Development of a Dictyostelium Discoideum Model for Genomic and Transcriptomic Analysis of Conserved Interactions with Enteric Pathogens

 描述（由申请人提供）：哺乳动物先天免疫细胞通过吞噬作用吸收并杀死入侵细菌;然而，致病性细菌菌株已经进化出在吞噬细胞吸收后逃避杀死的手段，以逃避先天免疫防御。土壤变形虫盘基网柄阿米巴也利用吞噬作用吸收细菌用于营养目的。土壤中的细菌已经进化出逃避D. discoideum捕食享有选择性优势，并且这些抗性机制中的许多与细菌用于逃避哺乳动物先天免疫防御的机制相似。本项目验证了对D. discoideum捕食后，这些耐药机制的发展可能有助于巧合的进化细菌的毒力因子对哺乳动物宿主。因此，研究细菌逃避D. discoideum捕食可能导致鉴定新的细菌毒力因子和杀死细菌所需的宿主因子，这些因子一旦被鉴定就可以用作开发抗菌疗法的靶点。新一代测序技术的应用为D. discoideum及其细菌猎物。本奖学金申请旨在支持斯奈德博士在马里兰州大学基因组科学研究所Rasko博士实验室的休假，以便将斯奈德博士对D. discoideum/细菌相互作用的基因组和转录组学方法，其中博士Rasko具有广泛的专业知识。该项目的具体目标是：1）分析已经进化出对D. discoideum捕食作用的转录组学反应; discoideum细胞和细菌猎物的情况下，其中细菌已经和没有进化的抵抗杀死D。盘状体吞噬作用这些研究将告知研究人员宿主-病原体相互作用的分子机制，并应导致对细菌毒力因子的进化和维持以及逃避吞噬过程的机制的深入了解。该项目的完成还将建立斯奈德博士和Rasko博士实验室之间的合作，并将为斯奈德博士提供培训，使她能够开发项目，使本科生和硕士研究生在她的研究实验室和Towson大学的真实研究型实验室课程中进行基因组学研究。

 DESCRIPTION (provided by applicant): Mammalian innate immune cells take up and kill invading bacteria via phagocytosis; however, pathogenic bacterial strains have evolved means to evade killing upon phagocytic uptake to escape innate immune defense. The soil amoeba Dictyostelium discoideum also uses phagocytosis to take up bacteria for nutritive purposes. Bacteria in the soil that have evolved mechanisms to evade D. discoideum predation enjoy a selective advantage, and many of these resistance mechanisms are similar to those used by bacteria to evade mammalian innate immune defense. This project tests the hypothesis that the selective advantage gained against D. discoideum predation upon development of these resistance mechanisms may have contributed to coincidental evolution of bacterial virulence factors against mammalian hosts. Therefore, investigation of bacterial mechanisms used to evade D. discoideum predation could lead to identification of novel bacterial virulence factors and host factors required for bacterial killing, which once identified can be used as targets for development of anti-bacterial therapies. The use of next generation sequencing technology provides a powerful tool for genomic and transcriptomic analyses of the interactions between D. discoideum and its bacterial prey. This fellowship application seeks to support a sabbatical for Dr. Snyder in the laboratory of Dr. Rasko at the University of Maryland Institute for Genome Sciences in order to incorporate into Dr. Snyder's studies of D. discoideum/bacterial interactions genomic and transcriptomic approaches, for which Dr. Rasko has extensive expertise. The specific aims of the project are to 1) analyze the genomes of bacterial strains that have evolved resistance to D. discoideum predation and 2) compare the transcriptomic responses of D. discoideum cells and bacterial prey both in cases in which the bacteria have and have not evolved resistance to killing upon D. discoideum phagocytosis. These studies will inform the investigators on the molecular mechanisms underlying host-pathogen interactions and should lead to insight on the evolution and maintenance of bacterial virulence factors and mechanisms to evade the phagocytic process. Completion of this project will also establish collaborations between the laboratories of Dr. Snyder and Dr. Rasko and will provide Dr. Snyder training so that she can develop projects that will expose undergraduate and masters-level graduate students to genomics research both in her research laboratory and in authentic research-based laboratory courses at Towson University.