Malpighian Tubule Transport Physiology: Mechanism and Regulation

马氏小管运输生理学：机制和调节

• 批准号: 0542797
• 负责人: Klaus Beyenbach
• 金额: $ 65万
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-15 至 2013-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0542797&HistoricalAwards=false
• 关键词: Malpighian; Tubule; Transport; Physiology; Mechanism

This proposal aims to bring genetics, molecular biology and classical physiology to bear on questions of epithelial transport in Malpighian tubules, the kidneys of insects. Studies of adult mosquito Malpighian tubules in the lab of the principal investigator Beyenbach have uncovered new transport phenomena that stimulate research of epithelial transport in biological systems beyond insects. For example, his finding in Malpighian tubules of a) the energizing of diverse epithelial transport systems with the V-type H+ ATPase and not the Na/K ATPase, b) the channel-like behavior of septate (tight) junctions, and c) the rapid regulation of paracellular permeability in the astonishing time domain of seconds, are motivating searches for similar phenomena in vertebrate tissues. The present proposal is a logical extension of the above findings. Hypothesis-driven experiments promise to discover new transport systems while exploring new ideas in transport physiology. In Aim 1, the functional characterization of NHE8 (a Na-H transport protein) he has already cloned in Aedes Malpighian tubules may uncover the first electrogenic Na/H exchanger in any tissue, vertebrate or invertebrate. Aim 2 applies proteomics and highly sensitive mass spec methods with the promise of identifying not only NHE8 but also new proteins, and potentially important new transporters in the apical membrane of the adult Malpighian tubule. In Aim 3 he seeks to a) identify gap junctions, b) determine size and charge selectivity, c) explore the role of gap junctions in cell-to-cell transmission of Ca2+ waves that may mediate the signal transduction of leucokinin, and d) test the novel idea of the metabolic regulation of gap junctions. Three collaborators with an international reputation in molecular biology (Wieczorek), intracellular Ca2+ imaging (Walz), and proteomics (Schooley) have committed their labs to the success of this project. What has motivated this collaboration is the deep understanding that derives from illuminating important research questions from diverse perspectives. Broader Impact. The PI is an enthusiastic teacher and mentor whose lab attracts some of the most gifted and motivated undergraduates. Many make a lifetime commitment to research. As many as 46 undergraduates have been trained in his lab alongside graduate students and post-docs; 19 undergraduates share authorship in refereed journals. Many undergraduates have been accepted in MD-PhD programs, and some have now their own research laboratories. Wanting to know is a powerful drive, perhaps the strongest motivation of the PI and his students. The PI teaches a popular elective Biology course on campus- Mammalian Physiology -to seniors and graduate students. He serves as Director of the Cornell program of study Undergraduate Physiology. The PI is active in international education, helping US students secure summer research positions in Germany, and assisting German students find research opportunities or clinical rotations in the US. The PI is a founding member of the Alexander von Humboldt Association of America (www.avhaa.org). He has received the highest German civilian award, the Bundesverdienstkreuz, for fostering international cooperation in education and research.

这项建议旨在使遗传学，分子生物学和经典生理学承担的问题上的上皮运输的马氏管，肾脏的昆虫。 在首席研究员Beyenbach的实验室中对成年蚊子Malpighian小管的研究发现了新的运输现象，这些现象刺激了昆虫以外生物系统中上皮运输的研究。 例如，他在马尔皮基管中的发现：a）V型H+ ATP酶而不是Na/K ATP酶为各种上皮转运系统提供能量，B）隔膜（紧密）连接的通道样行为，以及c）细胞旁渗透性在惊人的秒时域内的快速调节，激发了在脊椎动物组织中寻找类似现象的研究。 本建议是上述结论的合理延伸。 假设驱动的实验有望发现新的运输系统，同时探索运输生理学的新思路。 在目标1中，他已经在斑蚊马尔皮基管中克隆了NHE 8（一种Na-H转运蛋白）的功能特征，这可能会发现任何组织、脊椎动物或无脊椎动物中的第一个产电Na/H交换剂。 目的2适用于蛋白质组学和高灵敏度的质谱方法，不仅NHE 8，但也识别新的蛋白质，并在成人马氏管的顶端膜的潜在重要的新的转运的承诺。 在目标3中，他试图a）鉴定间隙连接，B）确定大小和电荷选择性，c）探索间隙连接在可能介导白细胞激肽信号转导的Ca 2+波的细胞间传递中的作用，以及d）测试间隙连接的代谢调节的新想法。 在分子生物学（Wieczorek），细胞内Ca 2+成像（Walz）和蛋白质组学（Schooley）方面享有国际声誉的三位合作者已经承诺他们的实验室将成功完成该项目。 这种合作的动机是从不同的角度阐明重要的研究问题所产生的深刻理解。 更广泛的影响。PI是一位热情的教师和导师，他的实验室吸引了一些最有天赋和最有动力的本科生。 许多人一生致力于研究。多达46名本科生与研究生和博士后一起在他的实验室接受培训; 19名本科生在评审期刊上分享作者身份。许多本科生已被MD-PhD项目录取，其中一些现在拥有自己的研究实验室。想要知道是一种强大的动力，也许是PI和他的学生最强烈的动机。PI在校园里教授一门受欢迎的选修生物学课程-哺乳动物生理学-给高年级学生和研究生。 他是康奈尔大学生理学研究项目的主任。 PI积极参与国际教育，帮助美国学生在德国获得暑期研究职位，并帮助德国学生在美国寻找研究机会或临床轮换。PI是美国亚历山大·冯·洪堡协会（www.avhaa.org）的创始成员。 他因促进教育和研究方面的国际合作而获得德国最高平民奖Bundesverdienstkreuz。