Seroatlas · Human Serome Atlas

H3-3A

Histone H3.3

Also known as: H3-3B, H3.3A, H3.3B, H33_HUMAN, H3F3, H3F3A, H3F3B

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

Protein identityUniProt · HPA

UniProt accession
P84243
Gene
H3-3A
Ensembl
ENSG00000163041
Chromosome
1
Canonical length
136 aa
Protein class
Cancer-related genes, Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Acrosome,Principal piece

OverviewNCBI Gene

Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Two molecules of each of the four core histones (H2A, H2B, H3, and H4) form an octamer, around which approximately 146 bp of DNA is wrapped in repeating units, called nucleosomes. The linker histone, H1, interacts with linker DNA between nucleosomes and functions in the compaction of chromatin into higher order structures. This gene contains introns and its mRNA is polyadenylated, unlike most histone genes. The protein encoded is a replication-independent member of the histone H3 family. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

136 residues, UniProt reviewed canonical sequence.

>P84243|H3-3A
     1  MARTKQTARK STGGKAPRKQ LATKAARKSA PSTGGVKKPH RYRPGTVALR EIRRYQKSTE
    61  LLIRKLPFQR LVREIAQDFK TDLRFQSAAI GALQEASEAY LVGLFEDTNL CAIHAKRVTI
   121  MPKDIQLARR IRGERA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against H3-3A 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)
0.53
Highest tissue expression
3,984 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 3,984 nTPM
  • skin: 1,069 nTPM
  • ovary: 981 nTPM
  • esophagus: 751 nTPM
  • cervix: 670 nTPM
  • vagina: 633 nTPM

Single-cell type

  • esophageal apical cells: 11,340 nCPM
  • esophageal suprabasal cells: 4,929 nCPM
  • neutrophils: 4,768 nCPM
  • early spermatids: 4,328 nCPM
  • syncytiotrophoblasts: 4,279 nCPM
  • mast cells: 3,616 nCPM

Immune cell

  • neutrophil: 21,236 nTPM
  • eosinophil: 10,095 nTPM
  • total PBMC: 9,631 nTPM
  • basophil: 8,031 nTPM
  • classical monocyte: 3,681 nTPM
  • intermediate monocyte: 3,374 nTPM

Brain region

  • white matter: 500 nTPM
  • cerebral cortex: 457 nTPM
  • medulla oblongata: 408 nTPM
  • cerebellum: 393 nTPM
  • basal ganglia: 382 nTPM
  • spinal cord: 373 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about H3-3A.

Disease | AllUniProt

Conditions H3-3A is implicated in, by any mechanism.

  • Glioma (GLM) MIM:137800
  • Bryant-Li-Bhoj neurodevelopmental syndrome 1 (BRYLIB1) MIM:619720
  • Bryant-Li-Bhoj neurodevelopmental syndrome 2 (BRYLIB2) MIM:619721

Disease | GeneticClinVar

20 pathogenic / likely-pathogenic of 62 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on H3-3A 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)
1.16
gnomAD pLI
0.12
DepMap mean gene effect
-1.29
DepMap dependency class
common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 9% 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 H3-3A 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 H3-3A as an antibody target. Whether an autoantibody or antibody against H3-3A could matter depends on whether native H3-3A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

H3-3A 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 H3-3A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/H3-3A. 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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