Regulatory Precision in Stress Responsive Transcriptional Networks

项目摘要 许多细胞挑战-化学，代谢和物理-产生活性氧（ROS）， 其具有破坏包括蛋白质、脂质和核酸的大分子的潜力。成员 包括NRF 2在内帽-领（CNC）转录因子家族调节抗氧化剂基因表达， 减轻ROS介导的损伤。这些相反的氧化剂和抗氧化剂力量必须精确平衡： 太少的NRF 2和过量的ROS会导致细胞损伤和突变，而太多的NRF 2则会使细胞发生凋亡。 危险的增殖优势为了充分理解NRF 2激活的机制，我们 需要对其监管网络有一个全面的了解，但令人惊讶的是， NRF 2的调节活性以及它如何与其他应激反应转录因子整合。我们将 使用假设驱动的基因组学和集中的生物验证实验的组合， 对NRF 2调控网络及其后果的系统水平和机械见解 activation.重要的是，这项工作还将解决有关转录的一般原则的问题， 调控的精确性，包括：（1）如何转录因子DNA结合特性和组合 转录因子相互作用整合以驱动分级与开关样基因表达，（2）动态 和人类细胞中快速转录重编程的细胞类型特异性，（3）顺式- 调节DNA在功能上与疾病风险相关，以及（4）细胞自主和非自主的机制。 自治调节网络传播。这些都是与所有转录调控因子相关的问题，因此， 在NRF 2介导的基因调控背景下获得的知识也将扩展到额外的转录 因素家庭。

PROJECT SUMMARY Many cellular challenges – chemical, metabolic, and physical – generate reactive oxygen species (ROS), which have the potential to damage macromolecules including proteins, lipids, and nucleic acids. Members of the Cap-n-Collar (CNC) transcription factor family, including NRF2, regulate antioxidant gene expression and mitigate ROS-mediated damage. These opposing oxidant and antioxidant forces must be precisely balanced: too little NRF2 and excess ROS cause cell damage and mutation, whereas too much NRF2 gives cells a dangerous proliferative advantage. To fully understand the mechanistic implications of NRF2 activation we need a comprehensive view of its regulatory network, yet surprisingly little is known about the global reach of NRF2's regulatory activity and how it integrates with additional stress-responsive transcription factors. We will use a combination of hypothesis-driven genomics and focused biological validation experiments to provide both systems level and mechanistic insights into the NRF2 regulatory network and consequences of its activation. Importantly, this work will also address issues regarding the general principles of transcriptional regulatory precision, including: (1) how transcription factor DNA binding properties and combinatorial transcription factor interactions integrate to drive graded versus switch-like gene expression, (2) the dynamics and cell-type specificity of rapid transcriptional reprogramming in human cells, (3) how variation in cis- regulatory DNA is functionally linked to disease risk, and (4) the mechanisms of cell autonomous and non- autonomous regulatory network propagation. These are relevant issues for all transcriptional regulators, so the knowledge gained in the context of NRF2-mediated gene regulation will also extend to additional transcription factor families.