期刊
FEBS JOURNAL
卷 277, 期 6, 页码 1453-1464出版社
WILEY
DOI: 10.1111/j.1742-4658.2010.07575.x
关键词
BAF60; Rac GTPase; RING finger; SWI/SNF complex; ubiquitination
资金
- INSERM
- CNRS
- Universite Paris Descartes
- Agence Nationale pour la Recherche [ANR 05-MRAR-033-02]
- Association pour la recherche sur le cancer
The SWI/SNF chromatin remodelling complexes are important regulators of transcription; they consist of large multisubunit assemblies containing either Brm or Brg1 as the catalytic ATPase subunit and a variable subset of approximately 10 Brg/Brm-associated factors (BAF). Among these factors, BAF60 proteins (BAF60a, BAF60b or BAF60c), which are found in most complexes, are thought to bridge interactions between transcription factors and SWI/SNF complexes. We report here on a Rac-dependent process leading to BAF60b ubiquitination. Using two-hybrid cloning procedures, we identified a mammalian RING finger protein homologous to drosophila Unkempt as a new partner of the activated form of RacGTPases and demonstrated that mammalian Unkempt specifically binds to BAF60b and promotes its ubiquitination in a Rac1-dependent manner. Immunofluorescence studies demonstrated that Unkempt is primarily localized in the cytoplasmic compartment, but has the ability to shuttle between the nucleus and the cytoplasm, suggesting that the Rac- and Unkempt-dependent process leading to BAF60b ubiquitination takes place in the nuclear compartment. Ubiquitinated forms of BAF60b were found to accumulate upon treatment with the proteasome inhibitor MG132, indicating that BAF60b ubiquitination is of the degradative type and could regulate the level of BAF60b in SWI/SNF complexes. Our observations support the new idea of a direct connection between Rac signalling and chromatin remodelling.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据