Structural characterization of the histone variant macroH2A.

Srinivas Chakravarthy; Sampath Kumar Y Gundimella; Cecile Caron; Pierre-Yves Perche; John R Pehrson; Saadi Khochbin; Karolin Luger

doi:10.1128/mcb.25.17.7616-7624.2005

PubMed · 16107708

Structural characterization of the histone variant macroH2A.

Srinivas Chakravarthy·Sampath Kumar Y Gundimella·Cecile Caron·Pierre-Yves Perche·John R Pehrson·Saadi Khochbin·Karolin Luger

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Abstract

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.

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Acetylation Amino Acid Sequence Animals Cell Line Chlorocebus aethiops Chromatin Crystallography, X-Ray Histones Humans Mice Models, Molecular Molecular Sequence Data Protein Structure, Tertiary Sequence Alignment Xenopus laevis Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Srinivas Chakravarthy, Sampath Kumar Y Gundimella, Cecile Caron, Pierre-Yves Perche, John R Pehrson, Saadi Khochbin, Karolin Luger. 2005. Structural characterization of the histone variant macroH2A.. https://doi.org/10.1128/mcb.25.17.7616-7624.2005

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