Seroatlas · Human Serome Atlas

AP2A1

AP-2 complex subunit alpha-1

Also known as: ADTAA, AP2A1_HUMAN, CLAPA1

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

Protein identityUniProt · HPA

UniProt accession
O95782
Gene
AP2A1
Ensembl
ENSG00000196961
Chromosome
19
Canonical length
977 aa
Protein class
Predicted intracellular proteins, Transporters
Subcellular location
Vesicles

OverviewNCBI Gene

This gene encodes the alpha 1 adaptin subunit of the adaptor protein 2 (AP-2) complex found in clathrin coated vesicles. The AP-2 complex is a heterotetramer consisting of two large adaptins (alpha or beta), a medium adaptin (mu), and a small adaptin (sigma). The complex is part of the protein coat on the cytoplasmic face of coated vesicles which links clathrin to receptors in vesicles. Alternative splicing of this gene results in two transcript variants encoding two different isoforms. A third transcript variant has been described, but its full length nature has not been determined. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

977 residues, UniProt reviewed canonical sequence.

>O95782|AP2A1
     1  MPAVSKGDGM RGLAVFISDI RNCKSKEAEI KRINKELANI RSKFKGDKAL DGYSKKKYVC
    61  KLLFIFLLGH DIDFGHMEAV NLLSSNKYTE KQIGYLFISV LVNSNSELIR LINNAIKNDL
   121  ASRNPTFMCL ALHCIANVGS REMGEAFAAD IPRILVAGDS MDSVKQSAAL CLLRLYKASP
   181  DLVPMGEWTA RVVHLLNDQH MGVVTAAVSL ITCLCKKNPD DFKTCVSLAV SRLSRIVSSA
   241  STDLQDYTYY FVPAPWLSVK LLRLLQCYPP PEDAAVKGRL VECLETVLNK AQEPPKSKKV
   301  QHSNAKNAIL FETISLIIHY DSEPNLLVRA CNQLGQFLQH RETNLRYLAL ESMCTLASSE
   361  FSHEAVKTHI DTVINALKTE RDVSVRQRAA DLLYAMCDRS NAKQIVSEML RYLETADYAI
   421  REEIVLKVAI LAEKYAVDYS WYVDTILNLI RIAGDYVSEE VWYRVLQIVT NRDDVQGYAA
   481  KTVFEALQAP ACHENMVKVG GYILGEFGNL IAGDPRSSPP VQFSLLHSKF HLCSVATRAL
   541  LLSTYIKFIN LFPETKATIQ GVLRAGSQLR NADVELQQRA VEYLTLSSVA STDVLATVLE
   601  EMPPFPERES SILAKLKRKK GPGAGSALDD GRRDPSSNDI NGGMEPTPST VSTPSPSADL
   661  LGLRAAPPPA APPASAGAGN LLVDVFDGPA AQPSLGPTPE EAFLSELEPP APESPMALLA
   721  DPAPAADPGP EDIGPPIPEA DELLNKFVCK NNGVLFENQL LQIGVKSEFR QNLGRMYLFY
   781  GNKTSVQFQN FSPTVVHPGD LQTQLAVQTK RVAAQVDGGA QVQQVLNIEC LRDFLTPPLL
   841  SVRFRYGGAP QALTLKLPVT INKFFQPTEM AAQDFFQRWK QLSLPQQEAQ KIFKANHPMD
   901  AEVTKAKLLG FGSALLDNVD PNPENFVGAG IIQTKALQVG CLLRLEPNAQ AQMYRLTLRT
   961  SKEPVSRHLC ELLAQQF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AP2A1 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)
0.31
Highest tissue expression
85 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 85 nTPM
  • testis: 85 nTPM
  • adrenal gland: 84 nTPM
  • cerebral cortex: 79 nTPM
  • cerebellum: 68 nTPM
  • ovary: 55 nTPM

Single-cell type

  • syncytiotrophoblasts: 355 nCPM
  • late spermatids: 222 nCPM
  • cytotrophoblasts: 137 nCPM
  • early spermatids: 133 nCPM
  • late primary spermatocytes: 120 nCPM
  • erythrocyte progenitors: 117 nCPM

Immune cell

  • non-classical monocyte: 21 nTPM
  • intermediate monocyte: 13 nTPM
  • classical monocyte: 5.3 nTPM
  • total PBMC: 4.8 nTPM
  • myeloid DC: 4.7 nTPM
  • neutrophil: 4 nTPM

Brain region

  • thalamus: 150 nTPM
  • cerebral cortex: 145 nTPM
  • pons: 139 nTPM
  • amygdala: 123 nTPM
  • hippocampal formation: 119 nTPM
  • basal ganglia: 119 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)
0.1
gnomAD pLI
1
gnomAD missense Z
4.4
DepMap mean gene effect
-0.03
DepMap dependency class
selective

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 AP2A1 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 AP2A1 as an antibody target. Whether an autoantibody or antibody against AP2A1 could matter depends on whether native AP2A1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

AP2A1 is annotated at the cell surface, where native AP2A1 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 AP2A1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/AP2A1. 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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