CAREER: Phylogeny and Evolution of Armored Scale Insects (Hemiptera: Diaspididae) and Their Bacterial Endosymbionts

摘要.NormarkDEB 0447880甲壳虫在许多方面都是不同寻常的生物。雄性会飞，看起来像普通的昆虫，但雌性是没有翅膀，没有腿的斑点。甲壳虫有奇怪的遗传，雄性从双亲的染色体开始生活，但失去了父亲的染色体，只遗传了母亲的染色体。它们有奇怪的解剖和营养，没有肠道连接嘴和肛门。马萨诸塞州大学研究生马修·格鲁威尔最近发现，甲壳虫也与不寻常的细菌有关--与大多数食汁性昆虫中发现的变形杆菌不同，甲壳虫有黄杆菌。细菌在宿主的营养和遗传中的作用是当前研究的活跃领域，这一领域可以通过甲壳虫不寻常的营养、遗传学和细菌之间的联系来阐明。但甲壳虫的简化解剖结构，以及随之而来的识别、分类和理解它们的进化关系的困难，阻碍了进展。在这个项目中，首席研究员和他的学生将在早期研究的基础上，对250种甲壳虫的四种不同基因进行DNA测序。他们还将对与介壳虫相关的细菌的DNA进行测序，并调查介壳虫组织中细菌的出现位置。DNA序列将被用来推断进化树，这将揭示这些昆虫不寻常特征的进化以及它们与细菌共同进化的本质，并为它们的分类提供更可靠的基础。甲壳虫是美国和世界上除最冷地区外树木和灌木的主要害虫，特别是对水果和坚果作物和观赏植物的破坏。该项目将导致对这些昆虫进行更好的分类，这将有助于管理人员预测重要的生物学特征，如天敌。最终，这些数据将允许通过“DNA条形码”识别甲壳虫。这在甲壳虫的情况下尤其有用，因为目前只有一个生活期(成年雌性)可识别。该项目直接支持教育，因为几乎所有的资金都用于支持研究生和本科生及其研究。为了培养直接的本科生教育和参与该项目，首席研究员正在教授一门新的本科生课程，名为“分子生物多样性实验室”，该课程将教授分子系统学领域的基本原理，以及相关的实验室和计算机技能。

The abstract.NormarkDEB 0447880Armored scale insects are unusual organisms in many ways. The males fly, and look like ordinary insects, but the females are wingless, legless blobs. Armored scale insects have strange genetics, in which males start life with chromosomes from both parents, but lose their fathers' chromosomes and pass on only their mothers'. They have strange anatomy and nutrition, with no gut connecting mouth to anus. UMass grad student Matthew Gruwell recently discovered that armored scale insects are also associated with unusual bacteria -- unlike the Proteobacteria found in most sap-feeding insects, armored scale insects have Flavobacteria. The role of bacteria in the nutrition and genetics of their hosts are vibrant areas of current research, and this field may be illuminated by the connections betwen armored scale insects' unusual nutrition, genetics, and bacteria. But the simplified anatomy of armored scale insects, and consequent difficulty of identifying them, classifying them, and understanding their evolutionary relationships, has hindered progress. In this project, the principal investigator and his students will sequence DNA from four different genes of 250 species of armored scale insects, expanding upon an earlier study. They will also sequence DNA from bacteria associated with the scale insects, and investigate where in the scale insects tissues the bacteria occur. The DNA sequences will be used to infer evolutionary trees which will shed light on the evolution of the unusual characters of these insects and the nature of their co-evolution with bacteria, as well as providing a sounder basis for their classification.Armored scale insects are major pests of trees and shrubs in the US and in all but the coldest regions of the world, especially damaging fruit and nut crops and ornamentals. This project will lead to a better classification of these insects, which will help managers predict important biological features such as natural enemies. Ultimately these data will permit armored scale insects to be identified through "DNA barcoding." This will be especially useful in the case of armored scale insects, since currently only one life stage (adult females) is identifiable. The project directly supports education in that almost all of the funds go to support graduate and undergraduate students and their research. To foster direct undergraduate education and participation in the project, the principal investigator is teaching a new undergraduate course entitled "Molecular Biodiversity Lab," that will teach the basic principles of the field of molecular systematics, and the associated lab and computer skills.