Biochemical and Functional Analysis of Trypanin

描述(申请人提供)：有鞭毛的原生动物寄生虫布鲁氏锥虫是非洲锥虫病的罪魁祸首，这种疾病在撒哈拉以南非洲造成广泛的人畜死亡和发病。昏睡病如果不治疗是致命的，但目前还没有疫苗存在，而且目前的治疗方法陈旧、有毒且难以管理。因此，迫切需要研究更好地了解这些寄生虫，并促进新的治疗干预措施的开发。锥虫也是研究鞭毛和纤毛生物学的重要实验系统，而鞭毛和纤毛对正常人类健康至关重要。布氏毛滴虫依靠其鞭毛在宿主组织内运动，并指导细胞的发育和分裂。在广泛的真核生物中的广泛研究表明，除了鞭毛在运动中的典型作用外，它还作为一个信号中心来感知和响应环境中的外部提示。最近的研究表明，锥虫鞭毛同样具有运动性和信号传递能力。这项拟议工作的长期目标是确定运动性在发病中的作用，确定调节锥虫运动性的机制，并检验鞭毛指导毒力重要信号系统的假设。为了做到这一点，我们将使用运动性突变体，小鼠感染模型来测试信号和运动性功能对感染的贡献。我们还将使用系统生物学方法来定义鞭毛中的信号系统，并识别由这些信号系统控制的基因。最后，我们将使用冷冻电子断层扫描结合突变分析来建立鞭毛的三维分子模型，以努力了解锥虫体内独特鞭毛功能的结构基础。我们的重点是布氏毛滴虫的鞭毛。然而，鞭毛对许多其他致病原虫以及正常的人类发育和健康都是重要的。因此，我们预计我们的结果将对研究寄生原虫的发病机制、人类发育和生理以及真核生物的基础生物学的社区产生广泛的兴趣。

DESCRIPTION (provided by applicant): The flagellated protozoan parasite Trypanosoma brucei is responsible for African trypanosomiasis, which causes widespread mortality and morbidity of humans and livestock in sub-Saharan Africa. Sleeping sickness is fatal if untreated, yet no vaccine exists and current treatments are old, toxic and difficult to administer. Thus, ther is a pressing need for research to better understand these parasites and facilitate development of new therapeutic interventions. Trypanosomes are also an important experimental system for studying biology of flagella and cilia, which are critical to normal human health. T. brucei depends on its flagellum for movement within host tissues and for directing cell development and division. Extensive work in a wide range of eukaryotes demonstrates that in addition to the flagellum's canonical role in motility, it functions as a signaling center to perceive and respond o external cues in the environment. Recent work indicates that the trypanosome flagellum likewise functions in motility and signaling capacity. The long term goal of the proposed work is to determine the role of motility in pathogenesis, define mechanisms that regulate trypanosome motility and test the hypothesis that the flagellum directs signaling systems important for virulence. To do this, we will employ motility mutants, mouse infection models to test signaling and motility functions for a contribution to infection. We will also employ systems biology approaches to define signaling systems in the flagellum and identify genes controlled by these signaling systems. Finally, we will use cryoelectron tomography, together with mutational analysis to build a three-dimensional molecular model of the flagellum in an effort to understand structural foundations of unique flagellum functions in trypanosomes. Our focus is on the flagellum of T. brucei. However, flagella are important for many other pathogenic protozoa as well as for normal human development and health. Therefore, we expect our results to be of wide interest for the community studying pathogenesis of parasitic protozoa, human development and physiology, and fundamental biology of eukaryotes.