Multidrug Resistance-Like Genes and Auxin Transport

多药耐药样基因和生长素转运

• 批准号: 0132803
• 负责人: Edgar Spalding
• 金额: $ 57.33万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-05-01 至 2005-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0132803&HistoricalAwards=false
• 关键词: Multidrug; Resistance; Like; Genes; Auxin

This project is designed to determine the functions of AtMDR1 and other proteins encoded by a group of ABC transporter genes in Arabidopsis that are homologous to multi-drug resistance (MDR) proteins of animals. The animal MDR proteins are most often studied for their roles in the resistance of cancer tumors to chemotherapeutic drugs. This research will investigate the roles these proteins play in plants. Genetic, biochemical, and physiological evidence indicates that at least two of the Arabidopsis MDR proteins participate in the transport of the plant hormone auxin, and thus are important to plant growth and development. The auxin-transport inhibitor NPA binds tightly to AtMDR1 and AtPGP1 proteins. Knockout mutants lacking these proteins have severe defects in polar auxin transport. The phenotypes of the knockout mutants are consistent with abnormal auxin distribution being the cause. The research activities that produced the substantial background information on these two genes will be reiterated to reach some never-before studied genes within the MDR-like subcluster. In addition, biochemical studies will test hypotheses about the mechanism of AtMDR1 function. For example, is it an auxin transporter or a regulator of an auxin transporter? The experimental plan includes characterizing knockout phenotypes, determining the effects of the knockout mutations on auxin distribution, and biochemical studies of the AtMDR1 gene after expression in a heterologous system. The two PIs responsible for the project have complementary areas of expertise and will provide interdisciplinary training for postdoctoral research associates and graduate students. The dissection of these interesting genes genetically, biochemically, and physiologically is expected to provide new insight into the hormonal control of plant growth and development.

本项目旨在确定拟南芥中与动物多药耐药（MDR）蛋白同源的一组ABC转运基因编码的AtMDR1等蛋白的功能。动物多药耐药蛋白在癌症肿瘤对化疗药物的耐药性中的作用是最常被研究的。本研究将探讨这些蛋白在植物中的作用。遗传、生化和生理证据表明，至少有两种拟南芥MDR蛋白参与植物激素生长素的运输，因此对植物的生长发育很重要。生长素运输抑制剂NPA与AtMDR1和AtPGP1蛋白紧密结合。缺乏这些蛋白的敲除突变体在极性生长素运输中存在严重缺陷。基因敲除突变体的表型与生长素分布异常是一致的。研究活动产生了关于这两个基因的大量背景信息，将被重申，以达到耐多药样亚群中一些从未研究过的基因。此外，生化研究将检验关于AtMDR1功能机制的假设。例如，它是生长素转运体还是生长素转运体的调节剂？实验计划包括表征敲除表型，确定敲除突变对生长素分布的影响，以及在异源系统中表达AtMDR1基因后的生化研究。负责该项目的两个pi具有互补的专业领域，并将为博士后研究助理和研究生提供跨学科培训。对这些有趣基因的解剖，从遗传学、生物化学和生理学的角度来看，有望为植物生长发育的激素控制提供新的见解。