Collaborative Research: How does an intracellular symbiont manipulate host cell biology?

合作研究：细胞内共生体如何操纵宿主细胞生物学？

• 批准号: 1456545
• 负责人: Irene Newton
• 金额: $ 41.4万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1456545&HistoricalAwards=false
• 关键词: Collaborative; Research; How; does; intracellular

Wolbachia pipientis is a bacterium that infects a large number of insects, including important human disease vectors such as mosquitos. This bacterium is maternally transmitted and is known to cause a variety of effects in the insect host including manipulation of reproduction and suppression of virus replication. Because Wolbachia is capable of suppressing virus replication in insect hosts, it is being used to decrease the spread of human diseases (so-called "pathogen blocking"). It is critical, therefore, to better understand how Wolbachia infects hosts and alters host cell biology. Although Wolbachia infect upwards of 40% of insects on the planet, there is surprisingly little known about the exact mechanism used by the bacterium to manipulate its host. This is largely due to the fact that Wolbachia occurs inside host cells and cannot be genetically manipulated presently. This project will use a novel approach in this system to identify proteins used by the bacterium to alter host cell biology. By identifying and characterizing these proteins, much will be learned about the basic biology of Wolbachia and the host cell components utilized during infection. Results will also lead to comparative analyses in other symbiotic systems. Undergraduate students from underrepresented groups in science will be trained with project-based research related to this project on Wolbachia.The overarching scientific goal of this project is to identify the mechanisms by which an extraordinarily widespread bacterium interacts with its host. Wolbachia pipientis is an intracellular alpha-proteobacterium that forms symbioses with an extremely broad array of invertebrates, including isopods, nematodes, and insects. Wolbachia is currently of interest with regards to vector control because mosquitoes harboring the bacterium are unable to transmit important human diseases. Because Wolbachia are not currently culturable or genetically tractable, little is known about the molecular basis of interaction with eukaryotic hosts. Wolbachia encodes a type IV secretion system and is thought to secrete proteins (termed "effectors") into the eukaryotic cell to alter the biology of its insect hosts. This project will use a powerful method to identify and study the biochemical function of probable effectors in Wolbachia. The investigators will identify candidate effectors through genomics and bioinformatics. They will use a yeast genetic screen and a secretion assay in a heterologous system to further identify and characterize these candidates. Finally, the researchers will investigate the biochemical function and cellular effects of these proteins in the Drosophila host. These results will be the first comprehensive analysis of Wolbachia secreted substrates and will lead to significant advances in the Wolbachia field and comparative work in other symbiotic strains (such as those infecting filarial nemotodes).

Wolbachia pipientis是一种细菌，可感染大量昆虫，包括重要的人类疾病媒介，例如蚊子。 该细菌是在母体传播的，已知在昆虫宿主中引起各种作用，包括操纵繁殖和抑制病毒复制。 由于沃尔巴奇能够抑制昆虫宿主中的病毒复制，因此它被用来减少人类疾病的传播（所谓的“病原体阻塞”）。因此，至关重要的是要更好地了解沃尔巴奇如何感染宿主并改变宿主细胞生物学。 尽管Wolbachia在地球上感染了40％以上的昆虫，但令人惊讶的是，对细菌用来操纵其宿主的确切机制鲜为人知。 这很大程度上是由于沃尔巴基亚发生在宿主细胞内，目前不能在遗传上受到操纵。 该项目将使用该系统中的一种新方法来识别细菌用来改变宿主细胞生物学的蛋白质。 通过识别和表征这些蛋白质，将了解有关沃尔巴基亚的基本生物学以及在感染过程中使用的宿主细胞成分的基本生物学。结果还将导致其他共生系统中的比较分析。来自代表性不足的科学群体的本科生将接受与该项目有关的项目研究的基于项目的研究。该项目的总体科学目标是确定与其宿主相互作用的广泛广泛细菌的机制。 Wolbachia pipientis是一种细胞内α-杆菌，形成与极宽的无脊椎动物的共生性，包括等脚架，线虫和昆虫。 Wolbachia目前对媒介控制感兴趣，因为藏有细菌的蚊子无法传播重要的人类疾病。由于沃尔巴奇目前不可培养或遗传障碍，因此对与真核宿主相互作用的分子基础知之甚少。 Wolbachia编码IV型分泌系统，被认为将蛋白质（称为“效应子”）分泌到真核细胞中，以改变其昆虫宿主的生物学。 该项目将使用一种强大的方法来识别和研究沃尔巴基亚可能效应子的生化功能。 研究人员将通过基因组学和生物信息学鉴定候选效应子。 他们将在异源系统中使用酵母遗传筛选和分泌分析，以进一步识别和表征这些候选者。 最后，研究人员将研究这些蛋白质在果蝇宿主中的生化功能和细胞作用。 这些结果将是对Wolbachia分泌底物的首次综合分析，并将导致Wolbachia领域的重大进展以及其他共生菌株（例如那些感染丝状线虫的人）的比较工作。