Function and Regulation of the CSN in the NF-kB Activation Pathway

描述(申请人提供)：COP9信号体(CSN)复合体是一种进化上保守的蛋白质复合体，存在于所有真核生物中，参与控制不同的细胞和发育过程。CSN复合体的失调可以对肿瘤发展至关重要的细胞功能产生巨大影响，包括维持DNA保真度、细胞周期控制、DNA修复、血管生成和微环境动态平衡。最近发现CSN复合体参与了由卓越信号激活的核因子-βB的调节。但对CSN复合体在信号诱导的核因子-β活化途径中的作用和调控缺乏充分的了解。核因子？B蛋白是一种可诱导的转录因子，在许多生理和病理生理过程中起着至关重要的调节作用。核因子-β的异常调控和控制其活性的信号通路(如TNFa通路)参与了肿瘤的发生、发展以及对化疗和放疗的抵抗。因此，核因子-β及其活性调节成分已成为药物发现的焦点。鉴于其在癌症发展中的重要作用，我们假设，对核因子-βB途径中的CSN复合体的详细分析不仅将为其功能和调控提供新的见解，而且将为未来通过CSN复合体针对核因子-βB系统的癌症治疗提供新的方向。为了测试这一点，我们建议实现以下特定目标：1)确定与TNFa信号触发的NF-β激活相关的人CSN复合体的蛋白质相互作用动力学。2)研究CSN5的磷酸化以及CSN5-IKK复合体与TNFa信号的动态相互作用。这项拟议的工作代表了首次在信号通路的背景下对CSN复合体进行详细的蛋白质组学分析。这项工作开发的方法学将适用于其他响应细胞外信号的蛋白质复合体的研究。

DESCRIPTION (provided by applicant): The COP9 signalosome (CSN) complex is an evolutionally conserved protein complex present in all eukaryotes and is involved in controlling diverse cellular and developmental processes. Disregulation of the CSN complex can have a dramatic effect on cellular functions critical to tumor development, including maintenance of DNA fidelity, cell cycle control, DNA repair, angiogenesis, and micro-environmental homeostasis. The CSN complex has recently been found to be involved in the regulation of NF-?B activated by excellular signaling. But a full understanding of the function and regulation of the CSN complex in signal-induced NF-?B activation pathways is lacking. NF-?B proteins are inducible transcription factors that are crucial regulators of many physiological and pathophysiological processes. Aberrant regulation of NF-?B and the signaling pathways (e.g. TNFa pathway) controlling its activity are involved in cancer development and progression, as well as resistance to chemotherapy and radiotherapy. Therefore, NF-?B and components involved in regulating its activity have become a focal point for drug discovery. Given its critica importance in cancer development, we hypothesize that detailed analysis of the CSN complex in the NF-?B pathway will not only provide new insights into its function and regulation in general, but also lead to new directions in future development of clinically useful inhibitors for cancer treatment targeting the NF-?B system through the CSN complex. To test this, we propose to achieve the following specific aims: 1) To define protein interaction dynamics of the human CSN complex associated with NF-?B activation triggered by TNFa signaling. 2) To characterize CSN5 phosphorylation and the dynamic interactions of the CSN5-IKK complex upon TNFa signaling. The proposed work represents the first detailed proteomic analysis of the CSN complex in the context of signaling pathways. The methodology developed in this work will be applicable for the study of other protein complexes in response to extracellular signaling.