Highly Reduced Genomes of Coresident Bacterial Symbionts of Xylem-Feeding Insects: Ecological and Evolutionary Implications

在南希·A·莫兰博士和罗德·荣博士的指导下，亚利桑那大学获得了一项拨款，用于对高度简化的细菌基因组进行测序，这些细菌以共生体的形式生活在以木质部为食的昆虫中。共生细菌对许多动植物的发育和繁殖至关重要，目前正在利用基因组方法探索它们的作用。在许多动物中，共生体提供食物所缺乏的营养。许多以植物为食的昆虫含有正常发育和繁殖所需的特殊细菌共生体。这些细菌过去一直很难研究，因为它们不能在宿主之外生长。然而，现在能够对它们的基因组进行测序，可以对这些生物体在宿主体内的功能有重大的新理解。这个项目将确定和分析共生体的基因组序列，这些共生体生活在两种被称为神枪手的昆虫物种和一种唾沫虫物种中，所有这些昆虫都以植物木质部和许多农作物的媒介疾病为食。每一个宿主都含有一对共生细菌物种。研究细菌共生体基因组的莫兰博士和经营着一家专注于植物的测序和基因组分析中心的荣博士将在这次合作中使用新的基因组序列确定方法。对基因组序列的分析可能会揭示共生体生物学的关键方面，这些方面可能有助于控制寄主，而寄主是重要的农业害虫。这些成果将被纳入正在进行的大学生以及高中教师和学生的科学教育和外展项目中。

A grant has been awarded the University of Arizona under the direction of Dr. Nancy A. Moran and Dr. Rod Wing to sequence the highly reduced genomes of bacteria that live as symbionts in xylem-feeding insects. Symbiotic bacteria are critical to the development and reproduction of many plants and animals, and their roles are now being explored using genomic approaches. In many animals, symbionts provision nutrients that are lacking in food. Many plant-feeding insects contain specialized bacterial symbionts that are required for normal development and reproduction. These bacteria have been difficult to study in the past because they cannot be grown outside their hosts. However, the capability to sequence their genomes now allows major new understanding of how these organisms function within their hosts. This project will determine and analyze the genomic sequence of symbionts that live in two insect species called sharpshooters, and a spittlebug species, all of which feed on plant xylem and that vector diseases of many crop plants. Each of these hosts contains a pair of symbiotic bacterial species. New approaches to genome sequence determination will be used in this collaboration between Dr. Moran, who investigates bacterial symbiont genomes, and Dr. Wing, who runs a sequencing and genome analysis center focused on plants. Analysis of the genomic sequence potentially will reveal critical aspects of symbiont biology that can be useful in the control of the hosts, which are significant agricultural pests. Results will be integrated in ongoing science education and outreach projects for college students as well as high school teachers and students.