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A role for BAF57 in cell cycle-dependent transcriptional regulation by the SWI/SNF chromatin remodeling complex.

ABSTRACT: The SWI/SNF complex is an ATP-dependent chromatin remodeling complex that plays pivotal roles in gene regulation and cell cycle control. In the present study, we explored the molecular functions of the BAF57 subunit of SWI/SNF in cell cycle control via transcriptional regulation of cell cycle-related genes. We affinity purified SWI/SNF from HeLa cells stably expressing FLAG-tagged BAF47/Ini1 with or without stable short hairpin RNA-mediated knockdown of BAF57. The subunit composition of the holo-SWI/SNF and BAF57-depleted SWI/SNF complexes from these cells was determined using a quantitative SILAC (stable isotope labeling by amino acids in cell culture)-based proteomic approach. Depletion of BAF57 resulted in a significant codepletion of BAF180 from the SWI/SNF complex without decreasing total cellular BAF180 levels. In biochemical assays of SWI/SNF activity, the holo-SWI/SNF and BAF57/BAF180-depleted SWI/SNF complexes exhibited similar activities. However, in cell proliferation assays using HeLa cells, knockdown of BAF57 resulted in an accumulation of cells in the G(2)-M phase, inhibition of colony formation, and impaired growth in soft agar. Knockdown of BAF57 also caused transcriptional misregulation of various cell cycle-related genes, especially genes involved in late G(2). Collectively, our results have identified a new role for BAF57 within the SWI/SNF complex that is required for (a) maintaining the proper subunit composition of the complex and (b) cell cycle progression through the transcriptional regulation of a subset of cell cycle-related genes.

SUBMITTER: Hah N

PROVIDER: S-EPMC2880201 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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A role for BAF57 in cell cycle-dependent transcriptional regulation by the SWI/SNF chromatin remodeling complex.

Hah Nasun N Kolkman Annemieke A Ruhl Donald D DD Pijnappel W W M Pim WW Heck Albert J R AJ Timmers H Th Marc HT Kraus W Lee WL

Cancer research 20100511 11

The SWI/SNF complex is an ATP-dependent chromatin remodeling complex that plays pivotal roles in gene regulation and cell cycle control. In the present study, we explored the molecular functions of the BAF57 subunit of SWI/SNF in cell cycle control via transcriptional regulation of cell cycle-related genes. We affinity purified SWI/SNF from HeLa cells stably expressing FLAG-tagged BAF47/Ini1 with or without stable short hairpin RNA-mediated knockdown of BAF57. The subunit composition of the holo ...[more]

PMID: 20460533

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Dataset Information

A role for BAF57 in cell cycle-dependent transcriptional regulation by the SWI/SNF chromatin remodeling complex.

Publications

A role for BAF57 in cell cycle-dependent transcriptional regulation by the SWI/SNF chromatin remodeling complex.

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