Seroatlas · Human Serome Atlas

APBA1

Amyloid-beta A4 precursor protein-binding family A member 1

Also known as: APBA1_HUMAN, D9S411E, MINT1, X11

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

Protein identityUniProt · HPA

UniProt accession
Q02410
Gene
APBA1
Ensembl
ENSG00000107282
Chromosome
9
Canonical length
837 aa
Protein class
Predicted intracellular proteins, Transporters
Subcellular location
Golgi apparatus

OverviewNCBI Gene

The protein encoded by this gene is a member of the X11 protein family. It is a neuronal adapter protein that interacts with the Alzheimer's disease amyloid precursor protein (APP). It stabilizes APP and inhibits production of proteolytic APP fragments including the A beta peptide that is deposited in the brains of Alzheimer's disease patients. This gene product is believed to be involved in signal transduction processes. It is also regarded as a putative vesicular trafficking protein in the brain that can form a complex with the potential to couple synaptic vesicle exocytosis to neuronal cell adhesion. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

837 residues, UniProt reviewed canonical sequence.

>Q02410|APBA1
     1  MNHLEGSAEV EVTDEAAGGE VNESVEADLE HPEVEEEQQQ PPQQQHYVGR HQRGRALEDL
    61  RAQLGQEEEE RGECLARSAS TESGFHNHTD TAEGDVIAAA RDGYDAERAQ DPEDESAYAV
   121  QYRPEAEEYT EQAEAEHAEA THRRALPNHL HFHSLEHEEA MNAAYSGYVY THRLFHRGED
   181  EPYSEPYADY GGLQEHVYEE IGDAPELDAR DGLRLYEQER DEAAAYRQEA LGARLHHYDE
   241  RSDGESDSPE KEAEFAPYPR MDSYEQEEDI DQIVAEVKQS MSSQSLDKAA EDMPEAEQDL
   301  ERPPTPAGGR PDSPGLQAPA GQQRAVGPAG GGEAGQRYSK EKRDAISLAI KDIKEAIEEV
   361  KTRTIRSPYT PDEPKEPIWV MRQDISPTRD CDDQRPMDGD SPSPGSSSPL GAESSSTSLH
   421  PSDPVEASTN KESRKSLASF PTYVEVPGPC DPEDLIDGII FAANYLGSTQ LLSDKTPSKN
   481  VRMMQAQEAV SRIKMAQKLA KSRKKAPEGE SQPMTEVDLF ISTQRIKVLN ADTQETMMDH
   541  PLRTISYIAD IGNIVVLMAR RRMPRSNSQE NVEASHPSQD GKRQYKMICH VFESEDAQLI
   601  AQSIGQAFSV AYQEFLRANG INPEDLSQKE YSDLLNTQDM YNDDLIHFSK SENCKDVFIE
   661  KQKGEILGVV IVESGWGSIL PTVIIANMMH GGPAEKSGKL NIGDQIMSIN GTSLVGLPLS
   721  TCQSIIKGLK NQSRVKLNIV RCPPVTTVLI RRPDLRYQLG FSVQNGIICS LMRGGIAERG
   781  GVRVGHRIIE INGQSVVATP HEKIVHILSN AVGEIHMKTM PAAMYRLLTA QEQPVYI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against APBA1 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)
0.5
Highest tissue expression
35 nTPM

Expression across tissuesHPA

Tissue

  • cerebral cortex: 35 nTPM
  • amygdala: 32 nTPM
  • hypothalamus: 30 nTPM
  • basal ganglia: 28 nTPM
  • midbrain: 27 nTPM
  • hippocampal formation: 26 nTPM

Single-cell type

  • brain excitatory neurons: 281 nCPM
  • retinal horizontal cells: 281 nCPM
  • microglia: 244 nCPM
  • brain inhibitory neurons: 235 nCPM
  • other brain neurons: 234 nCPM
  • retinal ganglion cells: 216 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • pons: 114 nTPM
  • cerebral cortex: 110 nTPM
  • midbrain: 110 nTPM
  • basal ganglia: 103 nTPM
  • amygdala: 103 nTPM
  • hypothalamus: 97 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)
0.39
gnomAD pLI
0.54
gnomAD missense Z
2.23
DepMap mean gene effect
-0.03
DepMap dependency class
selective

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 APBA1 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 APBA1 as an antibody target. Whether an autoantibody or antibody against APBA1 could matter depends on whether native APBA1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

APBA1 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 APBA1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/APBA1. 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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