Seroatlas · Human Serome Atlas

AICDA

Single-stranded DNA cytosine deaminase

Also known as: AICDA_HUMAN, AID, ARP2, CDA2, HIGM2

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

Protein identityUniProt · HPA

UniProt accession
Q9GZX7
Gene
AICDA
Ensembl
ENSG00000111732
Chromosome
12
Canonical length
198 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins

OverviewNCBI Gene

This gene encodes a RNA-editing deaminase that is a member of the cytidine deaminase family. AICDA is specifically expressed and active in germinal center-like B cells. In the germinal center, AICDA is involved in somatic hypermutation, gene conversion, and class-switch recombination of immunoglobulin genes. An epigenetic role in neoplastic transformation and lymphoma progression has been experimentally ascribed to AICDA using mouse models. Defects in this gene are the cause of autosomal recessive hyper-IgM immunodeficiency syndrome type 2 (HIGM2). [provided by RefSeq, Jul 2020]

Canonical amino-acid sequenceUniProt

198 residues, UniProt reviewed canonical sequence.

>Q9GZX7|AICDA
     1  MDSLLMNRRK FLYQFKNVRW AKGRRETYLC YVVKRRDSAT SFSLDFGYLR NKNGCHVELL
    61  FLRYISDWDL DPGRCYRVTW FTSWSPCYDC ARHVADFLRG NPNLSLRIFT ARLYFCEDRK
   121  AEPEGLRRLH RAGVQIAIMT FKDYFYCWNT FVENHERTFK AWEGLHENSV RLSRQLRRIL
   181  LPLYEVDDLR DAFRTLGL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AICDA 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)
0.31
Highest tissue expression
11 nTPM

Expression across tissuesHPA

Tissue

  • lymph node: 11 nTPM
  • tonsil: 8.8 nTPM
  • appendix: 2.9 nTPM
  • skeletal muscle: 1.5 nTPM
  • small intestine: 0.7 nTPM
  • gallbladder: 0.4 nTPM

Single-cell type

  • paneth cells: 3.9 nCPM
  • fibro-adipogenic progenitors: 2.5 nCPM
  • enterocytes: 2.2 nCPM
  • b-cells: 1.8 nCPM
  • undifferentiated spermatogonia: 0.9 nCPM
  • fibroblasts: 0.7 nCPM

Immune cell

  • naive B-cell: 2.1 nTPM
  • memory B-cell: 1.3 nTPM
  • neutrophil: 0.5 nTPM
  • basophil: 0.4 nTPM
  • classical monocyte: 0.2 nTPM
  • plasmacytoid DC: 0.2 nTPM

Brain region

  • cerebral cortex: 1.4 nTPM
  • white matter: 1.3 nTPM
  • midbrain: 1.2 nTPM
  • cerebellum: 0.9 nTPM
  • pons: 0.8 nTPM
  • thalamus: 0.8 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about AICDA.

Disease | AllUniProt

Conditions AICDA is implicated in, by any mechanism.

  • Immunodeficiency with hyper-IgM 2 (HIGM2) MIM:605258

Disease | GeneticClinVar

36 pathogenic / likely-pathogenic of 296 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Hyper-IgM syndrome type 2
  • AICDA-related disorder

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)
1.33
gnomAD pLI
0
gnomAD missense Z
1.34
DepMap mean gene effect
0.06
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 2% 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 AICDA 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 AICDA as an antibody target. Whether an autoantibody or antibody against AICDA could matter depends on whether native AICDA is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

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

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