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Details on Person UniProt:Q16777 H2AC20

Class:IdReferenceGeneProduct:56148
_chainChangeLoginitiator methionine:1 added on Fri February 6 2015;chain:2-129 added on Fri February 6 2015;initiator methionine:1 for 56148 removed on Fri Nov 03 2023;initiator methionine: for 56148 added on Fri Nov 03 2023;initiator methionine: for 56148 removed on Fri Aug 15 2025;initiator methionine:1 for 56148 added on Fri Aug 15 2025
_displayNameUniProt:Q16777 H2AC20
_timestamp2026-02-20 21:40:10
chaininitiator methionine:1
chain:2-129
checksum358AE20D1C531724
commentFUNCTION Core component of nucleosome. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling.SUBUNIT The nucleosome is a histone octamer containing two molecules each of H2A, H2B, H3 and H4 assembled in one H3-H4 heterotetramer and two H2A-H2B heterodimers. The octamer wraps approximately 147 bp of DNA.SUBCELLULAR LOCATION Deiminated on Arg-4 in granulocytes upon calcium entry.PTM Monoubiquitination of Lys-120 (H2AK119Ub) by RING1, TRIM37 and RNF2/RING2 complex gives a specific tag for epigenetic transcriptional repression and participates in X chromosome inactivation of female mammals. It is involved in the initiation of both imprinted and random X inactivation. Ubiquitinated H2A is enriched in inactive X chromosome chromatin. Ubiquitination of H2A functions downstream of methylation of 'Lys-27' of histone H3 (H3K27me). H2AK119Ub by RNF2/RING2 can also be induced by ultraviolet and may be involved in DNA repair. Monoubiquitination of Lys-120 (H2AK119Ub) by TRIM37 may promote transformation of cells in a number of breast cancers (PubMed:25470042). Following DNA double-strand breaks (DSBs), it is ubiquitinated through 'Lys-63' linkage of ubiquitin moieties by the E2 ligase UBE2N and the E3 ligases RNF8 and RNF168, leading to the recruitment of repair proteins to sites of DNA damage. Ubiquitination at Lys-14 and Lys-16 (H2AK13Ub and H2AK15Ub, respectively) in response to DNA damage is initiated by RNF168 that mediates monoubiquitination at these 2 sites, and 'Lys-63'-linked ubiquitin are then conjugated to monoubiquitin; RNF8 is able to extend 'Lys-63'-linked ubiquitin chains in vitro. Deubiquitinated by USP51 at Lys-14 and Lys-16 (H2AK13Ub and H2AK15Ub, respectively) after damaged DNA is repaired (PubMed:27083998). H2AK119Ub and ionizing radiation-induced 'Lys-63'-linked ubiquitination (H2AK13Ub and H2AK15Ub) are distinct events.PTM Phosphorylation on Ser-2 (H2AS1ph) is enhanced during mitosis. Phosphorylation on Ser-2 by RPS6KA5/MSK1 directly represses transcription. Acetylation of H3 inhibits Ser-2 phosphorylation by RPS6KA5/MSK1. Phosphorylation at Thr-121 (H2AT120ph) by DCAF1 is present in the regulatory region of many tumor suppresor genes and down-regulates their transcription.PTM Symmetric dimethylation on Arg-4 by the PRDM1/PRMT5 complex may play a crucial role in the germ-cell lineage.PTM Glutamine methylation at Gln-105 (H2AQ104me) by FBL is specifically dedicated to polymerase I. It is present at 35S ribosomal DNA locus and impairs binding of the FACT complex (PubMed:24352239).PTM Crotonylation (Kcr) is specifically present in male germ cells and marks testis-specific genes in post-meiotic cells, including X-linked genes that escape sex chromosome inactivation in haploid cells. Crotonylation marks active promoters and enhancers and confers resistance to transcriptional repressors. It is also associated with post-meiotically activated genes on autosomes.PTM Lactylated in macrophages by EP300/P300 by using lactoyl-CoA directly derived from endogenous or exogenous lactate, leading to stimulates gene transcription.MASS SPECTROMETRY Monoisotopic with N-acetylserine.SIMILARITY Belongs to the histone H2A family.
descriptionrecommendedName: Histone H2A type 2-C alternativeName: fullName evidence="33"H2A-clustered histone 20 alternativeName: Histone H2A-GL101 alternativeName: Histone H2A/q
geneNameH2AC20
H2AFQ
HIST2H2AC
identifierQ16777
isSequenceChangedFALSE
keyword3D-structure
Acetylation
Chromosome
Citrullination
DNA-binding
Hydroxylation
Isopeptide bond
Methylation
Nucleosome core
Nucleus
Phosphoprotein
Proteomics identification
Reference proteome
Ubl conjugation
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9963647] Weiser, Joel, 2025-08-15
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameH2AC20
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8958118] ENSEMBL:ENSG00000184260 H2AC20 [Homo sapiens]
secondaryIdentifierH2A2C_HUMAN
Q6DRA7
Q8IUE5
sequenceLength129
species[Species:48887] Homo sapiens
(referenceEntity)[EntityWithAccessionedSequence:181892] HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:977563] HIST2H2AC [extracellular region] [Homo sapiens]
[EntityWithAccessionedSequence:4551338] AcK-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:4568572] AcK6-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:5218305] Me2sR4-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:5229227] MeR12-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:5229306] Me2aR12-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:5244542] MeR30-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:5244562] Me2aR30-HIST2H2AC [nucleoplasm] [Homo sapiens]
[EntityWithAccessionedSequence:5244589] Me2aR4-HIST2H2AC [nucleoplasm] [Homo sapiens]
List all 13 refering instances
(referenceSequence)[ModifiedResidue:4551315] N6-acetyl-L-lysine at unknown position
[ModifiedResidue:4568586] N6-acetyl-L-lysine at 6
[ModifiedResidue:5218309] symmetric dimethyl-L-arginine at 4
[ModifiedResidue:5229204] omega-N-methyl-L-arginine at 12
[ModifiedResidue:5229309] asymmetric dimethyl-L-arginine at 12
[ModifiedResidue:5244537] omega-N-methyl-L-arginine at 30
[ModifiedResidue:5244556] asymmetric dimethyl-L-arginine at 30
[ModifiedResidue:5244592] asymmetric dimethyl-L-arginine at 4
[ModifiedResidue:5244614] omega-N-methyl-L-arginine at 4
[GroupModifiedResidue:6782519] ubiquitinylated lysine (monoUb [nucleoplasm]) at 120
List all 11 refering instances
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No pathways have been reviewed or authored by UniProt:Q16777 H2AC20 (56148)