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The SWI/SNF Subunit INI1 Contains an N-Terminal Winged Helix DNA Binding Domain that Is a Target for Mutations in Schwannomatosis.

ABSTRACT: SWI/SNF complexes use the energy of ATP hydrolysis to remodel chromatin. In mammals they play a central role in regulating gene expression during differentiation and proliferation. Mutations in SWI/SNF subunits are among the most frequent gene alterations in cancer. The INI1/hSNF5/SMARCB1 subunit is mutated in both malignant rhabdoid tumor, a highly aggressive childhood cancer, and schwannomatosis, a tumor-predisposing syndrome characterized by mostly benign tumors of the CNS. Here, we show that mutations in INI1 that cause schwannomatosis target a hitherto unidentified N-terminal winged helix DNA binding domain that is also present in the BAF45a/PHF10 subunit of the SWI/SNF complex. The domain is structurally related to the SKI/SNO/DAC domain, which is found in a number of metazoan chromatin-associated proteins.

SUBMITTER: Allen MD

PROVIDER: S-EPMC4509781 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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The SWI/SNF Subunit INI1 Contains an N-Terminal Winged Helix DNA Binding Domain that Is a Target for Mutations in Schwannomatosis.

Allen Mark D MD Freund Stefan M V SM Zinzalla Giovanna G Bycroft Mark M

Structure (London, England : 1993) 20150611 7

SWI/SNF complexes use the energy of ATP hydrolysis to remodel chromatin. In mammals they play a central role in regulating gene expression during differentiation and proliferation. Mutations in SWI/SNF subunits are among the most frequent gene alterations in cancer. The INI1/hSNF5/SMARCB1 subunit is mutated in both malignant rhabdoid tumor, a highly aggressive childhood cancer, and schwannomatosis, a tumor-predisposing syndrome characterized by mostly benign tumors of the CNS. Here, we show that ...[more]

PMID: 26073604

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