Mass spectrometric studies on potassium channels

描述（由申请人提供）：电压依赖性离子通道是 有助于产生膜电位、受体电位和 动作电位它们是分子构建模块， 神经科学中许多细胞的基本特征：兴奋性。这些 蛋白质参与所有兴奋性神经元的生理学和病理生理学。 组织，是许多疾病过程的基础，包括癫痫和心律失常， 是临床用药的主要靶点。尽管 这些蛋白质的明显生物学和临床重要性，我们仍然知道， 对它的结构知之甚少。虽然取得了重大进展， 在理解钾离子通道的离子渗透时， 这些必需的蛋白质在结构上仍然没有得到解决。 该提案探索了一种解决结构性问题的新技术 包括离子通道和其他膜蛋白。我们将使用一个组合 半胱氨酸扫描诱变，烷基化，和质谱研究 两个钾通道KcsA和Shaker的结构方面。我们称之 新技术如定点质量标记。长期目标是 建议是提供有关功能的低分辨率结构信息， 离子通道这项建议是高风险的，因为我们还不知道 这项技术是否会发挥其潜力，并证明是一个有用的 结构工具。如果成功的话，定位标记也许能够 为了解许多罕见的膜的总体结构提供了重要的见解 proteins.预计这项研究的结果将提供新的 深入了解振动筛的总体结构布局。

DESCRIPTION (provided by applicant): Voltage-dependent ion channels are instrumental in the generation of membrane potential, receptor potential, and action potential. They are the molecular building blocks for what is an essential characteristic of many cells in neuroscience: excitability. These proteins are implicated in the physiology and pathophysiology of all excitable tissues, underlie many disease processes including epilepsies and arrhythmias, and are major targets of essential drugs used in clinical medicine. Despite the obvious biological and clinical importance of these proteins, we still know relatively little about their structure. Although important progress has been made in understanding ion permeation in potassium channels, large parts of these essential proteins remain structurally unresolved. This proposal explores a novel technique for addressing structural questions involving ion channels and other membrane proteins. We will use a combination of cysteine scanning mutagenesis, alkylation, and mass spectrometry to study structural aspects of two potassium channels, KcsA and Shaker. We refer to this novel technique as site-directed mass tagging. The long-term goal of this proposal is to provide low-resolution structural information about functional ion channels. The proposal is high risk in the sense that we do not yet know whether the technique will fulfill its potential and prove to be a useful structural tool. If successful, however, site-directed mass tagging may be able to provide important insight into the gross structure of many rare membrane proteins. It is anticipated that results from this study will provide new insight into the general structural layout of Shaker.