Seroatlas · Human Serome Atlas

GAP43

Neuromodulin

Also known as: B-50, GAP-43, NEUM_HUMAN, PP46

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

Protein identityUniProt · HPA

UniProt accession
P17677
Gene
GAP43
Ensembl
ENSG00000172020
Chromosome
3
Canonical length
238 aa
Protein class
Plasma proteins, Predicted intracellular proteins, Transporters
Subcellular location
Plasma membrane

OverviewNCBI Gene

The protein encoded by this gene has been termed a 'growth' or 'plasticity' protein because it is expressed at high levels in neuronal growth cones during development and axonal regeneration. This protein is considered a crucial component of an effective regenerative response in the nervous system. Alternatively spliced transcript variants encoding distinct isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

238 residues, UniProt reviewed canonical sequence.

>P17677|GAP43
     1  MLCCMRRTKQ VEKNDDDQKI EQDGIKPEDK AHKAATKIQA SFRGHITRKK LKGEKKDDVQ
    61  AAEAEANKKD EAPVADGVEK KGEGTTTAEA APATGSKPDE PGKAGETPSE EKKGEGDAAT
   121  EQAAPQAPAS SEEKAGSAET ESATKASTDN SPSSKAEDAP AKEEPKQADV PAAVTAAAAT
   181  TPAAEDAAAK ATAQPPTETG ESSQAEENIE AVDETKPKES ARQDEGKEEE PEADQEHA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against GAP43 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)
0.69
Highest tissue expression
474 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 474 nTPM
  • hypothalamus: 310 nTPM
  • amygdala: 275 nTPM
  • basal ganglia: 211 nTPM
  • cerebellum: 187 nTPM
  • midbrain: 162 nTPM

Single-cell type

  • other brain neurons: 249 nCPM
  • brain excitatory neurons: 235 nCPM
  • brain inhibitory neurons: 149 nCPM
  • retinal pigment epithelial cells: 81 nCPM
  • pituicytes/fscs: 71 nCPM
  • oligodendrocyte progenitor cells: 55 nCPM

Immune cell

  • naive CD8 T-cell: 0.2 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM

Brain region

  • cerebral cortex: 623 nTPM
  • hypothalamus: 452 nTPM
  • midbrain: 386 nTPM
  • thalamus: 370 nTPM
  • basal ganglia: 334 nTPM
  • white matter: 297 nTPM

ReferencesPubMed · IEDB

Publications for GAP43 from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

2 publications

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)
1
gnomAD pLI
0.02
gnomAD missense Z
-0.07
DepMap mean gene effect
0.13
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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads GAP43 as an antibody target. Whether an autoantibody or antibody against GAP43 could matter depends on whether native GAP43 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

GAP43 is annotated at the cell surface, where native GAP43 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 GAP43 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/GAP43. 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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