Towards a structural and temporal understanding of phototransduction

G蛋白偶联受体(GPCR)介导的信号系统的机制仍然是 尽管这些系统在过去的一个世纪里受到了高度关注，但仍未得到解决。这在一定程度上是由于 用分子生物学方法研究天然环境中的膜蛋白的困难 细节。当前提议的重点是应用新的生物物理方法来解开 Gpr介导的信号通路的分子和时间之谜。视紫红质与视觉系统 将是该研究计划的最初重点。这个原型GPCR信号系统提供了几个 将允许应用新的生物物理方法的优点。原子力显微镜将 产生单个分子的高分辨率图像，这将提供结构和组织 系统的信息。单分子力谱将提供有关 视紫红质中稳定蛋白质并促进其功能的分子相互作用。低温电子 断层扫描将获得未受干扰的棒的外部段，以提供关于这一点的结构信息 隔间和在这个场地执行其功能的大分子。荧光共振 能量转移将被用来检测信号蛋白之间的蛋白质相互作用，以监测 动态交互，定义了信令流程和发生信令的时间框架。同舟共济 通过这种独特的方法组合获得的信息将提供分子的关键片段 这些系统当前不可用的信息。这将有助于确定分子机制。 控制GPCRs调控的重要生理过程的信号事件的基础。 G蛋白偶联受体是最大的一类细胞表面蛋白和药物靶标。 目前在市场上。这个蛋白质家族几乎参与了每一个生理过程，而且 这些系统的功能障碍会导致失明、成瘾、糖尿病和心脏病等疾病 疾病。尽管GPCRs很重要，但仍然缺乏对其作用的准确分子描述。 了解这些系统的分子奥秘将导致开发更有效的 治疗方案。

The mechanism underlying G protein-coupled receptor (GPCR)-mediated signaling systems is still unresolved despite the intense focus these systems have received over the past century. This is due in part to the difficulties in studying membrane proteins in their native context by methods that provide molecular details. The focus of the current proposal is to apply novel biophysical methodologies to unravel the molecular and temporal mysteries of GPCR-mediated signaling pathways. Rhodopsin and the visual system will be the initial focus of the research program. This prototypical GPCR signaling system offers several advantages that will allow for the application of novel biophysical approaches. Atomic force microscopy will result in high-resolution images of individual molecules that will provide structural and organizational information of the system. Single-molecule force spectroscopy will provide detailed information on the molecular interactions in rhodopsin that stabilize the protein and promote its function. Cryo-electron tomography will gain access to an unperturbed rod outer segment to provide structural information on this compartment and on the macromolecules that carry out their function at this venue. Fluorescence resonance energy transfer will be utilized to detect protein-protein interactions of signaling proteins to monitor the dynamic interactions that define the signaling process and the timeframe in which this takes place. Together the information obtained by this unique combination of methodologies will provide key pieces of molecular information that is currently unavailable for these systems. This will help define the molecular mechanism underlying the signaling events that govern important physiological processes regulated by GPCRs. G protein-coupled receptors (GPCRs) represent the largest class of cell surface proteins and drug targets currently on the market. This family of proteins is involved in virtually every physiological process, and dysfunctions in these systems can lead to diseases such as blindness, addiction, diabetes, and heart disease. Despite the importance of GPCRs an accurate molecular description of their action is still lacking. Understanding the molecular mysteries of these systems will lead to the development of more effective therapeutic solutions.