Biochemical and Functional Analysis of Trypanin

摘要 非洲锥虫(例如布氏锥虫)是导致非洲人睡眠的原生动物寄生虫 疾病是一种致命的疾病，具有毁灭性的健康和经济影响。这些寄生虫是双基因的。 生物体，它们的部分生命周期在哺乳动物宿主中度过，部分在昆虫媒介(采采蝇)中度过。 锥虫在生命周期的两个阶段都有很高的运动性，运动性是寄生虫发育和 疾病发病机制。运动性是由单个鞭毛介导的，鞭毛是一种基本的多功能 细胞器在细胞运动、寄主-寄生虫相互作用、细胞形态发生和细胞分裂中起关键作用。 令人惊讶的是，我们对分子水平上的鞭毛器知之甚少。特别是，我们缺乏一个 了解鞭毛蛋白如何组装成轴丝内的超分子结构和 它们如何单独和共同作用来驱动细胞运动和其他鞭毛功能。长期的 拟议研究的目的是增进我们对锥虫鞭毛的了解，并利用 以锥虫为模型研究真核纤毛。这将使用以下组合来完成 功能和结构方法。将使用RNAi、定点突变和超微结构分析 目的：研究锥虫蛋白和动力蛋白调节复合体(DRC)的其他成分的功能。刚果民主共和国 是调节鞭毛运动的信号转导通路的一部分，在血流形态中是必不可少的 锥虫，使其成为候选药物靶标。 锥虫的鞭毛类似于包括人类在内的其他真核生物中的纤毛和鞭毛。鞭毛 是几种人类病原体运动所必需的，存在于人体的大多数组织中。他们 执行运动、运输和感觉功能。由需要纤毛的病原体引起的传染病 包括非洲昏睡病和疟疾。这些疾病加在一起会导致死亡和 全世界约有4亿人的发病率。纤毛缺陷引起的人类遗传性疾病 包括：脑积水、不孕症、癫痫、左右轴缺陷、眼疾、多囊肾病和 肥胖。因此，除了解决细胞生物学中的基本问题外，这项研究还直接 影响了解和治疗人类传染病和遗传病的努力。

ABSTRACT African trypanosomes (e.g. Trypanosoma brucei) are protozoan parasites that cause African sleeping sickness, a fatal disease with devastating health and economic impact. These parasites are digenetic organisms, spending part of their life cycle in a mammalian host and part in an insect vector (the tsetse fly). Trypanosomes are highly motile in both life cycle stages and motility is central to parasite development and disease pathogenesis. Motility is mediated by a single flagellum that is an essential and multifunctional organelle with critical roles in cell motility, host-parasite interaction, cell morphogenesis and cell division. Surprisingly, we know very little about the flagellar apparatus at the molecular level. In particular, we lack an understanding of how flagellar proteins are assembled into supramolecular structures within the axoneme and how they function individually and collectively to drive cell motility and other flagellum functions. The long-term goal of the proposed research is to advance our understanding of the trypanosome flagellum and to exploit trypanosomes as a model to investigate the eukaryotic cilium. This will be done using a combination of functional and structural approaches. RNAi, site-directed mutagenesis and ultrastructural analyses will be used to investigate the function of trypanin and other components of the dynein regulatory complex (DRC). The DRC is part of a signal transduction pathway that regulates flagellar motility and is essential in bloodstream-form trypanosomes, making it a candidate drug target. The trypanosome flagellum is analogous to cilia and flagella in other eukaryotes, including humans. Flagella are required for motility of several human pathogens and are present on most tissues of the human body. They perform motility, transport and sensory functions. Infectious diseases caused by pathogens that require cilia include African sleeping sickness and Malaria. Together, these diseases are responsible for mortality and morbidity in approximately 0.4 billion people world-wide. Heritable human diseases caused by cilia defects include: hydrocephalus, infertility, epilepsy, left-right axis defects, eye disorders, polycystic kidney disease and obesity. Therefore, in addition to addressing fundamental questions in cell biology, this research directly impacts efforts to understand and treat infectious diseases and genetic diseases in humans.