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The histone chaperones Vps75 and Nap1 form ring-like, tetrameric structures in solution.

ABSTRACT: NAP-1 fold histone chaperones play an important role in escorting histones to and from sites of nucleosome assembly and disassembly. The two NAP-1 fold histone chaperones in budding yeast, Vps75 and Nap1, have previously been crystalized in a characteristic homodimeric conformation. In this study, a combination of small angle X-ray scattering, multi angle light scattering and pulsed electron-electron double resonance approaches were used to show that both Vps75 and Nap1 adopt ring-shaped tetrameric conformations in solution. This suggests that the formation of homotetramers is a common feature of NAP-1 fold histone chaperones. The tetramerisation of NAP-1 fold histone chaperones may act to shield acidic surfaces in the absence of histone cargo thus providing a 'self-chaperoning' type mechanism.

SUBMITTER: Bowman A

PROVIDER: S-EPMC4027167 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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The histone chaperones Vps75 and Nap1 form ring-like, tetrameric structures in solution.

Bowman Andrew A Hammond Colin M CM Stirling Andrew A Ward Richard R Shang Weifeng W El-Mkami Hassane H Robinson David A DA Svergun Dmitri I DI Norman David G DG Owen-Hughes Tom T

Nucleic acids research 20140331 9

NAP-1 fold histone chaperones play an important role in escorting histones to and from sites of nucleosome assembly and disassembly. The two NAP-1 fold histone chaperones in budding yeast, Vps75 and Nap1, have previously been crystalized in a characteristic homodimeric conformation. In this study, a combination of small angle X-ray scattering, multi angle light scattering and pulsed electron-electron double resonance approaches were used to show that both Vps75 and Nap1 adopt ring-shaped tetrame ...[more]

PMID: 24688059

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