Seroatlas · Human Serome Atlas

NAPA

Alpha-soluble NSF attachment protein

Also known as: SNAA_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P54920
Gene
NAPA
Ensembl
ENSG00000105402
Chromosome
19
Canonical length
295 aa
Protein class
Predicted intracellular proteins
Subcellular location
Cytosol

OverviewNCBI Gene

This gene encodes a member of the soluble NSF attachment protein (SNAP) family. SNAP proteins play a critical role in the docking and fusion of vesicles to target membranes as part of the 20S NSF-SNAP-SNARE complex. The encoded protein plays a role in the completion of membrane fusion by mediating the interaction of N-ethylmaleimide-sensitive factor (NSF) with the vesicle-associated and membrane-associated SNAP receptor (SNARE) complex, and stimulating the ATPase activity of NSF. Alternatively spliced transcript variants have been observed for this gene. [provided by RefSeq, Jun 2011]

Canonical amino-acid sequenceUniProt

295 residues, UniProt reviewed canonical sequence.

>P54920|NAPA
     1  MDNSGKEAEA MALLAEAERK VKNSQSFFSG LFGGSSKIEE ACEIYARAAN MFKMAKNWSA
    61  AGNAFCQAAQ LHLQLQSKHD AATCFVDAGN AFKKADPQEA INCLMRAIEI YTDMGRFTIA
   121  AKHHISIAEI YETELVDIEK AIAHYEQSAD YYKGEESNSS ANKCLLKVAG YAALLEQYQK
   181  AIDIYEQVGT NAMDSPLLKY SAKDYFFKAA LCHFCIDMLN AKLAVQKYEE LFPAFSDSRE
   241  CKLMKKLLEA HEEQNVDSYT ESVKEYDSIS RLDQWLTTML LRIKKTIQGD EEDLR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NAPA 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)
0.27
Highest tissue expression
209 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 209 nTPM
  • skeletal muscle: 195 nTPM
  • liver: 176 nTPM
  • cerebral cortex: 175 nTPM
  • adrenal gland: 163 nTPM
  • skin: 145 nTPM

Single-cell type

  • neutrophils: 180 nCPM
  • cone photoreceptor cells: 141 nCPM
  • colonocytes: 137 nCPM
  • enterocytes: 133 nCPM
  • esophageal apical cells: 132 nCPM
  • neuroendocrine cells: 111 nCPM

Immune cell

  • eosinophil: 314 nTPM
  • plasmacytoid DC: 210 nTPM
  • total PBMC: 209 nTPM
  • non-classical monocyte: 202 nTPM
  • basophil: 197 nTPM
  • intermediate monocyte: 190 nTPM

Brain region

  • cerebral cortex: 207 nTPM
  • hippocampal formation: 166 nTPM
  • pons: 157 nTPM
  • cerebellum: 137 nTPM
  • thalamus: 137 nTPM
  • white matter: 137 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)
0.51
gnomAD pLI
0.24
gnomAD missense Z
0.99
DepMap mean gene effect
-1.35
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 NAPA 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 NAPA as an antibody target. Whether an autoantibody or antibody against NAPA could matter depends on whether native NAPA is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NAPA is annotated at the cell surface, where native NAPA 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 NAPA as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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