DISSERTATION RESEARCH: Localizing the translational machinery of an obligate symbiosis

内共生是一个细胞在另一个细胞内稳定居住的过程，偶尔允许新的财团利用以前未开发的资源。例如，植物能够利用太阳的能量是因为细菌和真核细胞之间的古老内共生关系。同样，许多以汁液为食的昆虫其中一些是毁灭性的农作物害虫依靠细菌内共生体生存。昆虫内共生体是有用的模型，因为它们处于一个中间年龄：足够老，可以显示出许多与线粒体和叶绿体相似的地方，但足够近，可以保留明显的细菌特征。因此，研究昆虫-细菌共生关系可以深入了解建立和维持细菌-宿主关系的力量和机制。这项提议包括通过一个儿童科学项目来教授细菌共生。专性昆虫内共生体与其自由生活的祖先相比具有高度减少的基因组，其已经丢失了许多基因。与细胞器类似，一些内共生体基因组包含的基因比支持细胞生命所需的基因要少。该项目将使用Hodgkinia内共生菌作为模型，研究基因组减少的共生菌如何在如此少的基因下发挥作用。PI将使用最先进的光学和电子显微镜相结合的方法研究支持霍奇金病的昆虫组织的结构和功能，目的是更好地了解昆虫宿主是否和/或如何提供具有基本细胞成分的共生体。获奖者将回答这些问题，通过标记蛋白质和RNA定位这些基因产物在共生体窝藏组织。本研究的结果对于理解宿主-细菌相互作用、细胞器的进化以及改进昆虫组织的显微镜方法具有重要意义。

Endosymbiosis is a process whereby one cell takes up stable residence within another cell, occasionally allowing the new consortia to harness previously unexploited resources. For example, plants are able to use the Sun's energy because of an ancient endosymbiosis between a bacterium and a eukaryotic cell. Similarly, many sap-feeding insects-some of which are devastating crop pests-rely on bacterial endosymbionts to survive. Insect endosymbioses are useful models because they are of an intermediate age: old enough to show many parallels to mitochondria and chloroplasts, but recent enough to retain a clear bacterial character. Studying insect-bacterial symbioses thus provide insight into the forces and mechanisms involved in establishing and maintaining bacteria-host relationships. This proposal includes outreach through a children's science program to teach about bacterial symbioses. Obligate insect endosymbionts have highly reduced genomes that have lost many genes compared to their free-living ancestors. Similar to organelles, some endosymbiont genomes contain fewer genes than thought necessary to support cellular life. This project will use the cicada endosymbiont Hodgkinia as a model to study how symbionts with reduced genomes function with so few genes. The PIs will investigate the structure and function of Hodgkinia-supporting insect tissues using a combination of cutting edge light and electron microscopy, with the aim of better understanding if and/or how insect hosts provide symbionts with essential cellular components. The awardee will answer these questions by labeling cicada proteins and RNAs to localize these gene products within symbiont-harboring tissues. The results of this study are important for understanding host-bacterial interactions, the evolution of organelles, and for improving microscopy methods on insect tissues.