Trypanosome transmembrane kinases

描述(申请人提供)：原生动物寄生虫布鲁氏锥虫亚种是非洲昏睡病的病原体，这种疾病在不治疗的情况下总是致命的。布鲁氏锥虫已经成为研究相关锥虫病原体克氏锥虫和利什曼原虫的模式系统，这三种病原体总共感染了全世界超过1200万人。疫苗的缺乏和对抗昏睡病的药物的毒性使得研究新的药物靶点变得势在必行。随着这三种锥虫基因组序列的公布，现在有了许多候选目标中的哪一个来追求的重要决定。蛋白激酶是一大类酶，在癌症和其他疾病中充当药物靶点。它们感知细胞外或细胞内环境，调节许多细胞反应，包括细胞分裂、对压力、发育和死亡的反应。该项目建议使用条件性基因敲除和化学遗传方法来研究可能在宿主-寄生虫相互作用中发挥作用的蛋白激酶的作用。我们已经优先考虑了两种新的蛋白激酶，它们位于 在鞭毛和鞭毛袋处有布氏毛滴虫的膜。寄生虫的这一区域在细胞运动和分裂、营养获取和免疫逃避机制中发挥着重要作用。令人惊讶的是，与其他真核蛋白激酶不同的是，这些蛋白激酶具有多个跨膜结构域，意味着新的信息偶联模式。我们的RNAi研究表明，它们在致病血流阶段很重要，它们在寄生虫中的位置预测了它们在宿主-寄生虫相互作用中的重要作用。在体外和小鼠模型中，有条件地敲打这些激酶将牢固地确立这些激酶的作用。使用突变形式的激酶的化学遗传学方法将被用来确定特定的药物抑制是否导致与缺乏蛋白质相同的表型，最终评估这些蛋白激酶作为药物靶标的适宜性，并提供机会剖析这些激酶的功能途径。

DESCRIPTION (provided by applicant): The protozoan parasite Trypanosoma brucei subspecies are the causative agent of African sleeping sickness, a disease that is invariably fatal without treatment. T. brucei has served as a model system for the study of the related trypanosomatid pathogens Trypanosoma cruzi and Leishmania spp., and the three together infect over 12 million people worldwide. The absence of vaccines and the toxic nature of drugs that combat sleeping sickness make research into new drug targets imperative. With the release of the genome sequences of these three trypanosomatids, there are now important decisions as to which of many candidate targets to pursue. Protein kinases are a large class of enzymes that serve as drug targets in cancer and other diseases. They sense the extracellular or intracellular environment and regulate numerous cellular responses, including cell division, responses to stress, development, and death. This project proposes the use of conditional knockout and chemical genetic approaches to examine the roles of protein kinases likely to play a role in host-parasite interactions. We have prioritized two novel protein kinases that reside in T. brucei membranes at the flagellum and flagellar pocket. This region of the parasite plays a prominent role in cell motility and division, nutrient acquisition, and immune evasion mechanisms. Surprisingly, unlike other eukaryotic protein kinases, these kinases possess multiple membrane spanning domains, implying novel modes of information coupling. Our RNAi studies indicate that they are important in the pathogenic bloodstream stage and their location within the parasite predicts a significant role in host-parasite interactions. Conditional knockous of the kinases will firmly establish the role of the kinases in vitro and in a mouse model. A chemical genetic approach using mutant forms of the kinases will be pursued to determine whether specific drug inhibition causes the same phenotypes as absence of the protein, conclusively assessing the suitability of these protein kinases as drug targets and providing the opportunity to dissect the pathways in which the kinases function.