OR4K2

Summary

OR4K2 (olfactory receptor family 4 subfamily K member 2, HGNC:14728) is a protein-coding gene on chromosome 14q11.2, encoding Olfactory receptor 4K2 (Q8NGD2). Odorant receptor.

Olfactory receptors interact with odorant molecules in the nose, to initiate a neuronal response that triggers the perception of a smell. The olfactory receptor proteins are members of a large family of G-protein-coupled receptors (GPCR) arising from single coding-exon genes. Olfactory receptors share a 7-transmembrane domain structure with many neurotransmitter and hormone receptors and are responsible for the recognition and G protein-mediated transduction of odorant signals. The olfactory receptor gene family is the largest in the genome.

Source: NCBI Gene 390431 — RefSeq curated summary.

At a glance

• Clinical variants (ClinVar): 61 total
• MANE Select transcript: NM_001005501

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:14728
Approved symbol	OR4K2
Name	olfactory receptor family 4 subfamily K member 2
Location	14q11.2
Locus type	gene with protein product
Status	Approved
Ensembl gene	ENSG00000165762
Ensembl biotype	protein_coding
Entrez	390431

Gene structure

Transcript identifiers

Ensembl transcripts: 4 — 2 protein_coding, 2 protein_coding_CDS_not_defined

ENST00000298642, ENST00000641522, ENST00000641785, ENST00000641885

RefSeq mRNA: 1 — MANE Select: NM_001005501 NM_001005501

CCDS: CCDS32023

Canonical transcript exons

ENST00000641885 — 2 exons

Exon	Start	End
ENSE00003813115	19875142	19876134
ENSE00003813376	19876245	19883932

Expression profiles

Bgee: expression breadth tissue_specific, 3 present calls, max score 71.10.

Top tissues by expression

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

Tissue	Anatomy ID	Expression score	Quality
male germ line stem cell (sensu Vertebrata) in testis	CL:0000089 ∩ UBERON:0000473	71.10	silver quality
sural nerve	UBERON:0015488	53.29	gold quality
colonic epithelium	UBERON:0000397	49.31	gold quality
monocyte	CL:0000576	41.77	gold quality
blood	UBERON:0000178	41.06	gold quality
leukocyte	CL:0000738	40.96	gold quality
bone marrow	UBERON:0002371	40.27	gold quality
vermiform appendix	UBERON:0001154	40.22	gold quality
calcaneal tendon	UBERON:0003701	39.95	gold quality
ventricular zone	UBERON:0003053	39.82	gold quality
stromal cell of endometrium	CL:0002255	38.69	gold quality
lymph node	UBERON:0000029	37.71	gold quality
superior frontal gyrus	UBERON:0002661	37.48	gold quality
lower esophagus mucosa	UBERON:0035834	37.29	gold quality
muscle tissue	UBERON:0002385	37.22	silver quality
duodenum	UBERON:0002114	36.68	gold quality
cortical plate	UBERON:0005343	36.47	gold quality
uterine cervix	UBERON:0000002	36.29	gold quality
bone marrow cell	CL:0002092	36.16	gold quality
skeletal muscle tissue	UBERON:0001134	36.10	gold quality
liver	UBERON:0002107	35.72	silver quality
ganglionic eminence	UBERON:0004023	35.49	gold quality
endometrium	UBERON:0001295	35.43	gold quality
hindlimb stylopod muscle	UBERON:0004252	35.14	gold quality
apex of heart	UBERON:0002098	34.77	gold quality
granulocyte	CL:0000094	33.94	gold quality
mucosa of transverse colon	UBERON:0004991	33.73	gold quality
urinary bladder	UBERON:0001255	33.16	gold quality
right lobe of liver	UBERON:0001114	33.13	gold quality
smooth muscle tissue	UBERON:0001135	33.00	gold quality

Single-cell (SCXA)

Detected in 2 experiment(s), a significant marker in 1.

Experiment	Marker?	Max mean expression
E-ANND-3	yes	6.88
E-GEOD-110499	no	7.42

Regulation

Is transcription factor: no

Cross-species orthologs

2 orthologs

Organism	Symbol	Gene ID
mus_musculus	Or4k2	ENSMUSG00000109835
rattus_norvegicus	Or4k2	ENSRNOG00000076166

Paralogs (130): OR1I1 (ENSG00000094661), OR12D3 (ENSG00000112462), OR7A10 (ENSG00000127515), OR7C2 (ENSG00000127529), OR7C1 (ENSG00000127530), OR1E2 (ENSG00000127780), OR1J1 (ENSG00000136834), OR1L4 (ENSG00000136939), OR4D1 (ENSG00000141194), OR4K1 (ENSG00000155249), OR3A3 (ENSG00000159961), OR7G1 (ENSG00000161807), OR1Q1 (ENSG00000165202), OR1K1 (ENSG00000165204), OR4D6 (ENSG00000166884), OR1F1 (ENSG00000168124), OR4K14 (ENSG00000169484), OR4K15 (ENSG00000169488), OR7G3 (ENSG00000170920), OR7G2 (ENSG00000170923), OR1M1 (ENSG00000170929), OR4D5 (ENSG00000171014), OR1L6 (ENSG00000171459), OR1L3 (ENSG00000171481), OR1L8 (ENSG00000171496), OR1N2 (ENSG00000171501), OR1N1 (ENSG00000171505), OR2AT4 (ENSG00000171561), OR1A1 (ENSG00000172146), OR1A2 (ENSG00000172150), OR4C11 (ENSG00000172188), OR4X2 (ENSG00000172208), OR4D9 (ENSG00000172742), OR10K1 (ENSG00000173285), OR1L1 (ENSG00000173679), OR7D4 (ENSG00000174667), OR4S2 (ENSG00000174982), OR4B1 (ENSG00000175619), OR4D11 (ENSG00000176200), OR4K17 (ENSG00000176230)

Protein

Protein identifiers

Olfactory receptor 4K2 — Q8NGD2 (reviewed: Q8NGD2)

Alternative names: Olfactory receptor OR14-15

All UniProt accessions (2): A0A126GVP5, Q8NGD2

UniProt curated annotations — full annotation on UniProt →

Function. Odorant receptor.

Subcellular location. Cell membrane.

Similarity. Belongs to the G-protein coupled receptor 1 family.

RefSeq proteins (1): NP_001005501* (*=MANE)

Domains & families (InterPro)

ID	Name	Type
IPR000276	GPCR_Rhodpsn	Family
IPR000725	Olfact_rcpt	Family
IPR017452	GPCR_Rhodpsn_7TM	Domain
IPR050427	Olfactory_Receptors	Family

Pfam: PF13853

UniProt features (19 total): topological domain 8, transmembrane region 7, chain 1, glycosylation site 1, disulfide bond 1, sequence variant 1

Structure

Experimental structures (PDB)

0 structures.

Predicted structure (AlphaFold)

Model	pLDDT	Fraction very-high
AF-Q8NGD2-F1	86.19	0.45

Functional residue map

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

Disulfide bonds (1): 97–189

Glycosylation sites (1): 5

Function

Pathways and Gene Ontology

Reactome pathways

1 pathways

ID	Pathway
R-HSA-9752946	Expression and translocation of olfactory receptors

MSigDB gene sets: 20 (showing top): GOBP_SENSORY_PERCEPTION_OF_CHEMICAL_STIMULUS, KEGG_OLFACTORY_TRANSDUCTION, GOBP_DETECTION_OF_STIMULUS, GOBP_SENSORY_PERCEPTION, ACEVEDO_LIVER_CANCER_WITH_H3K27ME3_DN, GOMF_OLFACTORY_RECEPTOR_ACTIVITY, GOMF_TRANSMEMBRANE_SIGNALING_RECEPTOR_ACTIVITY, GOMF_G_PROTEIN_COUPLED_RECEPTOR_ACTIVITY, GOBP_SENSORY_PERCEPTION_OF_SMELL, GOBP_G_PROTEIN_COUPLED_RECEPTOR_SIGNALING_PATHWAY, GOBP_DETECTION_OF_STIMULUS_INVOLVED_IN_SENSORY_PERCEPTION, SRSF9_TARGET_GENES, REACTOME_OLFACTORY_SIGNALING_PATHWAY, REACTOME_SENSORY_PERCEPTION, ZHANG_FH_DEFICIENT_RCC_C2_VS_OTHERS_UP

GO Biological Process (4): signal transduction (GO:0007165), G protein-coupled receptor signaling pathway (GO:0007186), sensory perception of smell (GO:0007608), detection of chemical stimulus involved in sensory perception of smell (GO:0050911)

GO Molecular Function (2): G protein-coupled receptor activity (GO:0004930), olfactory receptor activity (GO:0004984)

GO Cellular Component (2): plasma membrane (GO:0005886), membrane (GO:0016020)

Reactome top-level categories

Rollup of top-1 pathways:

Category	Pathways
Olfactory Signaling Pathway	1

GO top-level categories

Rollup of top GO terms by namespace:

Category	Terms
transmembrane signaling receptor activity	2
cell communication	1
cellular process	1
signaling	1
regulation of cellular process	1
cellular response to stimulus	1
G protein-coupled receptor activity	1
signal transduction	1
sensory perception of chemical stimulus	1
sensory perception of smell	1
detection of chemical stimulus involved in sensory perception	1
G protein-coupled receptor signaling pathway	1
detection of chemical stimulus involved in sensory perception of smell	1
membrane	1
cell periphery	1
cellular anatomical structure	1

Protein interactions and networks

STRING

190 interactions, top by confidence (×1000):

Protein A	Protein B	Partner UniProt	Score
OR4K2	POM121L12	Q8N7R1	519
OR4K2	ZNF543	Q08ER8	480
OR4K2	ARMCX5	Q6P1M9	431
OR4K2	PCDHB6	Q9Y5E3	418
OR4K2	PCDHB15	Q9Y5E8	418
OR4K2	PCDHB10	Q9UN67	416
OR4K2	PCDHB1	Q9Y5F3	410
OR4K2	PCDHB3	Q9Y5E6	406
OR4K2	PCDHB5	Q9Y5E4	400
OR4K2	POTEM	A6NI47	399
OR4K2	UGT2B10	P36537	395
OR4K2	OR4M1	Q8NGD0	393
OR4K2	OR4Q3	Q8NH05	380
OR4K2	ELAPOR2	A8MWY0	370
OR4K2	TGS1	Q96RS0	367

IntAct

0 interactions, top by confidence:

BioGRID (1): OR4K2 (Affinity Capture-MS)

ESM2 similar proteins: A0A096LPK9, A0A0X1KG70, A6NHA9, A6NMZ5, P0C604, P0C623, P0C645, P0DN82, P58180, P58182, Q15615, Q60881, Q6IF82, Q8IXE1, Q8N0Y3, Q8NGA8, Q8NGB4, Q8NGB6, Q8NGC2, Q8NGC3, Q8NGD0, Q8NGD1, Q8NGD2, Q8NGD5, Q8NGE8, Q8NGF4, Q8NGF8, Q8NGF9, Q8NGI4, Q8NGI6, Q8NGJ0, Q8NGJ1, Q8NGL6, Q8NGM1, Q8NGN0, Q8NGN8, Q8NGX5, Q8NH05, Q8NH42, Q8NH49

Diamond homologs: A0A096LPK9, A0A0X1KG70, A6NHA9, A6NMZ5, O60412, O76099, O95013, P0C604, P0C623, P0C645, P0DN82, P23270, P23275, P58173, P58180, P58182, Q15615, Q60878, Q60881, Q60888, Q6IEV9, Q6IEY1, Q6IF82, Q7TQQ0, Q8IXE1, Q8N0Y3, Q8N628, Q8NGA8, Q8NGB2, Q8NGB4, Q8NGB6, Q8NGB8, Q8NGB9, Q8NGC2, Q8NGC3, Q8NGC4, Q8NGC6, Q8NGD0, Q8NGD1, Q8NGD2

SIGNOR signaling

0 interactions.

Disease & clinical

Clinical variants and AI predictions

ClinVar

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

Classification	Count (floor)
Pathogenic	0
Likely pathogenic	0
Uncertain significance	59
Likely benign	2
Benign	0

Top pathogenic / likely-pathogenic (0)

SpliceAI

178 predictions. Top by Δscore:

Variant	Effect	Δscore
14:19876277:GGCAA:G	donor_gain	0.8300
14:19876278:GCAA:G	donor_gain	0.8100
14:19876281:A:AG	donor_gain	0.7200
14:19876921:T:G	acceptor_gain	0.6500
14:19876331:G:T	donor_gain	0.6400
14:19876270:GGAT:G	donor_gain	0.6300
14:19876271:GATG:G	donor_gain	0.6300
14:19876281:A:G	donor_gain	0.6300
14:19876330:GGAAC:G	donor_gain	0.6200
14:19876385:G:GG	donor_gain	0.6200
14:19876381:AATGG:A	donor_loss	0.5900
14:19876382:ATGGT:A	donor_loss	0.5900
14:19876383:TGG:T	donor_loss	0.5900
14:19876932:T:TA	acceptor_gain	0.5900
14:19876386:T:A	donor_loss	0.5800
14:19876388:GGTAA:G	donor_loss	0.5800
14:19877020:T:A	acceptor_gain	0.5800
14:19876271:GAT:G	donor_gain	0.5700
14:19876331:G:GT	donor_gain	0.5700
14:19876387:GGGTA:G	donor_loss	0.5700
14:19876239:A:AG	donor_gain	0.5600
14:19876389:G:C	donor_loss	0.5500
14:19877021:G:A	acceptor_gain	0.5500
14:19876274:G:GG	donor_gain	0.5400
14:19876919:T:G	acceptor_gain	0.5300
14:19876273:T:G	donor_gain	0.5200
14:19876277:G:A	donor_gain	0.5200
14:19876271:G:T	donor_gain	0.5100
14:19876293:T:G	donor_gain	0.5100
14:19876440:C:G	donor_gain	0.5100

AlphaMissense

2091 scored. Top likely-pathogenic:

Variant	Protein change	am_pathogenicity
14:19877018:T:C	F251L	0.923
14:19877020:T:A	F251L	0.923
14:19877020:T:G	F251L	0.923
14:19876769:T:C	F168L	0.908
14:19876771:C:A	F168L	0.908
14:19876771:C:G	F168L	0.908
14:19876301:T:C	F12L	0.905
14:19876303:T:A	F12L	0.905
14:19876303:T:G	F12L	0.905
14:19876796:T:C	F177L	0.872
14:19876798:T:A	F177L	0.872
14:19876798:T:G	F177L	0.872
14:19876799:T:C	F178L	0.868
14:19876801:C:A	F178L	0.868
14:19876801:C:G	F178L	0.868
14:19876874:A:C	S203R	0.855
14:19876876:T:A	S203R	0.855
14:19876876:T:G	S203R	0.855
14:19876358:T:C	F31L	0.847
14:19876360:T:A	F31L	0.847
14:19876360:T:G	F31L	0.847
14:19876739:A:C	S158R	0.839
14:19876741:T:A	S158R	0.839
14:19876741:T:G	S158R	0.839
14:19876493:T:C	F76L	0.834
14:19876495:C:A	F76L	0.834
14:19876495:C:G	F76L	0.834
14:19877015:T:C	F250L	0.833
14:19877017:C:A	F250L	0.833
14:19877017:C:G	F250L	0.833

dbSNP variants (sampled 300 via entrez): RS1000138283 (14:19878512 T>C), RS1000429506 (14:19881292 A>G,T), RS1000782403 (14:19881470 T>C), RS1001059434 (14:19875086 C>T), RS1001173437 (14:19877958 T>G), RS1001187403 (14:19877432 T>C), RS1002112635 (14:19874353 C>G), RS1002276993 (14:19878811 G>A), RS1002386860 (14:19883507 G>A), RS1003307708 (14:19874325 A>G), RS1003648087 (14:19883636 A>C), RS1003687161 (14:19879992 A>G), RS1004281959 (14:19881038 C>A,G,T), RS1004559361 (14:19875499 T>C,G), RS1005125441 (14:19877479 G>C,T)

Disease associations

OMIM: gene `` | disease phenotypes:

GenCC curated gene-disease

Mondo (0):

Orphanet (0):

HPO phenotypes

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

GWAS associations

0 associations (top):

Drugs & pharmacology

Drug and pharmacology data

Is drug target: no

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

CTD chemical–gene interactions

6 total (human), top 6 by PubMed support.

Chemical	Actions (top 5)	PubMed papers
Air Pollutants, Occupational	increases expression	1
Benzo(a)pyrene	decreases methylation	1
Nickel	increases expression	1
Phthalic Acids	increases methylation	1
Aflatoxin B1	decreases methylation	1
Sodium Selenite	increases expression	1

Clinical trials (associated diseases)

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