C. Elegans and Mitochondrial K+ Channels

C. 线虫和线粒体 K 通道

基本信息

批准号：
8010191
负责人：
Paul S Brookes
金额：
$ 30.44万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-01-01 至 2013-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8010191
关键词：
Acute myocardial infarction Address Anesthetics Animal Model Attenuated Bioenergetics Blood Vessels Caenorhabditis elegans Candidate Disease Gene Cardiac Cardiac Myocytes Cardiovascular Physiology Cause of Death Cell Death Cells Cessation of life Chimeric Proteins Complex Cyclic AMP-Dependent Protein Kinases Data Databases Development Exposure to Gene Mutation Genes Genetic Genetic Models Goals Homeostasis Hypoxia Injury Inner mitochondrial membrane Ion Channel Ions Ischemia Ischemic Preconditioning Knockout Mice Laboratories Lead Life Malonates Mammals Measures Mediator of activation protein Membrane Mitochondria Mitochondrial Proteins Modeling Molecular Morbidity - disease rate Mutation Myocardial Infarction Nematoda Neurologic Deficit Neurons Organism Orthologous Gene Oxygen Pathogenesis Perfusion Physiology Potassium Potassium Channel Process Production Reagent Regulation Reperfusion Injury Reperfusion Therapy Research Personnel Role Signal Pathway Signal Transduction Signaling Molecule Stroke Succinate Dehydrogenase Surface System Testing Time Tissues Transmembrane Transport United States atpenin A5 cell type computerized data processing conditioning design experience genetic resource improved meetings mortality mutant novel preconditioning public health relevance research study response therapeutic target trafficking

项目摘要

DESCRIPTION (provided by applicant): Acute myocardial infarction is a leading cause of death throughout the world, while stroke is the third leading cause of death in the United States. Ischemia-reperfusion injury associated with these conditions can lead to permanent tissue damage or neurologic deficits. It is well recognized that non-lethal exposure to ischemia for short periods of time however, elicits a proadaptive response that protects cells from subsequent ischemic injury in a process referred to as preconditioning. Mitochondria are central to the pathogenesis of ischemia- perfusion injury and are believed to be a major target for preconditioning. In particular, ion channels in the inner mitochondrial membrane that transport potassium (KATP and KCa channels) are believed to attenuate the mitochondrial cell death response following preconditioning. The molecular identity of these channels is controversial. The major goal of this proposal is to unambiguously identify the mitochondrial KATP and KCa channels, and a second goal is to identify signaling processes that regulate channel activity in the mitochondria in response to preconditioning. The experiments designed to meet these goals will be carried out in the nematode C. elegans. It has recently been shown that preconditioning can protect this genetic model organism from hypoxic injury and death. Moreover, we have found that C. elegans express functional KATP and KCa channels in their mitochondria. We propose to combine the strengths of two investigators, one with extensive experience in mitochondrial bioenergetics and cardiovascular physiology, and the other in nematode ion channel physiology, to test the hypothesis that KATP and KCa channel regulation is an evolutionarily conserved mechanism that contributes to preconditioning in C. elegans. We will utilize the vast array of genetic resources available in C. elegans to screen strains containing mutations in candidate genes for channel activity in purified mitochondria, for channel regulation via conserved signaling pathways, and for their ability to be preconditioned. The results from these experiments will improve our ability to develop protective therapeutics targeted at channels or upstream regulators and designed to mimic the effects of preconditioning in mammals. PUBLIC HEALTH RELEVANCE: Reduced oxygen availability causes cellular damage and death, particularly in neurons (via stroke) or cardiac myocytes (via heart attack). However, brief sub-lethal exposure to low oxygen can lead to proadaptive mechanisms that protect against subsequent decreases in oxygen. This process is called "preconditioning" and acts as an evolutionarily conserved early warning system in all cell types and organisms examined so far. We propose to determine the molecular identity of membrane ion transporters that have been implicated in this proadaptive conditioning via their function in the mitochondria and to study their regulation using the genetic model organism C. elegans. The identification of these molecules will help in the development of new therapies for heart attack and stroke.

描述（由申请人提供）：急性心肌梗塞是全世界死亡的主要原因，而中风是美国第三大死亡原因。与这些病症相关的缺血再灌注损伤可导致永久性组织损伤或神经功能缺损。然而，众所周知，短时间的非致命性缺血暴露会引发一种促适应性反应，在称为预处理的过程中保护细胞免受随后的缺血性损伤。线粒体是缺血-灌注损伤发病机制的核心，被认为是预处理的主要目标。特别是，线粒体内膜中转运钾的离子通道（KATP 和 KCa 通道）被认为可以减弱预处理后的线粒体细胞死亡反应。这些通道的分子特性存在争议。该提案的主要目标是明确识别线粒体 KATP 和 KCa 通道，第二个目标是识别响应预处理而调节线粒体中通道活动的信号传导过程。为实现这些目标而设计的实验将在线虫中进行。最近的研究表明，预处理可以保护这种遗传模型生物免受缺氧损伤和死亡。此外，我们发现线虫在其线粒体中表达功能性 KATP 和 KCa 通道。我们建议结合两名研究人员的优势，一名在线粒体生物能量学和心血管生理学方面拥有丰富的经验，另一名在线虫离子通道生理学方面拥有丰富的经验，以检验 KATP 和 KCa 通道调节是一种进化上保守的机制，有助于预处理的假设。 C.线虫。我们将利用秀丽隐杆线虫中可用的大量遗传资源来筛选含有候选基因突变的菌株，以了解纯化线粒体中的通道活性、通过保守信号通路进行的通道调节以及它们的预处理能力。这些实验的结果将提高我们开发针对通道或上游调节因子的保护性疗法的能力，并旨在模拟哺乳动物预处理的效果。公共卫生相关性：氧气供应量减少会导致细胞损伤和死亡，特别是神经元（通过中风）或心肌细胞（通过心脏病发作）。然而，短暂的亚致死暴露于低氧环境可能会产生促适应机制，防止随后的氧气减少。这个过程被称为“预处理”，并且在迄今为止检查的所有细胞类型和生物体中充当进化上保守的早期预警系统。我们建议通过其在线粒体中的功能来确定参与这种促适应性调节的膜离子转运蛋白的分子身份，并使用遗传模型生物线虫来研究它们的调节。这些分子的鉴定将有助于开发心脏病和中风的新疗法。