Regulatory Roles of Zinc Fluxes in Metalloprotein Occupancy and Cell Cycle Progression

项目总结 该项目研究了调节细胞的金属蛋白的结构、光谱、功能和机制。 细胞内锌浓度程序性波动的周期延长。锌熔剂有 最近被发现是人类生理中的关键调节事件，包括皮质神经元功能， 免疫反应、受精和胰岛素分泌。尽管它在这些深刻的生理学中扮演着明显的角色， 锌的生物化学作用还不是很清楚。人们对其无机化学知之甚少。 金属蛋白参与介导细胞对锌熔剂、锌的反应的指导机制 运输途径，或特定金属蛋白受体在信号事件中的作用。来解释和 最终干预疾病所引起的这类通路的中断，首先必须阐明根本 锌依赖的转换事件的分子机制。 虽然锌传统上被视为参与蛋白质结构和酶催化的静态辅因子， 最近的研究支持这一观点，即调控蛋白中的锌结合位点对 锌的可用性，并以调节关键细胞事件的方式开启和关闭。我们将检验这一假设 调节锌的通量通过特定的受体对哺乳动物的细胞周期起指导作用。 调解的过程。这一假设基于多条证据，包括：(1)数据显示 单细胞周期不同时间点锌的波动分布；(2)活细胞成像显示 锌波的运动；以及(3)物理化学方法显示锌与特定的 各种因素。这项提议的首要目标是使用生化和光谱方法来 了解锌的流入和流出是如何控制细胞周期的。用于探测和控制的化学品工具 锌的浓度将被创造出来，以加深我们对锌生理的理解。此外，我们还将 利用X射线吸收和发射光谱、核磁共振和质谱学中的新兴技术 了解锌的化学环境，并探索含锌蛋白质在锌中的占有率 调节细胞周期进程。综上所述，这些研究的结果将阐明锌的强大作用 细胞周期中的信号通量。

PROJECT SUMMARY This project examimes the structure, spectroscopy, function, and mechanism of metallproteins that regulate cell cycle progresion in response to programmatic fluctuations in intracellular zinc concentration. Zinc fluxes have recently been discovered to be key regulatory events in human physiology, including cortical neuron function, immune response, fertilization, and insulin secretion. Despite its apparent roles in these profound physiologies, the biochemistry of zinc action is not well understood. Little is known regarding the inorganic chemistry of metalloproteins involved in the instructive mechanisms that mediate cellular responses to zinc fluxes, zinc trafficking pathways, or the role of specific metalloprotein receptors in signaling events. To interpret and eventually intervene in diseases caused by disruption of such pathways, we must first elucidate the fundamental molecular mechanisms of zinc-dependent switching events. While zinc has traditionally been viewed as a static cofactor involved in protein structure and enzyme catalysis, recent studies support the idea that zinc binding sites in regulatory proteins respond to transient fluctuations in zinc availability and are switched on and off in ways that regulate key cellular events. We will test the hypothesis that regulatory zinc fluxes exert instructive control over the mammalian cell cycle through specific, receptor- mediated processes. This hypothesis is based on multiple lines of evidence, including: (1) data showing fluctuations zinc distribution at various points in the cell cycle for single cells; (2) live cell imaging demonstrating the movement of waves of zinc; and (3) physicochemical approaches showing colocalization of zinc with specific factors. The overarching objective of this proposal is to use biochemical and spectroscopic approaches to understand how the influx and efflux of zinc exert control over the cell cycle. Chemicals tools to probe and control the concentration of zinc will be created to further our understanding of zinc physiology. In addition, we will leverage emerging techniques in X-ray absorption and emission spectroscopy, NMR, and mass spectrometry to understand the chemical environment of zinc and probe the zinc occupancy of zinc-containing proteins that regulate cell cycle progression. Taken together, the results from these studies will elucidate a robust role for zinc signaling fluxes during the cell cycle.