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Structural characterization of the histone variant macroH2A.

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.

SUBMITTER: Chakravarthy S

PROVIDER: S-EPMC1190287 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature

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Structural characterization of the histone variant macroH2A.

Chakravarthy Srinivas S Gundimella Sampath Kumar Y SK Caron Cecile C Perche Pierre-Yves PY Pehrson John R JR Khochbin Saadi S Luger Karolin K

Molecular and cellular biology 20050901 17

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 regi ...[more]

PMID: 16107708

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