Seroatlas · Human Serome Atlas

H2AC21

Histone H2A type 2-B

Also known as: H2A2B_HUMAN, HIST2H2AB

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

Protein identityUniProt · HPA

UniProt accession
Q8IUE6
Gene
H2AC21
Ensembl
ENSG00000184270
Chromosome
1
Canonical length
130 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Nucleosomes consist of approximately 146 bp of DNA wrapped around a histone octamer composed of pairs of each of the four core histones (H2A, H2B, H3, and H4). The chromatin fiber is further compacted through the interaction of a linker histone, H1, with the DNA between the nucleosomes to form higher order chromatin structures. This gene is intronless and encodes a replication-dependent histone that is a member of the histone H2A family. Transcripts from this gene contain a palindromic termination element. [provided by RefSeq, Aug 2015]

Canonical amino-acid sequenceUniProt

130 residues, UniProt reviewed canonical sequence.

>Q8IUE6|H2AC21
     1  MSGRGKQGGK ARAKAKSRSS RAGLQFPVGR VHRLLRKGNY AERVGAGAPV YLAAVLEYLT
    61  AEILELAGNA ARDNKKTRII PRHLQLAVRN DEELNKLLGG VTIAQGGVLP NIQAVLLPKK
   121  TESHKPGKNK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against H2AC21 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)
0.49
Highest tissue expression
3.2 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 3.2 nTPM
  • choroid plexus: 0.6 nTPM
  • skin: 0.6 nTPM
  • small intestine: 0.5 nTPM
  • spleen: 0.4 nTPM
  • breast: 0.3 nTPM

Single-cell type

  • erythrocyte progenitors: 47 nCPM
  • megakaryocyte progenitors: 34 nCPM
  • monocyte progenitors: 34 nCPM
  • tuft cells: 12 nCPM
  • mucous neck cells: 11 nCPM
  • neutrophil progenitors: 7.5 nCPM

Immune cell

  • neutrophil: 9.9 nTPM
  • naive B-cell: 6.6 nTPM
  • plasmacytoid DC: 4 nTPM
  • memory B-cell: 3.7 nTPM
  • memory CD4 T-cell: 3.7 nTPM
  • NK-cell: 3.6 nTPM

Brain region

  • cerebellum: 63 nTPM
  • basal ganglia: 40 nTPM
  • white matter: 38 nTPM
  • hypothalamus: 37 nTPM
  • cerebral cortex: 36 nTPM
  • amygdala: 36 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about H2AC21.

Disease | ImmuneIEDB

Conditions an epitope on H2AC21 was assayed in.

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)
0.98
gnomAD pLI
0.61
DepMap mean gene effect
-0.32
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 H2AC21 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 H2AC21 as an antibody target. Whether an autoantibody or antibody against H2AC21 could matter depends on whether native H2AC21 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

H2AC21 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 H2AC21 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/H2AC21. 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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