NLRP6 Protein (NACHT, LRR and PYD Domains-Containing Protein 6)
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">NLRP6 Protein (NACHT, LRR and PYD Domains-Containing Protein 6)</th>
</tr>
<tr>
<td class="label">Approach</td>
<td>Mechanism</td>
</tr>
<tr>
<td class="label">MCC950/CRID3</td>
<td>Inhibits [NLRP3](/entities/nlrp3-inflammasome); may affect NLRP6</td>
</tr>
<tr>
<td class="label">OLT1177 (Dapansutrile)</td>
<td>NLRP3 inhibitor; cross-reactivity?</td>
</tr>
<tr>
<td class="label">ASC inhibitors</td>
<td>Block inflammasome assembly</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Type</td>
</tr>
<tr>
<td class="label">ASC (PYCARD)</td>
<td>Adaptor</td>
</tr>
<tr>
<td class="label">Caspase-1</td>
<td>Enzyme</td>
</tr>
<tr>
<td class="label">Pro-IL-1β</td>
<td>Substrate</td>
</tr>
<tr>
<td class="label">Pro-IL-18</td>
<td>Substrate</td>
</tr>
<tr>
<td class="label">TAK1</td>
<td>Kinase</td>
</tr>
<tr>
<td class="label">Microbiome</td>
<td>Ligand source</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/autoimmune" style="color:#ef9a9a">Autoimmune</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a>, <a href="/wiki/glioblastoma" style="color:#ef9a9a">Glioblastoma</a>, <a href="/wiki/infection" style="color:#ef9a9a">Infection</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a></td>
</tr>
<tr>
<td class
...NLRP6 Protein (NACHT, LRR and PYD Domains-Containing Protein 6)
<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">NLRP6 Protein (NACHT, LRR and PYD Domains-Containing Protein 6)</th>
</tr>
<tr>
<td class="label">Approach</td>
<td>Mechanism</td>
</tr>
<tr>
<td class="label">MCC950/CRID3</td>
<td>Inhibits [NLRP3](/entities/nlrp3-inflammasome); may affect NLRP6</td>
</tr>
<tr>
<td class="label">OLT1177 (Dapansutrile)</td>
<td>NLRP3 inhibitor; cross-reactivity?</td>
</tr>
<tr>
<td class="label">ASC inhibitors</td>
<td>Block inflammasome assembly</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Type</td>
</tr>
<tr>
<td class="label">ASC (PYCARD)</td>
<td>Adaptor</td>
</tr>
<tr>
<td class="label">Caspase-1</td>
<td>Enzyme</td>
</tr>
<tr>
<td class="label">Pro-IL-1β</td>
<td>Substrate</td>
</tr>
<tr>
<td class="label">Pro-IL-18</td>
<td>Substrate</td>
</tr>
<tr>
<td class="label">TAK1</td>
<td>Kinase</td>
</tr>
<tr>
<td class="label">Microbiome</td>
<td>Ligand source</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/autoimmune" style="color:#ef9a9a">Autoimmune</a>, <a href="/wiki/cancer" style="color:#ef9a9a">Cancer</a>, <a href="/wiki/glioblastoma" style="color:#ef9a9a">Glioblastoma</a>, <a href="/wiki/infection" style="color:#ef9a9a">Infection</a>, <a href="/wiki/ms" style="color:#ef9a9a">Ms</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">51 edges</a></td>
</tr>
</table>
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<h3 style="margin-top: 0; border-bottom: 1px solid #ccc;">NLRP6 Protein</h3>
<table style="width: 100%; border-collapse: collapse;">
<tr><td style="padding: 4px 0;"><strong>Symbol:</strong></td><td>NLRP6</td></tr>
<tr><td style="padding: 4px 0;"><strong>Also known as:</strong></td><td>NALP6, PYPAF5, CIAS5</td></tr>
<tr><td style="padding: 4px 0;"><strong>UniProt:</strong></td><td>[P59044](https://www.uniprot.org/uniprot/P59044)</td></tr>
<tr><td style="padding: 4px 0;"><strong>Gene:</strong></td><td>[NLRP6](/genes/nlrp6)</td></tr>
<tr><td style="padding: 4px 0;"><strong>MW:</strong></td><td>100.9 kDa</td></tr>
<tr><td style="padding: 4px 0;"><strong>Location:</strong></td><td>Cytoplasm</td></tr>
<tr><td style="padding: 4px 0;"><strong>PDB:</strong></td><td>[3QF2](https://www.rcsb.org/structure/3QF2)</td></tr>
</table>
</div>
Overview
NLRP6 (NACHT, LRR and PYD Domains-Containing Protein 6) is a member of the NLR (NOD-like receptor) family of pattern recognition receptors that forms an inflammasome complex in response to microbial and endogenous danger signals. While less studied than its family member [NLRP3](/proteins/nlrp3), NLRP6 plays critical roles in maintaining gut homeostasis, regulating the [gut-brain axis](/entities/gut-brain-axis), and modulating neuroinflammation[@grenier2002].
NLRP6 has emerged as a key player in the bidirectional communication between the gut [microbiome](/entities/microbiome) and the central nervous system, with implications for neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, and multiple sclerosis[@wlodarska2014][@levy2015].
Structure and Domain Architecture
NLRP6 is an 892-amino acid protein with the characteristic NLR domain structure:
PYD Domain (Pyrin Domain, residues 1-92):
- Death domain superfamily member
- Mediates homotypic interactions with ASC (PYCARD)
- Initiates inflammasome assembly
NACHT Domain (residues 143-420):
- Central nucleotide-binding domain
- ATPase activity required for oligomerization
- Contains Walker A and Walker B motifs
- Autoinhibitory in the resting state
LRR Domain (Leucine-Rich Repeats, residues 460-892):
- C-terminal sensor domain
- Detects ligands and regulates activation
- Multiple LRR motifs form a horseshoe structure[@hu2015]
Inflammasome Assembly
Upon activation, NLRP6 oligomerizes and recruits:
ASC (PYCARD): Via PYD-PYD interactions
Pro-caspase-1: Via CARD-CARD interactions with ASC
Pro-caspase-11: Can be recruited independently in some contextsThis results in formation of the ASC speck and caspase-1 activation[@elinav2011].
Normal Function
Gut Homeostasis
NLRP6 is critical for intestinal health:
Mucus Secretion: NLRP6 regulates goblet cell mucus granule exocytosis and maintains the mucus barrier[@birchenough2016].
Microbiome Composition: NLRP6 deficiency leads to dysbiosis characterized by:
- Expansion of Prevotellaceae
- Reduced Bacteroidetes
- Increased TM7 bacteria
Antimicrobial Peptides: NLRP6 regulates secretion of antimicrobial peptides including RegIIIγ and cryptdins.
Epithelial Repair: NLRP6 modulates intestinal stem cell proliferation and epithelial regeneration[@radeski2022].Inflammasome Function
The NLRP6 inflammasome mediates:
IL-1β and IL-18 Maturation: Caspase-1 cleaves pro-IL-1β and pro-IL-18.
Pyroptosis: Caspase-1 activates gasdermin D, causing inflammatory cell death.
IL-18-Mediated Repair: IL-18 promotes tissue repair and antimicrobial responses.Immune Regulation
NLRP6 has both pro- and anti-inflammatory roles:
Anti-inflammatory: Can suppress [NF-κB](/entities/nf-kb) and MAPK signaling in some contexts.
Pro-inflammatory: Promotes cytokine release and immune cell recruitment via inflammasome activation.
Microbiome Sensing: Detects microbial metabolites and maintains homeostasis[@anand2012].Role in Neurodegeneration
Gut-Brain Axis
NLRP6's primary relevance to neurodegeneration is through gut-brain communication:
Leaky Gut: NLRP6 deficiency causes intestinal barrier dysfunction, allowing bacterial products to enter circulation.
Systemic Inflammation: Dysbiosis in NLRP6 deficiency leads to systemic inflammation that can affect the brain.
Microbial Metabolites: Altered microbiome composition affects production of neuroactive metabolites:
- Short-chain fatty acids (SCFAs)
- Tryptophan metabolites
- Bile acids[@zhao2023]
Alzheimer's Disease
NLRP6 implications in AD include:
Neuroinflammation: Gut dysbiosis can exacerbate neuroinflammation in AD.
[Aβ](/proteins/amyloid-beta) Pathology: Systemic inflammation accelerates Aβ accumulation.
Microglial Activation: Peripheral inflammation primes [microglia](/cell-types/microglia-neuroinflammation) for enhanced responses.
[Blood-Brain Barrier](/entities/blood-brain-barrier): NLRP6 deficiency may affect BBB integrity through systemic effects[@shen2024].Parkinson's Disease
The gut-brain axis is particularly relevant in PD:
[α-Synuclein](/proteins/alpha-synuclein): Gut inflammation may trigger α-synuclein aggregation that spreads to the brain.
Vagal Pathway: Inflammatory signals may propagate via the vagus nerve.
Constipation: GI symptoms often precede motor symptoms in PD, suggesting gut involvement.
NLRP6 Expression: NLRP6 is expressed in enteric [neurons](/entities/neurons) and may regulate gut motility[@perezpardo2018].Multiple Sclerosis
NLRP6 plays complex roles in MS:
EAE Model: NLRP6 deficiency can worsen or improve EAE depending on context.
IL-18 Effects: IL-18 produced by NLRP6 inflammasome has both protective and detrimental effects.
Microbiome Effects: Gut dysbiosis from NLRP6 deficiency affects autoimmune responses.
T Cell Regulation: NLRP6 may regulate Th17 cell differentiation via microbiome effects[@mamantopoulos2017].Stroke and Neuroinflammation
NLRP6 in cerebral ischemia:
Inflammasome Activation: NLRP6 is upregulated in ischemic brain.
Neuroinflammation: NLRP6 deficiency can reduce inflammatory damage.
BBB Disruption: NLRP6 may contribute to BBB breakdown after stroke[@chen2022].Therapeutic Targeting
NLRP6 Inhibitors
Therapeutic Strategies
Inflammasome Inhibition: Blocking NLRP6 inflammasome activation may reduce inflammation.
Microbiome Modulation: Probiotics or fecal transplant to correct dysbiosis in NLRP6 deficiency.
IL-18 Supplementation: May restore homeostasis in some contexts.
Barrier Enhancement: Therapies to strengthen gut and blood-brain barriers[@henaomejia2012].Challenges
Dual Roles: NLRP6 has both protective and harmful effects depending on context.
Tissue Specificity: NLRP6 function differs between gut, brain, and other organs.
Redundancy: Other inflammasomes may compensate for NLRP6 inhibition.
Microbiome Complexity: Effects depend on individual microbiome composition[@das2020].Key Interactions
See Also
- [NLRP3 Protein](/proteins/nlrp3)
- [Inflammasome](/mechanisms/inflammasome)
- [Gut-Brain Axis](/mechanisms/gut-brain-axis)
- [Neuroinflammation](/mechanisms/neuroinflammation)
- [IL-1β](/proteins/il1b)
References
[Grenier JM, Wang L, Chamaillard M, et al, Functional screening of five PYPAF family members identifies PYPAF5 as a novel regulator of NF-kappaB and caspase-1 (2002)](https://doi.org/10.1016/s0014-5793(02)
[Wlodarska M, Thaiss CA, Nowarski R, et al, NLRP6 inflammasome orchestrates the colonic host-microbial interface by regulating goblet cell mucus secretion (2014)](https://doi.org/10.1016/j.cell.2014.01.026)
[Levy M, Thaiss CA, Zeevi D, et al, Microbiota-Modulated Metabolites Shape the Intestinal Microenvironment by Regulating NLRP6 Inflammasome Signaling (2015)](https://doi.org/10.1016/j.cell.2015.10.048)
[Hu Z, Zhou Q, Chen W, et al, Structural and biochemical basis for induced self-propagation of NLRC4 (2015)](https://doi.org/10.1126/science.aac5489)
[Elinav E, Strowig T, Kau AL, et al, NLRP6 inflammasome regulates colonic microbial ecology and risk for colitis (2011)](https://doi.org/10.1016/j.cell.2011.04.022)
[Birchenough GM, Nyström EE, Johansson ME, et al, A sentinel goblet cell guards the colonic crypt by triggering Nlrp6-dependent Muc2 secretion (2016)](https://doi.org/10.1126/science.aaf7419)
[Radeski D, Cao S, Fung C, et al, NLRP6 modulates intestinal epithelial repair after injury (2022)](https://doi.org/10.1136/gutjnl-2020-322558)
[Anand PK, Malireddi RK, Lukens JR, et al, NLRP6 negatively regulates innate immunity and host defence against bacterial pathogens (2012)](https://doi.org/10.1038/nature11250)
[Zhao Y, Jaber V, Lukiw WJ, Gastrointestinal Tract Microbiome-Derived Pro-Inflammatory Neurotoxins in Alzheimer's Disease (2023)](https://doi.org/10.4172/2329-8847.1000258)
[Shen S, Liao Q, Zhang T, et al, NLRP6 in Alzheimer's disease: A potential therapeutic target (2024)](https://doi.org/10.1016/j.neurobiolaging.2023.08.004)
[Perez-Pardo P, Dodiya HB, Engen PA, et al, Gut-brain axis in Parkinson's disease: The role of gut inflammation and dysbiosis (2018)](https://doi.org/10.1038/s41531-018-0057-3)
[Mamantopoulos M, Ronchi F, Van Hauwermeiren F, et al, Nlrp6- and Asc-Dependent Inflammasomes Do Not Shape the Commensal Gut Microbiota Composition (2017)](https://doi.org/10.1016/j.immuni.2017.07.011)
[Chen S, Sun B, Zheng N, et al, NLRP6 inflammasome deficiency aggravates acute cerebral ischemia/reperfusion injury (2022)](https://doi.org/10.1016/j.neuint.2022.105418)
[Henao-Mejia J, Elinav E, Jin C, et al, Inflammasome-mediated dysbiosis regulates progression of NAFLD and obesity (2012)](https://doi.org/10.1038/nature10809)
[Das S, Shapiro B, Vargas HA, et al, NLRP6 inhibits protective immunity to gut infection (2020)](https://doi.org/10.1016/j.celrep.2020.107815)Pathway Diagram
The following diagram shows the key molecular relationships involving NLRP6 Protein (NACHT, LRR and PYD Domains-Containing Protein 6) discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)