STRUCTURE AND FUNCTION OF MAMMALIAN POTASSIUM CHANNELS

哺乳动物钾通道的结构和功能

• 批准号: 3415036
• 负责人: JOHN P ADELMAN
• 金额: $ 19.52万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-02-01 至 1995-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3415036
• 关键词: Amphibia; chemical structure function; divalent cations; egg /ovum; electrophysiology; laboratory rat; molecular cloning; molecular dynamics; pharmacokinetics; polymerase chain reaction; potassium channel; single cell analysis; site directed mutagenesis; tetraethylammonium compound

The functions of potassium channels are central to the properties of all excitable mammalian cells. Electrophysiological and pharmacokinetic studies have defined many different classes of potassium channels. However, the molecular basis of this diversity, and the relationships between channel structure and function remain unknown. Through the use of molecular cloning and electrophysiology, we have isolated, characterized, and expressed in frog oocytes a mammalian potassium channel from rat hippocampus. Surprisingly, the properties of this channel do not fit any single kind of channel as defined by classical methods. The major goal of the research proposed here is to further our understanding of the molecular basis of variations among the different classes of mammalian potassium channels. First, we will clone, characterize, and express in frog oocytes mammalian potassium channels, both voltage and ligand gated, with distinct structural and functional properties. The different kinds of channels will be compared to those known by classical methods. Second, structure-function studies, using site directed mutagenesis, will be performed using a range of potassium channels with distinct properties. Site directed mutant studies of whole, reconstructed channels will be conducted in oocytes. Third, ancillary factors which may influence channel functions will be investigated. Fourth, subunit-specific probes will be generated, based on established nucleotide sequences, and employed in in situ hybridization studies to map the expression patterns of potassium channels in the brain. By studying the structure and function of mammalian potassium channels in this way, we hope to answer questions regarding the molecular basis of potassium channel diversity and the significance of this diversity to the basic properties of excitable mammalian cells.

钾通道的功能是所有特性的核心 可激发的哺乳动物细胞。电生理和药代动力学 研究定义了许多不同类别的钾通道。 但是，这种多样性的分子基础和关系 通道结构和功能之间仍然未知。通过使用 分子克隆和电生理学，我们已经分离，表征， 并在青蛙卵母细胞中表达了大鼠的哺乳动物钾通道 海马。令人惊讶的是，此通道的属性不适合任何 通过经典方法定义的单一通道。 这里提出的研究的主要目标是进一步 理解不同的变异的分子基础 哺乳动物钾通道的类别。首先，我们将克隆 表征并在青蛙卵母细胞中表达哺乳动物钾通道， 电压和配体门控，具有独特的结构和功能 特性。将不同种类的渠道与这些渠道进行比较 通过经典方法知道。第二，结构功能研究，使用站点 定向诱变，将使用一系列钾进行 具有不同特性的通道。站点指导整体突变研究， 重建的通道将在卵母细胞中进行。第三，辅助 可能会影响可能影响通道功能的因素。 基于已建立的第四个亚基特异性探针将生成 核苷酸序列，并在原位杂交研究中用于绘制 大脑中钾通道的表达模式。 通过研究哺乳动物钾通道的结构和功能 这样，我们希望回答有关分子基础的问题 钾渠道的多样性及其多样性对 可激发哺乳动物细胞的基本特性。