Seroatlas · Human Serome Atlas

APBB1

Amyloid beta precursor protein binding family B member 1

Also known as: APBB1_HUMAN, Fe65, RIR

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

Protein identityUniProt · HPA

UniProt accession
O00213
Gene
APBB1
Ensembl
ENSG00000166313
Chromosome
11
Canonical length
710 aa
Protein class
Plasma proteins, Predicted intracellular proteins
Subcellular location
Plasma membrane

OverviewNCBI Gene

The protein encoded by this gene is a member of the Fe65 protein family. It is an adaptor protein localized in the nucleus. It interacts with the Alzheimer's disease amyloid precursor protein (APP), transcription factor CP2/LSF/LBP1 and the low-density lipoprotein receptor-related protein. APP functions as a cytosolic anchoring site that can prevent the gene product's nuclear translocation. This encoded protein could play an important role in the pathogenesis of Alzheimer's disease. It is thought to regulate transcription. Also it is observed to block cell cycle progression by downregulating thymidylate synthase expression. Multiple alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Mar 2012]

Canonical amino-acid sequenceUniProt

710 residues, UniProt reviewed canonical sequence.

>O00213|APBB1
     1  MSVPSSLSQS AINANSHGGP ALSLPLPLHA AHNQLLNAKL QATAVGPKDL RSAMGEGGGP
    61  EPGPANAKWL KEGQNQLRRA ATAHRDQNRN VTLTLAEEAS QEPEMAPLGP KGLIHLYSEL
   121  ELSAHNAANR GLRGPGLIIS TQEQGPDEGE EKAAGEAEEE EEDDDDEEEE EDLSSPPGLP
   181  EPLESVEAPP RPQALTDGPR EHSKSASLLF GMRNSAASDE DSSWATLSQG SPSYGSPEDT
   241  DSFWNPNAFE TDSDLPAGWM RVQDTSGTYY WHIPTGTTQW EPPGRASPSQ GSSPQEESQL
   301  TWTGFAHGEG FEDGEFWKDE PSDEAPMELG LKEPEEGTLT FPAQSLSPEP LPQEEEKLPP
   361  RNTNPGIKCF AVRSLGWVEM TEEELAPGRS SVAVNNCIRQ LSYHKNNLHD PMSGGWGEGK
   421  DLLLQLEDET LKLVEPQSQA LLHAQPIISI RVWGVGRDSG RERDFAYVAR DKLTQMLKCH
   481  VFRCEAPAKN IATSLHEICS KIMAERRNAR CLVNGLSLDH SKLVDVPFQV EFPAPKNELV
   541  QKFQVYYLGN VPVAKPVGVD VINGALESVL SSSSREQWTP SHVSVAPATL TILHQQTEAV
   601  LGECRVRFLS FLAVGRDVHT FAFIMAAGPA SFCCHMFWCE PNAASLSEAV QAACMLRYQK
   661  CLDARSQAST SCLPAPPAES VARRVGWTVR RGVQSLWGSL KPKRLGAHTP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against APBB1 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)
0.54
Highest tissue expression
192 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 192 nTPM
  • cerebral cortex: 158 nTPM
  • spinal cord: 134 nTPM
  • hippocampal formation: 99 nTPM
  • amygdala: 92 nTPM
  • midbrain: 90 nTPM

Single-cell type

  • oligodendrocytes: 152 nCPM
  • brain excitatory neurons: 76 nCPM
  • oligodendrocyte progenitor cells: 74 nCPM
  • retinal bipolar cells: 69 nCPM
  • pancreatic islet cells: 62 nCPM
  • brain inhibitory neurons: 58 nCPM

Immune cell

  • naive CD4 T-cell: 86 nTPM
  • naive CD8 T-cell: 52 nTPM
  • T-reg: 49 nTPM
  • memory CD4 T-cell: 33 nTPM
  • memory CD8 T-cell: 30 nTPM
  • total PBMC: 30 nTPM

Brain region

  • white matter: 265 nTPM
  • pons: 241 nTPM
  • cerebral cortex: 212 nTPM
  • cerebellum: 202 nTPM
  • basal ganglia: 202 nTPM
  • medulla oblongata: 194 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)
0.32
gnomAD pLI
0.97
gnomAD missense Z
1.56
DepMap mean gene effect
-0.01
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

InteractionsUniProt · HPA

Protein binding partners of APBB1 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 APBB1 as an antibody target. Whether an autoantibody or antibody against APBB1 could matter depends on whether native APBB1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

APBB1 is annotated at the cell surface, where native APBB1 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 APBB1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/APBB1. 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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