Seroatlas · Human Serome Atlas

NOS3

Nitric oxide synthase 3

Also known as: ECNOS, eNOS, NOS3_HUMAN

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P29474
Gene
NOS3
Ensembl
ENSG00000164867
Chromosome
7
Canonical length
1203 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, FDA approved drug targets, Human disease related genes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins
Quaternary structure
Homodimer

OverviewNCBI Gene

Nitric oxide is a reactive free radical which acts as a biologic mediator in several processes, including neurotransmission and antimicrobial and antitumoral activities. Nitric oxide is synthesized from L-arginine by nitric oxide synthases. Variations in this gene are associated with susceptibility to coronary spasm. Alternative splicing and the use of alternative promoters results in multiple transcript variants. [provided by RefSeq, Oct 2016]

Canonical amino-acid sequenceUniProt

1203 residues, UniProt reviewed canonical sequence.

>P29474|NOS3
     1  MGNLKSVAQE PGPPCGLGLG LGLGLCGKQG PATPAPEPSR APASLLPPAP EHSPPSSPLT
    61  QPPEGPKFPR VKNWEVGSIT YDTLSAQAQQ DGPCTPRRCL GSLVFPRKLQ GRPSPGPPAP
   121  EQLLSQARDF INQYYSSIKR SGSQAHEQRL QEVEAEVAAT GTYQLRESEL VFGAKQAWRN
   181  APRCVGRIQW GKLQVFDARD CRSAQEMFTY ICNHIKYATN RGNLRSAITV FPQRCPGRGD
   241  FRIWNSQLVR YAGYRQQDGS VRGDPANVEI TELCIQHGWT PGNGRFDVLP LLLQAPDDPP
   301  ELFLLPPELV LEVPLEHPTL EWFAALGLRW YALPAVSNML LEIGGLEFPA APFSGWYMST
   361  EIGTRNLCDP HRYNILEDVA VCMDLDTRTT SSLWKDKAAV EINVAVLHSY QLAKVTIVDH
   421  HAATASFMKH LENEQKARGG CPADWAWIVP PISGSLTPVF HQEMVNYFLS PAFRYQPDPW
   481  KGSAAKGTGI TRKKTFKEVA NAVKISASLM GTVMAKRVKA TILYGSETGR AQSYAQQLGR
   541  LFRKAFDPRV LCMDEYDVVS LEHETLVLVV TSTFGNGDPP ENGESFAAAL MEMSGPYNSS
   601  PRPEQHKSYK IRFNSISCSD PLVSSWRRKR KESSNTDSAG ALGTLRFCVF GLGSRAYPHF
   661  CAFARAVDTR LEELGGERLL QLGQGDELCG QEEAFRGWAQ AAFQAACETF CVGEDAKAAA
   721  RDIFSPKRSW KRQRYRLSAQ AEGLQLLPGL IHVHRRKMFQ ATIRSVENLQ SSKSTRATIL
   781  VRLDTGGQEG LQYQPGDHIG VCPPNRPGLV EALLSRVEDP PAPTEPVAVE QLEKGSPGGP
   841  PPGWVRDPRL PPCTLRQALT FFLDITSPPS PQLLRLLSTL AEEPREQQEL EALSQDPRRY
   901  EEWKWFRCPT LLEVLEQFPS VALPAPLLLT QLPLLQPRYY SVSSAPSTHP GEIHLTVAVL
   961  AYRTQDGLGP LHYGVCSTWL SQLKPGDPVP CFIRGAPSFR LPPDPSLPCI LVGPGTGIAP
  1021  FRGFWQERLH DIESKGLQPT PMTLVFGCRC SQLDHLYRDE VQNAQQRGVF GRVLTAFSRE
  1081  PDNPKTYVQD ILRTELAAEV HRVLCLERGH MFVCGDVTMA TNVLQTVQRI LATEGDMELD
  1141  EAGDVIGVLR DQQRYHEDIF GLTLRTQEVT SRIRTQSFSL QERQLRGAVP WAFDPPGSDT
  1201  NSP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NOS3 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
59 nTPM

Expression across tissuesHPA

Tissue

  • spleen: 59 nTPM
  • heart muscle: 20 nTPM
  • adipose tissue: 18 nTPM
  • kidney: 18 nTPM
  • breast: 13 nTPM
  • blood vessel: 11 nTPM

Single-cell type

  • early spermatids: 96 nCPM
  • late primary spermatocytes: 61 nCPM
  • vascular endothelial cells: 56 nCPM
  • late spermatids: 48 nCPM
  • syncytiotrophoblasts: 29 nCPM
  • lymphatic endothelial cells: 28 nCPM

Immune cell

  • naive CD4 T-cell: 2.3 nTPM
  • T-reg: 2.1 nTPM
  • memory CD4 T-cell: 1.7 nTPM
  • gdT-cell: 1.1 nTPM
  • memory CD8 T-cell: 0.9 nTPM
  • naive CD8 T-cell: 0.9 nTPM

Brain region

  • thalamus: 25 nTPM
  • medulla oblongata: 20 nTPM
  • pons: 20 nTPM
  • amygdala: 19 nTPM
  • midbrain: 18 nTPM
  • spinal cord: 17 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about NOS3.

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 294 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.5
gnomAD pLI
0
gnomAD missense Z
2.04
DepMap mean gene effect
0.02
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of NOS3 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads NOS3 as an antibody target. Whether an autoantibody or antibody against NOS3 could matter depends on whether native NOS3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NOS3 is annotated at the cell surface, where native NOS3 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label NOS3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/NOS3. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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