Seroatlas · Human Serome Atlas

A1CF

APOBEC1 complementation factor

Also known as: A1CF_HUMAN, ACF, ACF64, ACF65, APOBEC1CF, ASP

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

Protein identityUniProt · HPA

UniProt accession
Q9NQ94
Gene
A1CF
Ensembl
ENSG00000148584
Chromosome
10
Canonical length
594 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

Mammalian apolipoprotein B mRNA undergoes site-specific C to U deamination, which is mediated by a multi-component enzyme complex containing a minimal core composed of APOBEC-1 and a complementation factor encoded by this gene. The gene product has three non-identical RNA recognition motifs and belongs to the hnRNP R family of RNA-binding proteins. It has been proposed that this complementation factor functions as an RNA-binding subunit and docks APOBEC-1 to deaminate the upstream cytidine. Studies suggest that the protein may also be involved in other RNA editing or RNA processing events. Several transcript variants encoding a few different isoforms have been found for this gene. [provided by RefSeq, Nov 2010]

Canonical amino-acid sequenceUniProt

594 residues, UniProt reviewed canonical sequence.

>Q9NQ94|A1CF
     1  MESNHKSGDG LSGTQKEAAL RALVQRTGYS LVQENGQRKY GGPPPGWDAA PPERGCEIFI
    61  GKLPRDLFED ELIPLCEKIG KIYEMRMMMD FNGNNRGYAF VTFSNKVEAK NAIKQLNNYE
   121  IRNGRLLGVC ASVDNCRLFV GGIPKTKKRE EILSEMKKVT EGVVDVIVYP SAADKTKNRG
   181  FAFVEYESHR AAAMARRKLL PGRIQLWGHG IAVDWAEPEV EVDEDTMSSV KILYVRNLML
   241  STSEEMIEKE FNNIKPGAVE RVKKIRDYAF VHFSNREDAV EAMKALNGKV LDGSPIEVTL
   301  AKPVDKDSYV RYTRGTGGRG TMLQGEYTYS LGQVYDPTTT YLGAPVFYAP QTYAAIPSLH
   361  FPATKGHLSN RAIIRAPSVR EIYMNVPVGA AGVRGLGGRG YLAYTGLGRG YQVKGDKRED
   421  KLYDILPGME LTPMNPVTLK PQGIKLAPQI LEEICQKNNW GQPVYQLHSA IGQDQRQLFL
   481  YKITIPALAS QNPAIHPFTP PKLSAFVDEA KTYAAEYTLQ TLGIPTDGGD GTMATAAAAA
   541  TAFPGYAVPN ATAPVSAAQL KQAVTLGQDL AAYTTYEVYP TFAVTARGDG YGTF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against A1CF 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)
0.44
Highest tissue expression
143 nTPM

Expression across tissuesHPA

Tissue

  • liver: 143 nTPM
  • small intestine: 24 nTPM
  • duodenum: 21 nTPM
  • kidney: 12 nTPM
  • colon: 10 nTPM
  • rectum: 9.7 nTPM

Single-cell type

  • hepatocytes: 815 nCPM
  • neuroendocrine cells: 262 nCPM
  • enterocytes: 259 nCPM
  • cholangiocytes: 254 nCPM
  • pancreatic islet cells: 160 nCPM
  • colonocytes: 142 nCPM

Immune cell

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

Brain region

  • cerebral cortex: 0.7 nTPM
  • basal ganglia: 0.6 nTPM
  • cerebellum: 0.6 nTPM
  • white matter: 0.6 nTPM
  • amygdala: 0.5 nTPM
  • hippocampal formation: 0.5 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)
0.88
gnomAD pLI
0
gnomAD missense Z
0.99
DepMap mean gene effect
-0.08
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 A1CF 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 A1CF as an antibody target. Whether an autoantibody or antibody against A1CF could matter depends on whether native A1CF is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

A1CF 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 A1CF as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/A1CF. 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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