Examining the Intersection of Transitional Metals and Kinase Signal Transduction Networks

项目总结/摘要 正常的生理学依赖于细胞内信号形式的内在线索的精确协调 转导途径，与外部线索，如营养的可用性，以平衡细胞生长和细胞死亡。 过渡金属，如铜（Cu）是严格管制的微量营养素，其功能是结构或催化 蛋白质的辅助因子对正常生理和发育至关重要。铜排泄异常， 吸收分别表现在极其罕见的遗传病威尔逊和门克斯。的 发育迟缓的生长强调了完整的铜稳态机制对细胞生长控制的重要性 与门克斯病患者中铜缺乏相关的生长障碍和癌症的患病率， Wilson病中遗传性铜超载的患者。此外，铜既不是创造的，也不是毁灭的， 因此，低铜饮食摄入可能是伤口愈合受损，心血管疾病， 和非酒精性脂肪肝。然而，目前确定的少数铜- 依赖酶不能完全解释与铜改变相关的不同生长表型 新陈代谢.因此，响应和/或感测Cu丰度并整合的直接细胞途径 影响细胞增殖的机制尚未明确。我们小组最近的工作发现了一个意想不到的联系 细胞获得铜和促有丝分裂信号级联之间的联系。为了响应增殖信号， Cu通过Cu与MAPK信号传导通路的直接相互作用而对经典MAPK信号传导的幅度有贡献。 激酶MEK 1和MEK 2。这是铜直接调节哺乳动物激酶活性的第一个例子 并揭示了一种新的信号模式，直接连接铜信号通路组件。基于 在我们的专业知识，我们的小组试图确定铜响应和传感激酶信号转导 途径，以确定铜有助于促增殖细胞过程的机制， 对于正常增殖是必需的，并且在肿瘤发生期间持续存在。为了实现我们的目标，我们将 利用多学科方法，包括体内小鼠模型，生物化学，生物物理学，分子生物学， 生物学、功能基因组学和药理学干预。具体而言，我们将：i）阐明 分子机制和细胞环境的基础铜整合到MAPK途径，ii） 通过促增殖激酶信号转导途径系统地绘制Cu利用，和iii） 将我们的实验方法和发现用于其他过渡金属和激酶信号传导 正常稳态和癌症中的网络。完成这些研究有可能建立铜 作为细胞内通讯的一个组成部分，并阐明分子机制 这种独特的联系。此外，鉴定新的Cu依赖性激酶可以是治疗性的。 被用来干扰癌症和其他疾病环境中重要信号传导途径的Cu可用性。

PROJECT SUMMARY/ ABSTRACT Normal physiology relies on the precise coordination of intrinsic cues, in the form of intracellular signal transduction pathways, with extrinsic cues like nutrient availability to balance cell growth and cell death. Transition metals such as copper (Cu) are tightly regulated micronutrients that function as structural or catalytic cofactors for proteins that are critical for normal physiology and development. Aberrant Cu excretion and absorption are manifested in the extremely rare genetic diseases Wilson and Menkes, respectively. The importance of intact Cu homeostatic mechanisms to cell growth control is underscored by the stunted growth and failure to thrive associated with Cu deficiency in Menkes disease patients and the prevalence of cancer in patients with hereditary Cu overload in Wilson disease. Further, Cu is neither created nor destroyed, and therefore low Cu dietary intake may be a contributing factor in impaired wound healing, cardiovascular disease, and non-alcoholic fatty liver disease. However, the dysregulation of a handful of currently identified Cu- dependent enzymes does not fully explain the diverse growth phenotypes associated with alterations in Cu metabolism. Thus, the direct cellular pathways that respond to and or/sense Cu abundance and are integrated to influence cellular proliferation remain undefined. Recent work by our group uncovered an unexpected link between the cellular acquisition of Cu and a mitogenic signaling cascade. In response to proliferative signals, Cu contributes to the amplitude of canonical MAPK signaling through a direct interaction between Cu and the kinases MEK1 and MEK2. This is the first example of Cu directly regulating the activity of a mammalian kinase and has exposed a new signaling paradigm that directly connects Cu to signaling pathway components. Based on our expertise, our group seeks to define the Cu-responsive and -sensing kinase signal transduction pathways to determine the mechanisms by which Cu contributes to pro-proliferative cellular processes that are essential to normal proliferation and are sustained during tumorigenesis. To accomplish our goals, we will utilize a multidisciplinary approach, which includes in vivo mouse models, biochemistry, biophysics, molecular biology, functional genomics, and pharmacologic interventions. Specifically, we will: i) elucidate the molecular mechanisms and cellular contexts that underlie Cu integration into the MAPK pathway, ii) systematically map Cu utilization by pro-proliferative kinase signal transduction pathways, and iii) leverage our experimental approaches and findings to other transition metals and kinase signaling networks in normal homeostasis and cancer. Completion of these studies has the potential to establish Cu availability as an integral component of intracellular communication and elucidate the molecular mechanism underlying this unique connection. Further, identifying novel Cu-dependent kinases can be therapeutically exploited to perturb Cu availability for essential signaling pathways in cancer and other diseases settings.