PARD6B

gene
On this page

Also known as PAR-6B

Summary

PARD6B (par-6 family cell polarity regulator beta, HGNC:16245) is a protein-coding gene on chromosome 20q13.13, encoding Partitioning defective 6 homolog beta (Q9BYG5). Adapter protein involved in asymmetrical cell division and cell polarization processes. It is a selective cancer dependency (DepMap: 12.9% of cell lines).

This gene is a member of the PAR6 family and encodes a protein with a PSD95/Discs-large/ZO1 (PDZ) domain, an OPR domain and a semi-Cdc42/Rac interactive binding (CRIB) domain. This cytoplasmic protein is involved in asymmetrical cell division and cell polarization processes as a member of a multi-protein complex.

Source: NCBI Gene 84612 — RefSeq curated summary.

At a glance

  • GWAS associations: 1
  • Clinical variants (ClinVar): 50 total
  • Cancer dependency (DepMap): dependent in 12.9% of screened cell lines
  • MANE Select transcript: NM_032521

Identifiers

Gene identifiers

FieldValue
HGNC IDHGNC:16245
Approved symbolPARD6B
Namepar-6 family cell polarity regulator beta
Location20q13.13
Locus typegene with protein product
StatusApproved
AliasesPAR-6B
Ensembl geneENSG00000124171
Ensembl biotypeprotein_coding
OMIM608975
Entrez84612

Gene structure

Transcript identifiers

Ensembl transcripts: 3 — 3 protein_coding

ENST00000371610, ENST00000396039, ENST00000948561

RefSeq mRNA: 1 — MANE Select: NM_032521 NM_032521

CCDS: CCDS33485

Canonical transcript exons

ENST00000371610 — 3 exons

ExonStartEnd
ENSE000008456245073785750738079
ENSE000014556485074965950753741
ENSE000014556525073158050731852

Expression profiles

Bgee: expression breadth ubiquitous, 223 present calls, max score 98.38.

FANTOM5 (CAGE): breadth ubiquitous, TPM avg 35.4848 / max 901.1026, expressed in 1085 samples.

FANTOM5 promoters (13 alternative TSS)

Promoter IDTPM avgSamples expressed
18527515.9549701
18527311.2858876
1852742.8986408
1852661.5428452
1852700.7196198
1852720.6200248
1852670.5318151
1852710.5290202
1852680.4407143
1852690.3020121

Top tissues by expression

269 total, by Bgee expression score (0-100, higher = more expressed):

TissueAnatomy IDExpression scoreQuality
germinal epithelium of ovaryUBERON:000130498.38gold quality
renal medullaUBERON:000036295.21gold quality
pigmented layer of retinaUBERON:000178295.16gold quality
palpebral conjunctivaUBERON:000181293.18gold quality
epithelium of nasopharynxUBERON:000195191.54gold quality
amniotic fluidUBERON:000017391.15gold quality
jejunal mucosaUBERON:000039990.27gold quality
lower lobe of lungUBERON:000894990.10gold quality
mucosa of paranasal sinusUBERON:000503089.94gold quality
esophagus squamous epitheliumUBERON:000692089.80gold quality
bronchial epithelial cellCL:000232887.30gold quality
corpus epididymisUBERON:000435986.90gold quality
spermCL:000001986.71gold quality
parietal pleuraUBERON:000240085.65gold quality
caput epididymisUBERON:000435884.70gold quality
male germ cellCL:000001583.59gold quality
male germ line stem cell (sensu Vertebrata) in testisCL:0000089 ∩ UBERON:000047383.56gold quality
epithelium of esophagusUBERON:000197683.26gold quality
oral cavityUBERON:000016782.88gold quality
pleuraUBERON:000097782.65gold quality
secondary oocyteCL:000065582.46gold quality
mucosa of sigmoid colonUBERON:000499382.42gold quality
colonic mucosaUBERON:000031782.34gold quality
oocyteCL:000002382.11gold quality
visceral pleuraUBERON:000240181.57gold quality
metanephros cortexUBERON:001053381.44gold quality
kidneyUBERON:000211381.39gold quality
cortex of kidneyUBERON:000122580.86gold quality
squamous epitheliumUBERON:000691480.26gold quality
primordial germ cell in gonadCL:0000670 ∩ UBERON:000099180.14gold quality

Single-cell (SCXA)

Detected in 2 experiment(s), a significant marker in 2.

ExperimentMarker?Max mean expression
E-MTAB-6678yes8.23
E-ANND-3no0.00

Regulation

Is transcription factor: no

miRNA regulators (miRDB)

184 targeting PARD6B, top 30 by miRDB confidence (max_score; target_count = how many genes the miRNA targets in total — lower means more specific):

miRNAMax scoreAvg scoremiRNA target_count
HSA-MIR-3613-3P100.0076.367965
HSA-MIR-3163100.0077.238605
HSA-LET-7A-3P100.0074.033932
HSA-LET-7B-3P100.0074.083913
HSA-LET-7F-1-3P100.0074.023928
HSA-MIR-98-3P100.0074.083907
HSA-MIR-5692A100.0074.406850
HSA-MIR-656-3P100.0072.152788
HSA-MIR-3646100.0073.565283
HSA-MIR-5692B100.0071.322622
HSA-MIR-5692C100.0071.322622
HSA-MIR-196A-5P100.0068.16684
HSA-MIR-196B-5P100.0068.16681
HSA-MIR-200B-3P100.0073.312693
HSA-MIR-200C-3P100.0073.352685
HSA-MIR-429100.0073.442698
HSA-MIR-513A-5P100.0069.772465
HSA-MIR-6758-5P100.0066.211470
HSA-MIR-6856-5P100.0065.471298
HSA-MIR-450A-1-3P100.0069.331837
HSA-MIR-4476100.0068.182030
HSA-MIR-6876-5P100.0067.682126
HSA-MIR-4262100.0073.263931
HSA-MIR-428299.9975.366408
HSA-MIR-548C-3P99.9974.017587
HSA-MIR-371B-5P99.9975.344759
HSA-MIR-450099.9972.722367
HSA-MIR-223-3P99.9970.141140
HSA-MIR-27A-3P99.9872.132955
HSA-MIR-27B-3P99.9872.132955

Functional genomics

DepMap (CRISPR cell-line fitness): dependent in 12.9% of screened cell lines.

Literature-anchored findings (GeneRIF, showing 7)

  • The ability of SRC family coactivators to regulate the expression of one of these genes, PARD6B/Par6, was confirmed by using cells individually depleted of SRC-1. (PMID:15677324)
  • Interaction between PAR-3 and the aPKC-PAR-6 complex is indispensable for apical domain development of epithelial cells. (PMID:19401335)
  • This study demonstrates that controlled regulation of PAK4 is required for apical junction formation in lung epithelial cells and highlights potential cross-talk between two Cdc42 targets, PAK4 and Par6B. (PMID:20631255)
  • Data conclude that Par6B and aPKC control mitotic spindle orientation in polarized epithelia and, furthermore, that aPKC coordinately regulates multiple processes to promote morphogenesis. (PMID:21300793)
  • PAK4 phosphorylates Par6B at Ser143 blocking its interaction with Cdc42. (PMID:25662318)
  • found that the polarity determinants Cdc42, Par6B, PKCzeta/iota and the structural proteins ezrin and phospho-ezrin were lost from the apical membrane and accumulated either in the cytoplasm or on the basal side of enterocytes in patients (PMID:26526116)
  • reduced expression of PKCzeta/Pard3/Pard6 contributes to non-small-cell lung cancer epithelial-mesenchymal transition, invasion, and chemoresistance. (PMID:28652146)

Cross-species orthologs

5 orthologs

OrganismSymbolGene ID
danio_reriopard6bENSDARG00000003865
mus_musculusPard6bENSMUSG00000044641
rattus_norvegicusPard6bENSRNOG00000010883
drosophila_melanogasterpar-6FBGN0026192
caenorhabditis_eleganspar-6WBGENE00003921

Paralogs (2): PARD6A (ENSG00000102981), PARD6G (ENSG00000178184)

Protein

Protein identifiers

Partitioning defective 6 homolog betaQ9BYG5 (reviewed: Q9BYG5)

All UniProt accessions (1): Q9BYG5

UniProt curated annotations — full annotation on UniProt →

Function. Adapter protein involved in asymmetrical cell division and cell polarization processes. Probably involved in formation of epithelial tight junctions. Association with PARD3 may prevent the interaction of PARD3 with F11R/JAM1, thereby preventing tight junction assembly. The PARD6-PARD3 complex links GTP-bound Rho small GTPases to atypical protein kinase C proteins.

Subunit / interactions. Interacts with PARD3. Interacts with GTP-bound forms of CDC42 and RAC1. Interacts with GTP-bound RHOQ/TC10. Interacts with PALS1. Interacts with the N-terminal part of PRKCI and PRKCZ. Part of a complex with PARD3, CDC42 or RAC1 and PRKCI or PRKCZ. Part of a complex with LLGL1 and PRKCI. Interacts with PARD3B. Interacts with ECT2.

Subcellular location. Cytoplasm. Cell membrane. Cell junction. Tight junction.

Tissue specificity. Expressed in pancreas and in both adult and fetal kidney. Weakly expressed in placenta and lung. Not expressed in other tissues.

Domain organisation. The pseudo-CRIB domain together with the PDZ domain is required for the interaction with Rho small GTPases. The PDZ domain mediates interaction with PALS1.

Similarity. Belongs to the PAR6 family.

Isoforms (2)

UniProt IDNamesCanonical?
Q9BYG5-11yes
Q9BYG5-22

RefSeq proteins (1): NP_115910* (*=MANE)

Domains & families (InterPro)

IDNameType
IPR000270PB1_domDomain
IPR001478PDZDomain
IPR034868PB1_Par6Domain
IPR036034PDZ_sfHomologous_superfamily
IPR051741PAR6_homologFamily
IPR053793PB1-likeDomain

Pfam: PF00564, PF00595

UniProt features (10 total): domain 3, region of interest 2, splice variant 2, chain 1, compositionally biased region 1, modified residue 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

ModelpLDDTFraction very-high
AF-Q9BYG5-F170.970.40

Functional residue map

Curated UniProt residues grouped by drug-discovery relevance — catalytic, ligand-binding, modification, and mutation-validated positions. Source: UniProtKB sequence features.

Post-translational modifications (1): 11

Function

Pathways and Gene Ontology

Reactome pathways

2 pathways

IDPathway
R-HSA-420029Tight junction interactions
R-HSA-9013424RHOV GTPase cycle

MSigDB gene sets: 198 (showing top): GOBP_ESTABLISHMENT_OR_MAINTENANCE_OF_CELL_POLARITY, TGCACTT_MIR519C_MIR519B_MIR519A, GRAESSMANN_APOPTOSIS_BY_DOXORUBICIN_DN, GRAESSMANN_RESPONSE_TO_MC_AND_DOXORUBICIN_DN, TATTATA_MIR374, GOBP_NEUROGENESIS, KEGG_TIGHT_JUNCTION, GOBP_CELL_JUNCTION_ORGANIZATION, MODULE_205, GOBP_REGULATION_OF_CELLULAR_LOCALIZATION, PYEON_CANCER_HEAD_AND_NECK_VS_CERVICAL_UP, GOCC_APICAL_PLASMA_MEMBRANE, GOBP_CELL_JUNCTION_ASSEMBLY, SENESE_HDAC1_TARGETS_UP, KEGG_ENDOCYTOSIS

GO Biological Process (9): cell-cell junction assembly (GO:0007043), centrosome cycle (GO:0007098), establishment or maintenance of cell polarity (GO:0007163), axonogenesis (GO:0007409), regulation of cell migration (GO:0030334), establishment or maintenance of epithelial cell apical/basal polarity (GO:0045197), cell division (GO:0051301), regulation of cellular localization (GO:0060341), protein-containing complex assembly (GO:0065003)

GO Molecular Function (1): protein binding (GO:0005515)

GO Cellular Component (15): nucleus (GO:0005634), cytosol (GO:0005829), plasma membrane (GO:0005886), bicellular tight junction (GO:0005923), cell cortex (GO:0005938), apical plasma membrane (GO:0016324), cell junction (GO:0030054), extracellular exosome (GO:0070062), tight junction (GO:0070160), PAR polarity complex (GO:0120157), cytoplasm (GO:0005737), membrane (GO:0016020), protein-containing complex (GO:0032991), apical part of cell (GO:0045177), anchoring junction (GO:0070161)

Reactome top-level categories

Rollup of top-2 pathways:

CategoryPathways
Cell-cell junction organization1
RHO GTPase cycle1

GO top-level categories

Rollup of top GO terms by namespace:

CategoryTerms
cellular anatomical structure5
cellular process2
cytoplasm2
cell periphery2
cell junction assembly1
cell-cell junction organization1
cell cycle process1
microtubule organizing center organization1
cell morphogenesis involved in neuron differentiation1
neuron projection morphogenesis1
axon development1
cell migration1
regulation of cell motility1
establishment or maintenance of apical/basal cell polarity1
regulation of localization1
regulation of cellular process1
cellular localization1
cellular component assembly1
protein-containing complex organization1
binding1
intracellular membrane-bounded organelle1
membrane1
apical junction complex1
tight junction1
apical part of cell1
plasma membrane region1
extracellular vesicle1
cell-cell junction1
serine/threonine protein kinase complex1
intracellular anatomical structure1
cellular_component1
cell junction1

Protein interactions and networks

STRING

1032 interactions, top by confidence (×1000):

Protein AProtein BPartner UniProtScore
PARD6BCDC42P21181991
PARD6BPRKCZQ05513917
PARD6BPARD3Q8TEW0896
PARD6BTJP1Q07157671
PARD6BLLGL2Q6P1M3590
PARD6BPRKCIP41743583
PARD6BSMURF1Q9HCE7583
PARD6BJAM2P57087564
PARD6BTIAM1Q13009540
PARD6BRAC1P15154527
PARD6BPARD3BQ8TEW8516
PARD6BPATJQ8NI35510
PARD6BANXA2P07355503
PARD6BCRB3Q9BUF7494
PARD6BRHOAP06749482

IntAct

176 interactions, top by confidence:

ABTypeScore
PARD6BPRKCIpsi-mi:“MI:0915”(physical association)0.960
PRKCIPARD6Bpsi-mi:“MI:0915”(physical association)0.960
PARD6BPRKCIpsi-mi:“MI:0914”(association)0.960
PRKCZPARD6Bpsi-mi:“MI:0915”(physical association)0.950
PARD6APRKCIpsi-mi:“MI:0914”(association)0.950
PARD6BCDC42psi-mi:“MI:0915”(physical association)0.900
CDC42PARD6Bpsi-mi:“MI:0915”(physical association)0.900
PRKCZPRKCIpsi-mi:“MI:0914”(association)0.890
LLGL2PRKCIpsi-mi:“MI:0915”(physical association)0.890

BioGRID (245): PARD6B (Two-hybrid), PARD6B (Two-hybrid), PARD6B (Two-hybrid), PARD6B (Two-hybrid), PARD6B (Two-hybrid), PARD6B (Two-hybrid), PARD6B (Affinity Capture-MS), PARD6B (Affinity Capture-MS), PARD3 (Affinity Capture-MS), LLGL2 (Affinity Capture-MS), PTPN14 (Affinity Capture-MS), LLGL1 (Affinity Capture-MS), ZZEF1 (Affinity Capture-MS), WWC1 (Affinity Capture-MS), PRKCZ (Affinity Capture-MS)

ESM2 similar proteins: A1A5R8, A1L1R5, A2A3K4, A2VDZ4, A5PKL1, A7E379, A8KBE0, B2GUY1, B2RC85, E1B9D8, E9PYQ0, O00444, O00522, O01326, O54852, P0C881, P59111, Q04688, Q08CH7, Q14693, Q1JPG1, Q5R9Z7, Q5RFV8, Q61XX9, Q64702, Q66HB5, Q68FF0, Q6DTM3, Q6EEF3, Q6EMB2, Q6NSI8, Q6S5J6, Q6TNJ1, Q6ZT98, Q8BRB7, Q8CDA1, Q8CDM1, Q8CDP0, Q8K3E5, Q8N157

Diamond homologs: A0A8C0TYJ0, A0A8P0N4K0, A5PKA5, F1MCA7, G5ECY0, O14907, O14910, O35274, O35867, O55164, O61967, O62674, O62675, O62676, O88951, O88952, P31016, P57105, P70175, P70587, P78352, P97879, Q0P5E6, Q0P5F3, Q12959, Q13424, Q13425, Q13884, Q14160, Q15599, Q22638, Q28626, Q28C55, Q2KIB6, Q32LE7, Q32LM6, Q3T0C9, Q3UHD6, Q4H4B6, Q5EBL8

SIGNOR signaling

0 interactions.

Enriched among interaction partners

Reactome pathways and GO biological processes over-represented among this gene’s 82 IntAct physical interaction partners (hypergeometric vs the genome-wide background, BH-FDR, gene-set size 15–500, ranked by fold). A functional readout of the neighbourhood — distinct from this gene’s own memberships above, and biased toward well-studied / hub proteins, so read it as themes rather than proof.

Reactome pathways:

PathwayPartnersFoldFDR
Translocation of SLC2A4 (GLUT4) to the plasma membrane513.5×4e-03

GO biological processes:

GO termPartnersFoldFDR
establishment or maintenance of epithelial cell apical/basal polarity754.2×3e-08
establishment or maintenance of cell polarity632.1×9e-06
establishment of cell polarity630.6×9e-06
small GTPase-mediated signal transduction614.7×6e-04
transmembrane transport511.2×6e-03
regulation of actin cytoskeleton organization510.5×7e-03
actin filament organization69.5×4e-03
intracellular protein localization68.4×6e-03

Disease & clinical

Clinical variants and AI predictions

ClinVar

50 variants total. Per-class counts are floors (≥ shown; pagination cap):

ClassificationCount (floor)
Pathogenic0
Likely pathogenic0
Uncertain significance37
Likely benign1
Benign1

Top pathogenic / likely-pathogenic (0)

SpliceAI

541 predictions. Top by Δscore:

VariantEffectΔscore
20:50737854:TAGT:Tacceptor_loss1.0000
20:50737855:A:AGacceptor_gain1.0000
20:50737855:AGTTT:Aacceptor_gain1.0000
20:50737856:G:GAacceptor_gain1.0000
20:50737856:GT:Gacceptor_gain1.0000
20:50737856:GTTT:Gacceptor_gain1.0000
20:50737856:GTTTG:Gacceptor_gain1.0000
20:50738075:GAAGG:Gdonor_gain1.0000
20:50738079:GGT:Gdonor_loss1.0000
20:50738080:G:GGdonor_gain1.0000
20:50738080:GT:Gdonor_loss1.0000
20:50738081:T:Adonor_loss1.0000
20:50731838:G:GTdonor_gain0.9900
20:50731850:AAGGT:Adonor_loss0.9900
20:50731851:AGG:Adonor_loss0.9900
20:50731853:G:GAdonor_loss0.9900
20:50738076:AAGG:Adonor_gain0.9900
20:50738078:GG:Gdonor_gain0.9900
20:50738079:GG:Gdonor_gain0.9900
20:50738082:AAGTA:Adonor_loss0.9900
20:50738083:AGTAT:Adonor_loss0.9900
20:50749657:A:AGacceptor_gain0.9900
20:50749658:G:GGacceptor_gain0.9900
20:50749658:GAA:Gacceptor_gain0.9900
20:50731848:GCAAG:Gdonor_gain0.9800
20:50737832:A:Gacceptor_gain0.9800
20:50737854:T:Gacceptor_gain0.9800
20:50737856:GTT:Gacceptor_gain0.9800
20:50738077:AGG:Adonor_gain0.9800
20:50738078:GGG:Gdonor_gain0.9800

AlphaMissense

2469 scored. Top likely-pathogenic:

VariantProtein changeam_pathogenicity
20:50731846:G:CK20N1.000
20:50731846:G:TK20N1.000
20:50731847:A:CS21R1.000
20:50731849:C:AS21R1.000
20:50731849:C:GS21R1.000
20:50737869:T:CF27L1.000
20:50737870:T:CF27S1.000
20:50737871:T:AF27L1.000
20:50737871:T:GF27L1.000
20:50737872:C:AR28S1.000
20:50737873:G:CR28P1.000
20:50737875:C:GR29G1.000
20:50737878:T:CF30L1.000
20:50737879:T:CF30S1.000
20:50737880:T:AF30L1.000
20:50737880:T:GF30L1.000
20:50737918:T:CF43S1.000
20:50737930:T:CL47P1.000
20:50737941:C:GH51D1.000
20:50737999:T:CL70P1.000
20:50738005:T:AI72K1.000
20:50738005:T:CI72T1.000
20:50738005:T:GI72R1.000
20:50738022:T:GY78D1.000
20:50738031:G:CA81P1.000
20:50738032:C:AA81D1.000
20:50738056:T:AL89H1.000
20:50738056:T:CL89P1.000
20:50749784:T:CF139L1.000
20:50749786:T:AF139L1.000

dbSNP variants (sampled 300 via entrez): RS1000236645 (20:50752891 G>A,T), RS1000319496 (20:50731572 G>A), RS1000518289 (20:50731523 C>G), RS1000557746 (20:50737373 A>G,T), RS1000939239 (20:50737120 CTTCCTCCCCA>C), RS1000964714 (20:50754172 C>T), RS1000991593 (20:50736817 C>T), RS1001202877 (20:50745746 G>A), RS1001279534 (20:50743434 A>C), RS1001311750 (20:50730944 G>A,C), RS1001471238 (20:50749472 C>G), RS1001642921 (20:50751740 T>G), RS1001653247 (20:50734126 A>C), RS1001763295 (20:50740520 G>A), RS1001884416 (20:50742055 GTGTTT>G,GTGTTTTGTTT)

Disease associations

OMIM: gene MIM:608975 | disease phenotypes:

GenCC curated gene-disease

Mondo (0):

Orphanet (0):

HPO phenotypes

0 total (0 of 0 shown, HPO-id order):

GWAS associations

1 associations (top):

StudyTraitp-value
GCST001164_2Bipolar disorder3.000000e-06

Drugs & pharmacology

Drug and pharmacology data

Is drug target: no

PharmGKB: 1 entry (VIP=true, CPIC=false)

CTD chemical–gene interactions

50 total (human), top 30 by PubMed support.

ChemicalActions (top 5)PubMed papers
Benzo(a)pyreneaffects methylation, increases expression4
trichostatin Aaffects cotreatment, decreases expression3
ochratoxin Aincreases expression, decreases expression2
Air Pollutantsincreases abundance, affects expression, affects cotreatment, decreases expression2
Ozoneincreases abundance, affects expression, affects cotreatment, decreases expression2
Valproic Acidaffects cotreatment, decreases expression2
aristolochic acid Idecreases expression1
methylmercuric chloridedecreases expression1
alpha-pinenedecreases expression, increases abundance, affects cotreatment1
bis(tri-n-butyltin)oxideincreases expression1
bisphenol Aincreases expression1
testosterone undecanoateaffects cotreatment, decreases expression1
2-methyl-4-isothiazolin-3-oneincreases expression1
tributyltinincreases expression1
cobaltous chlorideincreases expression1
methylmercury IIincreases expression1
methacrylaldehydeincreases abundance, affects cotreatment, decreases expression1
di-n-butylphosphoric acidaffects expression1
CGP 52608affects binding, increases reaction1
4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamideaffects cotreatment, decreases expression1
abrineincreases expression1
dorsomorphinaffects cotreatment, decreases expression1
1-(4-(6-bromobenzo(1,3)dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta(c)quinolin-8-yl)ethanoneincreases phosphorylation1
asparanin Adecreases expression1
jinfukangdecreases expression1
NSC 689534affects binding, increases expression1
Sunitinibdecreases expression1
Leflunomideincreases expression1
Acroleinaffects cotreatment, decreases expression, increases abundance1
Amphotericin Bincreases expression1

Clinical trials (associated diseases)

0 trials via MONDO — disease-level, not drug-specific.

No linked Atlas pages yet — the cross-entity mesh grows as the corpus expands.