Loss of the INI1 tumor suppressor does not impair the expression of multiple BRG1-dependent genes or the assembly of SWI/SNF enzymes
Authors
Doan, Diem N.Veal, Timothy M.
Yan, Zhijiang
Wang, Weidong
Jones, Stephen N.
Imbalzano, Anthony N.
UMass Chan Affiliations
Department of Cell BiologyDocument Type
Journal ArticlePublication Date
2004-03-03Keywords
AnimalsCell Line
Chromosomal Proteins, Non-Histone
DNA Helicases
DNA-Binding Proteins
*GTP-Binding Proteins
*Gene Expression Regulation
*Genes, Tumor Suppressor
Humans
Interferon-gamma
Nuclear Proteins
Proteins
Rabbits
Trans-Activators
Transcription Factors
Cell Biology
Metadata
Show full item recordAbstract
The INI1/hSNF5 tumor suppressor is an integral component of mammalian SWI/SNF chromatin remodeling enzymes that contain SNF2 family ATPases BRM (Brahma) or BRG1 (Brahma Related Gene 1) and that contribute to the regulation of many genes. Genetic studies of yeast SWI/SNF enzyme revealed similar phenotypes when single or multiple components of the enzyme were deleted, indicating a requirement for each subunit. To address the contribution of INI1 in the regulation of SWI/SNF-dependent genes in mammalian cells, we examined the expression of multiple BRG1-dependent, constitutively expressed genes in INI1-deficient cancer cell lines. At least one INI1-deficient line expressed each gene, and reintroduction of INI1 had negligible effects on expression levels. Lack of INI1 also did not prevent interferon gamma (IFNgamma)-mediated induction of CIITA, which is BRG1 dependent, and GBP-1, which is BRG1 enhanced, and reintroduction of INI1 had minimal effects. Chromatin immunoprecipitation experiments revealed that BRG1 inducibly binds to the CIITA promoter despite the absence of INI1. Unlike yeast deleted for the INI1 homologue, SWI/SNF enzymes in INI1-deficient cells were largely intact. Thus in human cells, SWI/SNF enzyme complex formation and the expression of many BRG1-dependent genes are independent of INI1.Source
Oncogene. 2004 Apr 22;23(19):3462-73. Link to article on publisher's siteDOI
10.1038/sj.onc.1207472Permanent Link to this Item
http://hdl.handle.net/20.500.14038/36021Related Resources
Link to Article in PubMedae974a485f413a2113503eed53cd6c53
10.1038/sj.onc.1207472
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