CAGED PROBES FOR CELLULAR PHYSIOLOGY

描述(申请人提供)：“笼状”分子是生物活性分子的光敏但暂时惰性的前体。光吸收将前体转化为具有全部生物活性的分子。由于光束可以很容易地聚焦和操纵，而且光化学反应非常快，笼子里的分子是利用光以异常高的空间和时间分辨率操纵生物的多功能工具。长期目标是开发一系列新的光化学工具，使细胞生理学家能够利用光来探测和控制活细胞和组织中的动态信号过程。建议的研究有四个重点：1)开发新的笼子，a)被光强烈激活，b)在光解时显示出快速的产物释放动力学，c)在光解时产生高产量的产物，d)在没有光的情况下化学和代谢稳定。2)开发用于细胞信号传递的新探针，特别是笼状神经递质、脂质信使，以及允许神经递质受体和转运体以及离子通道的光化学敲除的探针。3)开发和优化两种细胞内钙信号探针：笼式钙和笼式“抗钙”，分别用于用光快速产生和消融细胞内钙信号。4)将所开发的探针应用于神经末梢和树突的信号处理、突触可塑性和细胞兴奋性的钙调节等细胞生理学研究。

DESCRIPTION (provided by applicant): A "caged" molecule is a photosensitive, but temporarily inert, precursor of a biologically active molecule. Light absorption transforms the precursor into a molecule with full bioactivity. Because a light beam can be easily focused and steered, and photochemical reactions are extremely fast, caged molecules are versatile tools for using light to manipulate biology with exceptionally high spatial and temporal resolution. The long-term objective is to develop a broad spectrum of novel photochemical tools that will enable cellular physiologists to use light to probe and control dynamic signaling processes in living cells and tissues. The proposed research has four foci: 1) Develop new "cages" that a) are strongly activated by light, b) show fast kinetics of product release on photolysis, c) give high yield of product when photolyzed, and d) are chemically and metabolically stable in the absence of light. 2) Develop new probes for cellular signaling, specifically cage neurotransmitters, lipid messengers, as well as probes that permit "photochemical knock-out" of neurotransmitter receptors and transporters, and ion channels. 3) Develop and optimize two probes of intracellular calcium signaling: a caged calcium and a caged "anti- calcium" for using light to rapidly generate and ablate intracellular calcium signals, respectively. 4) Apply the developed probes to cellular physiology research in the areas of signal processing by nerve terminals and dendrites, synaptic plasticity, and calcium regulation of cell excitability.