Collaborative Research: Ecological and Evolutionary Genetics of P-450 Genes in Desert Drosophila

混合功能氧化酶(MFO‘s)是一种允许昆虫耐受有毒化学物质(如杀虫剂和某些植物化合物)的酶。一些植物通过产生对试图以昆虫为食的动物有毒的化合物来保护自己免受昆虫(和其他食草动物)的伤害。MFO酶通常通过改变化合物的化学结构来使化合物解毒。因此，对混合功能氧化酶的研究将提供有关昆虫如何对杀虫剂和/或有毒植物化学品产生抗药性的信息。这项提议涉及到使用昆虫-植物模型系统。这些昆虫是果蝇属的果蝇，植物是生长在墨西哥索诺兰沙漠的柱状仙人掌。关于这一模型系统的大量背景信息已经获得，包括关于果蝇的生态学和遗传学的数据，以及仙人掌产生的有毒化学物质的鉴定和特征。这项提案中概述的实验将在这些昆虫的混合功能氧化酶和它们对仙人掌植物中有毒化学物质的耐受性之间建立联系。这是对昆虫中产生MFO酶的基因的生态和进化遗传学进行长期研究的必要的第一步。了解这一系统可能会对开发更有效的杀虫剂做出重要贡献。

Mixed-function oxidases (MFO'S) are enzymes that allow insects to tolerate poisonous chemicals such as insecticides and certain plant compounds. Some plants protect themselves from insects (and other herbivores) by making chemical compounds that are toxic to the animals which try and feed on them. The MFO enzymes detoxify chemical compounds, usually by changing their chemical structure. The study of mixed-function oxidase enzymes, therefore, will provide information as to how insects become resistant to insecticides and/or toxic plant chemicals. This proposal involves the use of an insect-plant model system. The insects are fruit-flies of the genus Drosophila, and the plants are columnar cacti which grow in the Sonoran Desert of Mexico. A wealth of background information on this model system has already been obtained including data on the ecology and genetics of the fruit flies and identification and characterization of the toxic chemicals that the cacti produce. The experiments outlined in this proposal will establish a connection between the mixed-function oxidase enzymes in these insects and their tolerance to the poisonous chemicals in the cactus plants. This is a necessary first-step in a long-term study of the ecological and evolutionary genetics of the genes which produce MFO enzymes in insects. Understanding this system could be an important contribution to the development of more effective insecticides.