Molecular mechanisms controlling secretion in filarial nematode parasites

项目摘要 寄生线虫感染了超过15亿人。控制与贫困相关的全球健康负担有赖于 几乎完全依赖于少量驱虫药的管理。驱虫药的发展前景 在许多线虫寄生虫中，这些药物的耐药性和次优性质需要新的方法来治疗 寄生虫的治疗和控制。然而，开发新的抗寄生虫治疗方案的必要性受到阻碍。 由于我们对线虫生物学过程的基本知识存在巨大差距，线虫生物学过程促进了 保持感染。寄生线虫向宿主释放的排泄物-分泌物 环境对寄主的免疫调节和成功的寄生是必不可少的。尽管总体上- 认为ES系统是释放促进寄生虫的分子(蛋白质和囊泡)的管道 生存，我们对ES装置的基本结构和功能在医学上了解很少。 重要的寄生线虫。为了解决这一知识差距，该项目将确定分泌物的调节者 蚊媒fi疟疾线虫和人淋巴管fi大病毒病原体--马来丝虫的功能 IASIS(Lf)。最近对马来丝虫的研究，包括对伊维菌素作用方式的研究，支持这样一个前提 ES装置是新的治疗靶点的有利可图和未被开发的来源。我们最重要的假设 马来杆菌ES系统的细胞表面受体是否直接或间接控制寄生虫的分泌？ 功能，并且它们可以被靶向干扰ES衍生分子的释放。我们将继续追查 三个目标，由初步的受体导联激励，并通过创新的方法使其可行 为了解决马来不动杆菌ES系统的转录状态，并使与寄生虫Se有关的fiLE受体成为可能。 排泄功能。我们把精力集中在G蛋白偶联受体(Gpcr)上，这是prolific药物靶点。 并且已知在线虫ES细胞和可能作用于ES系统的相邻细胞类型中表达。在……里面 目的1，我们将使用创新的空间转录组学方法来解析马来不动杆菌的转录组 跨宿主阶段的ES区域，并识别调节ES功能的候选GPCR。在目标2中，我们将 使用反向遗传学和化学方法评估ES定位的GPCRs在调节 B.Malayi分泌功能。在目标3中，我们将使用全生物线虫模型和哺乳动物单细胞 异源表达平台研究ES-定位GPCRs的药理作用并建立功能性fi GPCR筛查的检测方法。这个项目的完成将产生关于fi拉菌的基本新知识 线虫ES系统，并为新的抗fi疟疾药物发现提供新的领先目标和有效的筛选。

Project Summary Parasitic nematodes infect over 1.5 billion humans. Control of this poverty-associated global health burden relies almost entirely on the administration of a small number of anthelmintic drugs. The prospects of anthelmintic resistance and the sub-optimal nature of these drugs in many nematode parasites demand new approaches to parasite treatment and control. However, the need to develop new antiparasitic treatment options is hampered by large gaps in our basic knowledge of the nematode biological processes that promote the establishment and maintenance of infection. Excretory-secretory (ES) products released by parasitic nematodes into their host environments are essential for host immune modulation and successful parasitism. Despite the general under- standing that the ES system is a conduit for the release of molecules (proteins and vesicles) that promote parasite survival, we have a poor understanding of the underlying structure and function of the ES apparatus in medically important parasitic nematodes. To address this gap in knowledge, this project will identify regulators of secretory function in Brugia malayi, a mosquito-transmitted filarial nematode and causative agent of human lymphatic filar- iasis (LF). Recent studies in B. malayi, including on the mode of action of ivermectin, support the premise that the ES apparatus is a lucrative and unexploited source of new therapeutic targets. Our overarching hypothesis is that cell-surface receptors localized to the B. malayi ES system directly or indirectly control parasite secretory function, and that they can be targeted to interfere with the release of ES-derived molecules. We will pursue three aims, motivated by preliminary receptor leads and made feasible by innovative methods we have optimized to resolve the transcriptomic state of the B.malayi ES system and to profile receptors implicated in parasite se- cretory function. We focus our efforts on G protein-coupled receptors (GPCRs), which are prolific drug targets and known to be expressed in nematode ES cells and adjacent cell types that may act on the ES system. In Aim 1, we will use innovative spatial transcriptomics approaches to resolve the transcriptome of the B. malayi ES region across intra-host stages and to identify candidate GPCRs that regulate ES function. In Aim 2, we will use reverse genetics and chemical approaches to assess the role of ES-localized GPCRs in the regulation of B. malayi secretory function. In Aim 3, we will use whole-organism model nematode and mammalian single-cell heterologous expression platforms to define the pharmacology of ES-localized GPCRs and to establish functional assays for GPCR screening. Completion of this project will produce fundamental new knowledge about the filarial nematode ES system and deliver new lead targets and validated screens for novel anti-filarial drug discovery.