Seroatlas · Human Serome Atlas

NAPG

Gamma-soluble NSF attachment protein

Also known as: SNAG_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q99747
Gene
NAPG
Ensembl
ENSG00000134265
Chromosome
18
Canonical length
312 aa
Protein class
Predicted intracellular proteins
Subcellular location
Plasma membrane

OverviewNCBI Gene

This gene encodes soluble NSF attachment protein gamma. The soluble NSF attachment proteins (SNAPs) enable N-ethyl-maleimide-sensitive fusion protein (NSF) to bind to target membranes. NSF and SNAPs appear to be general components of the intracellular membrane fusion apparatus, and their action at specific sites of fusion must be controlled by SNAP receptors particular to the membranes being fused. The product of this gene mediates platelet exocytosis and controls the membrane fusion events of this process.[provided by RefSeq, Dec 2008]

Canonical amino-acid sequenceUniProt

312 residues, UniProt reviewed canonical sequence.

>Q99747|NAPG
     1  MAAQKINEGL EHLAKAEKYL KTGFLKWKPD YDSAASEYGK AAVAFKNAKQ FEQAKDACLR
    61  EAVAHENNRA LFHAAKAYEQ AGMMLKEMQK LPEAVQLIEK ASMMYLENGT PDTAAMALER
   121  AGKLIENVDP EKAVQLYQQT ANVFENEERL RQAVELLGKA SRLLVRGRRF DEAALSIQKE
   181  KNIYKEIENY PTCYKKTIAQ VLVHLHRNDY VAAERCVRES YSIPGFNGSE DCAALEQLLE
   241  GYDQQDQDQV SDVCNSPLFK YMDNDYAKLG LSLVVPGGGI KKKSPATPQA KPDGVTATAA
   301  DEEEDEYSGG LC

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NAPG 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
30 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 30 nTPM
  • spinal cord: 27 nTPM
  • hippocampal formation: 25 nTPM
  • cerebellum: 24 nTPM
  • midbrain: 23 nTPM
  • basal ganglia: 22 nTPM

Single-cell type

  • esophageal apical cells: 147 nCPM
  • conjunctival goblet cells: 132 nCPM
  • respiratory ionocytes: 130 nCPM
  • esophageal suprabasal cells: 106 nCPM
  • urothelial cells: 102 nCPM
  • endometrial secretory cells: 101 nCPM

Immune cell

  • eosinophil: 14 nTPM
  • basophil: 13 nTPM
  • neutrophil: 8.4 nTPM
  • memory B-cell: 7.7 nTPM
  • non-classical monocyte: 6.7 nTPM
  • intermediate monocyte: 6.6 nTPM

Brain region

  • pons: 51 nTPM
  • medulla oblongata: 38 nTPM
  • hippocampal formation: 38 nTPM
  • cerebral cortex: 30 nTPM
  • white matter: 30 nTPM
  • cerebellum: 27 nTPM

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)
0.55
gnomAD pLI
0.08
gnomAD missense Z
0.57
DepMap mean gene effect
-0.75
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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 NAPG 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 NAPG as an antibody target. Whether an autoantibody or antibody against NAPG could matter depends on whether native NAPG is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NAPG is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

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

Canonical record: https://seroatlas.com/gene/NAPG. 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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