Molecular basis of plant parasitism by a galling insect

葡萄是世界上最有价值的水果作物，而一种名为根瘤虫的小昆虫是葡萄藤最大的敌人之一。在过去，它几乎摧毁了世界各地的葡萄园。根瘤虫使植物产生专门的结构，在其中生活和繁殖，称为虫胆。这种攻击植物的方式很普遍，并且已经进化了无数次，许多重要的植物害虫都会产生虫害。尽管如此，没有人知道这种昆虫是如何指示植物创造一个有利于害虫的新器官的。这个项目将试图通过检查昆虫在产生虫子时开启或关闭的植物基因来理解这种非凡的能力。查尔斯·达尔文提出，虫胆与水果相似，该项目将专注于植物通常用来创造花朵和果实的基因。假说是，通常与果实生产有关的植物基因被昆虫在根和叶中激活。到目前为止，初步证据支持这一观点。由于植物通常使用激素来调节花朵和果实的生产，因此需要检验的第二个假设是，根瘤菌操纵植物激素来产生瘤。这些想法将通过生产关键基因被阻断的转基因葡萄来得到证实。在这些植物上应该不会形成虫胆。该项目的发现不仅将解释一个长期存在的自然界之谜；它们还将为开发抗虫葡萄提供必要的遗传信息。该项目是生态学家、昆虫学家、植物生物学家和生物技术专家之间的独特合作。它的成果将通过与密苏里州新闻学院和葡萄饲养者的合作向公众推广。PI是McNair和Express计划的非常积极的支持者，相当数量的本科生和K-12教师也将参与其中。

Grapes are the world's most valuable fruit crop, and a small insect called phylloxera is one of the grapevine's worst enemies. In the past it has almost wiped out vineyards worldwide. Phylloxera causes the plant to create specialized structures in which it lives and reproduces, called galls. This way of attacking plants is widespread and has evolved numerous times, and many important plant pests are gall-makers. Still, no one has any idea how the insect instructs the plant to create a new organ that benefits the pest. This project will attempt to understand this remarkable ability by examining the plant genes that are turned on or off by the insect in creating a gall. Charles Darwin suggested that galls resemble fruits and this project will focus on genes the plant normally uses to create flowers and fruits. The hypothesis is that plant genes normally involved in fruit production are activated by the insect in roots and leaves. Preliminary evidence to date supports that view. Since plants normally regulate flower and fruit production using hormones, a second hypothesis to be tested is that phylloxera manipulates plant hormones to create galls. These ideas will be confirmed by producing genetically-modified grapevines with key genes blocked. It should be impossible for galls to form on these plants. Findings from this project will not only explain a long-held mystery of nature; they will also provide the genetic information necessary for developing insect-resistance grapevines. The project is a unique collaboration among ecologists, entomologists, plant biologists and biotechnologists. Its results will be extended to the public via a collaboration with the Missouri School of Journalism and to grapevine breeders. The PIs are very active supporters of McNair and EXPRESS program students and a substantial number of undergraduates and K-12 teachers will also participate.