Structural highlights
Function
[H2AY_RAT] Variant histone H2A which replaces conventional H2A in a subset of nucleosomes where it represses transcription. 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. Involved in stable X chromosome inactivation. Inhibits the binding of transcription factors and interferes with the activity of remodeling SWI/SNF complexes. Inhibits histone acetylation by EP300 and recruits class I HDACs, which induces a hypoacetylated state of chromatin. In addition, isoform 1, but not isoform 2, binds ADP-ribose and O-acetyl-ADP-ribose, and may be involved in ADP-ribose-mediated chromatin modulation.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
macroH2A is an H2A variant with a highly unusual structural organization. It has a C-terminal domain connected to the N-terminal histone domain by a linker. Crystallographic and biochemical studies show that changes in the L1 loop in the histone fold region of macroH2A impact the structure and potentially the function of nucleosomes. The 1.6-A X-ray structure of the nonhistone region reveals an alpha/beta fold which has previously been found in a functionally diverse group of proteins. This region associates with histone deacetylases and affects the acetylation status of nucleosomes containing macroH2A. Thus, the unusual domain structure of macroH2A integrates independent functions that are instrumental in establishing a structurally and functionally unique chromatin domain.
Structural characterization of the histone variant macroH2A.,Chakravarthy S, Gundimella SK, Caron C, Perche PY, Pehrson JR, Khochbin S, Luger K Mol Cell Biol. 2005 Sep;25(17):7616-24. PMID:16107708[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Chakravarthy S, Gundimella SK, Caron C, Perche PY, Pehrson JR, Khochbin S, Luger K. Structural characterization of the histone variant macroH2A. Mol Cell Biol. 2005 Sep;25(17):7616-24. PMID:16107708 doi:http://dx.doi.org/25/17/7616
- ↑ Chakravarthy S, Gundimella SK, Caron C, Perche PY, Pehrson JR, Khochbin S, Luger K. Structural characterization of the histone variant macroH2A. Mol Cell Biol. 2005 Sep;25(17):7616-24. PMID:16107708 doi:http://dx.doi.org/25/17/7616
