mTOR与Arid1A的互作对染色质重塑在代谢性调控中的功能与机制研究

Arid1A，one of famous gene in cancer biology for its high mutation rate, is a core subunit of SWI/SNF chromatin remodeling complex. Mutation of Arid1A or any other subunits of SWI/SNF correlated well with abnormal clear cell morphology in clinical cancer tissues which was major contribution from deregulated cellular carbohydrate metabolism. Consistently, there was indeed a cluster of genes involved in glucose and lipid cholesterol metabolism which may be co-regulated by Arid1A and mTOR signaling in our depth data analysis. So we proposed that much unknown regulation and mechanism lay behind the mTOR signaling and Arid1A involved chromatin remodeling complex. More interestingly, mTOR was one of original candidates of Arid1A interactome from our co-immunoprecipitation and mass spectrometry analysis. Based on the interaction of mTOR and Arid1A, this project will focus on study the interacting model between mTOR complex and Arid1A involved BAF complex, further investigate the regulation and mechanism from mTOR to Arid1A or from Arid1A to mTOR, then explore the related metabolic biofunction.

肿瘤细胞中高突变率的Arid1A是染色质重塑复合物SWI/SNF中的核心亚基，其特异性突变多伴随着异常的透明细胞形态特征，大多由碳水化合物代谢异常所致。通过数据挖掘，我们发现Arid1A参与调控了很多mTOR下游的糖脂胆固醇代谢基因群。揭示了mTOR和Arid1A参与的染色质重塑之间存在内在的关联和调控。我们以Arid1A为诱饵，利用免疫共沉淀和质谱鉴定分析，原创性地发现了Arid1A和mTOR之间的相互作用。本项目拟针对该相互作用，深度挖掘相互作用的模式，研究对应的调控关系和内在机制，并从代谢角度揭示背后的生物功能。

肿瘤细胞中高突变率的Arid1A是染色质重塑复合物SWI/SNF中的核心亚基，其特异性突变多伴随着异常的透明细胞形态特征，大多由碳水化合物代谢异常所致。通过数据挖掘，我们发现Arid1A参与调控了很多mTOR下游的糖脂胆固醇代谢基因群。揭示了mTOR和Arid1A参与的染色质重塑之间存在内在的关联和调控。我们以Arid1A为诱饵，利用免疫共沉淀和质谱鉴定分析，原创性地发现了Arid1A和mTOR之间的相互作用。本项目拟针对该相互作用，深度挖掘相互作用的模式，研究对应的调控关系和内在机制，并从代谢角度揭示背后的生物功能。本项目的研究内容包括（1）明确mTOR和Arid1A相互作用及作用模式；（2）探索mTOR和Arid1A之间的调控关系；（3）研究mTOR和Arid1A的调控机制；（4）研究mTOR和Arid1A之间调控的功能。我们的研究揭示，Arid1A和mTOR并无直接相互作用，但在功能上有着密切的联系，这是通过AMPK来介导的。Arid1A KO会引起AMPKalpha本底和磷酸化水平的上升，促进AMPK信号通路的活化，从而抑制mTOR信号通路。由于mTOR信号通路的钝化，Arid1A KO的肝癌细胞对外界营养剥夺具有更强的抗性。我们在DEN诱导的肝癌模型中发现，Arid1A KO通过激活AMPK，抑制mTOR，抑制了肝癌的发生发展。因此，本项目的研究揭示了Arid1A和mTOR的内在关联和调控机制，并且揭示了它们的crosstalk的生理意义。