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Structural analysis of Rtt106p reveals a DNA binding role required for heterochromatin silencing.

ABSTRACT: Rtt106p is a Saccharomyces cerevisiae histone chaperone with roles in heterochromatin silencing and nucleosome assembly. The molecular mechanism by which Rtt106p engages in chromatin dynamics remains unclear. Here, we report the 2.5 A crystal structure of the core domain of Rtt106p, which adopts an unusual "double pleckstrin homology" domain architecture that represents a novel structural mode for histone chaperones. A histone H3-H4-binding region and a novel double-stranded DNA-binding region have been identified. Mutagenesis studies reveal that the histone and DNA binding activities of Rtt106p are involved in Sir protein-mediated heterochromatin formation. Our results uncover the structural basis of the diverse functions of Rtt106p and provide new insights into its cellular roles.

SUBMITTER: Liu Y

PROVIDER: S-EPMC2824209 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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Structural analysis of Rtt106p reveals a DNA binding role required for heterochromatin silencing.

Liu Yiwei Y Huang Hongda H Zhou Bo O BO Wang Shan-Shan SS Hu Yingxia Y Li Xu X Liu Jianping J Zang Jianye J Niu Liwen L Wu Jihui J Zhou Jin-Qiu JQ Teng Maikun M Shi Yunyu Y

The Journal of biological chemistry 20091210 6

Rtt106p is a Saccharomyces cerevisiae histone chaperone with roles in heterochromatin silencing and nucleosome assembly. The molecular mechanism by which Rtt106p engages in chromatin dynamics remains unclear. Here, we report the 2.5 A crystal structure of the core domain of Rtt106p, which adopts an unusual "double pleckstrin homology" domain architecture that represents a novel structural mode for histone chaperones. A histone H3-H4-binding region and a novel double-stranded DNA-binding region h ...[more]

PMID: 20007951

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