Reactome | Chromatin organization

Chromatin organization

Stable Identifier

R-HSA-4839726

Type

Pathway

Species

Homo sapiens

Compartment

nucleoplasm

ReviewStatus

5/5

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Chromatin organization (Homo sapiens)

General

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Eukaryotic DNA is associated with histone proteins and organized into a complex nucleoprotein structure called chromatin. This structure decreases the accessibility of DNA but also helps to protect it from damage (reviewed in Li and Reinberg, 2011; Gilbert et al, 2005; Desjarlais and Tummino, 2016).

The 'building block' of chromatin is the nucleosome. This contains ~150 bp of DNA wrapped around a histone octamer which consists of two each of the core histones H2A, H2B, H3 and H4 in a 1.65 left-handed superhelical turn (Luger et al. 1997; Andrews & Luger, 2011).

Most nucleosome assembly occurs in a coordinated fashion during DNA replication, with histone deposition occurring on newly synthesized DNA. Local changes in chromatin organization are required for transcription, DNA repair, regulation of gene expression and other processes. The accessibility of DNA is regulated by chromatin modifying enzymes that deposit post-translational epigenetic marks on histones and DNA and by ATP-dependent chromatin remodellers that use the energy of ATP to assemble, rearrange and reposition nucleosomes (reviewed in Desjarlais and Tummino, 2016; Allis and Jenuwein, 2016; Morgan and Shilatifard, 2020; Reyes et al, 2021).

Literature References

PubMed ID	Title	Journal	Year
33711345	Structure and Function of Chromatin Remodelers Reyes, AA, Marcum, RD, He, Y	J Mol Biol	2021
9305837	Crystal structure of the nucleosome core particle at 2.8 A resolution Luger, K, Mäder, AW, Richmond, RK, Sargent, DF, Richmond, TJ	Nature	1997
27346641	The molecular hallmarks of epigenetic control Allis, CD, Jenuwein, T	Nat Rev Genet	2016
26745824	Role of Histone-Modifying Enzymes and Their Complexes in Regulation of Chromatin Biology DesJarlais, R, Tummino, PJ	Biochemistry	2016
21332355	Nucleosome structure(s) and stability: variations on a theme Andrews, AJ, Luger, K	Annu Rev Biophys	2011
21342762	Chromatin higher-order structures and gene regulation Li, G, Reinberg, D	Curr. Opin. Genet. Dev.	2011
33257899	Reevaluating the roles of histone-modifying enzymes and their associated chromatin modifications in transcriptional regulation Morgan, MAJ, Shilatifard, A	Nat Genet	2020
15598472	Chromatin organization in the mammalian nucleus Gilbert, N, Gilchrist, S, Bickmore, WA	Int. Rev. Cytol.	2005