Examining the Intersection of Transitional Metals and Kinase Signal Transduction Networks

项目摘要/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，外在的信号，如营养供应，以平衡细胞生长和细胞死亡。 铜等过渡金属是受到严格监管的微量营养素，具有结构性或催化性作用 对正常生理和发育至关重要的蛋白质的辅因子。异常的铜排泄和 吸收分别表现在极其罕见的遗传病威尔逊和门克斯。这个 生长受阻强调了完整的铜平衡机制对细胞生长控制的重要性。 与孟克斯病患者的铜缺乏和癌症患病率有关的发育不良 遗传性铜超载的肝豆状核变性患者。此外，铜既不是被创造的，也不是被摧毁的，而且 因此，低铜饮食摄入量可能是伤口愈合障碍、心血管疾病、 和非酒精性脂肪性肝病。然而，目前发现的几种铜-铜的失调 依赖酶不能完全解释与铜变化相关的不同生长表型 新陈代谢。因此，响应和/或感知铜丰度的直接细胞通路是整合的 影响细胞增殖的机制尚不明确。我们小组最近的研究发现了一个意想不到的联系 在细胞获得铜和有丝分裂信号级联之间。作为对增殖信号的响应， 铜通过铜与MAPK之间的直接相互作用对规范的MAPK信号的幅度做出贡献 激活MEK1和MEK2。这是铜直接调节哺乳动物蛋白激酶活性的第一个例子。 并揭示了一种新的信号模式，将铜与信号通路组件直接联系起来。基座 根据我们的专业知识，我们的团队试图定义铜响应和传感的激酶信号转导 确定铜促进促增殖细胞过程的机制的途径 对正常增殖至关重要，并在肿瘤形成过程中持续存在。为了实现我们的目标，我们将 利用多学科方法，包括活体小鼠模型、生物化学、生物物理学、分子 生物学、功能基因组学和药理学干预。具体来说，我们将：i)阐明 铜整合到MAPK途径的分子机制和细胞环境，II) 通过促增殖激酶信号转导通路系统地定位铜的利用，以及iii) 利用我们的实验方法和发现来研究其他过渡金属和激酶信号 正常动态平衡和癌症的网络。这些研究的完成有可能建立起 可用性作为细胞内通讯的一个组成部分并阐明其分子机制 在这种独特的联系下。此外，鉴定新的铜依赖的激酶可以在治疗上 被利用来扰乱铜在癌症和其他疾病环境中的基本信号通路的可用性。

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.