIMP-2 acts as a mannose-6-phosphate-independent targeting receptor for β-glucocerebrosidase (GCase, encoded by GBA1)[@matsuda2015]. It binds GCase in the ER and facilitates its transport to lysosomes. This function is critical because:

• GCase deficiency leads to Gaucher disease
• Reduced GCase activity in neurons contributes to [α-synuclein](/proteins/alpha-synuclein) accumulation

Endosomal/Lysosomal Trafficking

• Mediates fusion of endosomes and lysosomes
• Participates in [autophagy](/entities/autophagy) regulation
• Maintains lysosomal membrane integrity

Membrane Reorganization

• Involved in phagosome maturation
• Supports membrane recycling pathways

Disease Associations

Parkinson's Disease

SCARB2 is a risk gene for sporadic PD. GWAS have identified variants that:

• Increase PD risk (OR ~1.3-1.5)[@bohm2013]
• May affect lysosomal GCase activity
• Contribute to α-synuclein clearance deficits

• Both genes affect lysosomal function
• Compound risk increases PD susceptibility
• Explains some cases of GBA-associated PD

Action Myoclonus-Renal Failure Syndrome (AMRF)

Homozygous or compound heterozygous mutations in SCARB2 cause AMRF:

• Progressive myoclonus epilepsy
• Renal failure
• Usually fatal in young adults

Other Neurological Conditions

• Dementia with Lewy Bodies: Risk variant carriers show Lewy body pathology
• Multiple System Atrophy: Possible lysosomal involvement
• Gaucher Disease: LIMP-2 deficiency exacerbates GCase dysfunction

Expression

SCARB2 is widely expressed:

• Brain: Substantia nigra, [hippocampus](/brain-regions/hippocampus), [cortex](/brain-regions/cortex), cerebellum
• Peripheral tissues: Kidney, liver, spleen, lung
• Cell types: [Neurons](/entities/neurons), [microglia](/entities/microglia), [astrocytes](/entities/astrocytes), oligodendrocytes

• Lysosomal membranes
• Endosomal compartments
• Some plasma membrane expression

Allen Brain Atlas Data

Gene Expression

• Cerebral cortex - Moderate expression in pyramidal neurons
• Hippocampus - Moderate expression in CA1-CA3 pyramidal cells
• Basal ganglia - High expression in striatum (caudate/putamen)
• Cerebellum - Low-moderate expression in Purkinje cells
• Substantia nigra - Moderate expression in dopaminergic neurons

Single-Cell Expression

• Highest expression in medium spiny neurons (striatum)
• Moderate expression in cortical pyramidal neurons
• Detectable expression in astrocytes and microglia
• Lower expression in oligodendrocytes

Cell Type Specific Expression

• Neurons: Moderate expression across most neuronal subtypes
• Glia: Higher in astrocytes compared to microglia
• Regional variation: Highest in basal ganglia and thalamus

Brain Region Expression Table

Therapeutic Implications

GBA Modulation

• SCARB2 enhancers could improve GCase trafficking
• Small molecule chaperones targeting the SCARB2-GCase interaction

Gene Therapy

• AAV-mediated SCARB2 expression to restore lysosomal function
• CRISPR approaches to correct pathogenic variants

Biomarkers

• SCARB2 expression levels as a lysosomal function marker
• Interaction with GCase activity measurements

Key Publications

See Also

• [Parkinson's Disease](/diseases/parkinsons-disease)
• [GBA Gene](/proteins/gba1-protein)
• [Alpha-Synuclein](/proteins/snca-protein)
• [Lysosomal Dysfunction Pathway](/mechanisms/lysosomal-dysfunction)
• [Gaucher Disease](/diseases/gaucher-disease)

External Links

• [NCBI Gene: SCARB2](https://www.ncbi.nlm.nih.gov/gene/950)
• [UniProt: LIMP-2](https://www.uniprot.org/uniprot/Q14108)
• [OMIM: SCARB2](https://www.omim.org/entry/603257)

Background

The study of Scarb2 Gene 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

Pathway Diagram

The following diagram shows the key molecular relationships involving SCARB2 Gene discovered through SciDEX knowledge graph analysis: