FUNCTIONAL DOMAINS OF K+ CHANNEL SUBUNIT PROTEINS

K 通道亚基蛋白的功能域

• 批准号: 2269521
• 负责人: Paul Pfaffinger
• 金额: $ 20.78万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-05-01 至 1997-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2269521
• 关键词: Xenopus oocyte; electrophysiology; gene expression; membrane biogenesis; membrane structure; molecular biology; neurons; potassium channel; protein structure function; voltage gated channel

The physiological properties of a neuron and other cells of the body are strongly affected by the variety and abundance of potassium channels expressed in the cell. A large number of K+ channel genes are being cloned that apparently code for single subunits of multisubunit K+ channel proteins, but how are these subunit proteins targeted to form the variety of K+ channel proteins found in a cell. A specific question these experiments will address is whether subunit primary structures guide K+ channel assembly in forming the electrical properties of neurons. The Preliminary Results describe experiments that identify a domain of a Shaker Subfamily K+ channel protein (T1 domain) that appears to be a self organizing tetramerization center; tetramerization is thought to be a critical step in the formation of K+ channels by K+ channel subunit proteins. This T1 domain does not appear to interact with a K+ channel clone from another gene subfamily. The Specific Aims of this grant are: 1) Further Characterization of the Shaker Subfamily T1 N-Terminal Tetramerization Domain, 2) Identification of Other domains Involved in K+ Channel Subunit Multimerization, 3) Characterization of the Subfamily Dependent Differences in the T1 Domain and Testing Whether T1 Subfamily Specificity is Dominant, and 4) Examination of the Role of T1 Domain Compatibility in the Formation of Functional K+ Channel Proteins. The experiments to accomplish these Specific Aims rely exclusively on techniques or methods that are presented in the Preliminary Results or are being used currently in the lab. The general approach is to clone subfragments of different K+ channel subunit proteins that are thought to encode T1 domains, and to test for their function and subfamily specificity. A series of mutagenesis experiments will identify specific regions and amino acid residues that are critical for T1 domain tetramerization and subfamily specificity. Finally, a set of chimeric K+ channel subunit proteins will be created, with swapped T1 domains, to test for the importance of T1 in determining subunit protein interaction and formation of homomultimeric and heteromultimeric K+ channels. Because K+ channel proteins are an increasingly important target for drugs to treat asthma, high blood pressure, diabetes, multiple sclerosis, epilepsy and potentially a host of other disorders, these experiments will benefit health research by providing critical information about the events and domains of K+ channel subunit proteins that are involved in forming the ion channel.

神经元和身体其他细胞的生理特性是 受钾离子通道种类和丰度的影响 在细胞中表达。 大量的K+通道基因正在被 克隆了一个明显编码多亚基K+的单亚基的基因， 通道蛋白，但这些亚基蛋白如何靶向形成 在细胞中发现的多种K+通道蛋白。 某一个问题所 这些实验将解决的问题是， 引导K+通道组装形成电性能 神经元 初步结果描述了确定一种 Shaker亚家族K+通道蛋白（T1结构域）， 是一个自组织的四聚中心;四聚是 被认为是由K+形成K+通道的关键步骤 通道亚基蛋白。 这个T1结构域似乎不与 与来自另一个基因亚家族的K+通道克隆。 具体目标 该补助金的主要内容是：1）进一步表征振动子家族 T1 N-末端四聚化结构域，2）其它结构域的鉴定 参与K+通道亚基多聚化，3）表征 T1结构域中的亚家族依赖性差异和测试是否 T1亚家族特异性占主导地位，以及4）T1亚家族特异性的作用的检查 功能性钾通道形成中的T1结构域相容性 Proteins. 实现这些特定目标的实验依赖于 专门针对技术或方法， 初步结果或目前正在实验室中使用。 总 方法是克隆不同K+通道亚基的亚片段 被认为是编码T1结构域的蛋白质，并测试其 功能和亚家族特异性。 一系列突变实验 将确定关键的特定区域和氨基酸残基 T1结构域四聚体和亚家族特异性。 最后，一套 将创建嵌合K+通道亚基蛋白，并交换T1 结构域，以测试T1在确定亚基蛋白质中的重要性 同源多聚体和异源多聚体K+相互作用和形成 渠道 由于K+通道蛋白是一种越来越重要的 治疗哮喘、高血压、糖尿病、多种 硬化症、癫痫和其他潜在的疾病，这些 实验将通过提供关键的 关于K+通道亚基蛋白的事件和结构域的信息 参与形成离子通道。