Discovery of chemically validated malaria liver stage targets

 描述（由申请方提供）：咪唑并哌嗪类药物（IZPs）是一种新型抗疟药物，正在临床开发中，用于治疗无并发症疟疾和预防疟疾。IZPs消除血液阶段感染，并在疟疾动物模型中预防无症状疟疾发展和疟疾传播。该类中的一个成员已在早期临床试验中进行了测试，口服给药时人体耐受性良好。尽管寄生虫对IZP的耐药性是由编码寄生虫恶性疟原虫环胺耐药位点（PfCARL）的恶性疟原虫基因突变赋予的，但IZP的作用机制尚不清楚。因此，需要进一步研究IZPs如何工作，我们建议使用一套基因组学方法，包括代谢组学，转录组学和其他全基因组方法来研究IZPs如何对抗寄生于人类的所有疟原虫生命周期形式，以确定其精确的靶标。具体来说，我们将首先使用代谢组学分析来研究寄生虫代谢途径如何在血液阶段对寄生虫IZP治疗作出反应。然后，我们将比较这些代谢反应的IZPs的转录响应IZP治疗的血液阶段，肝脏阶段和配子体。我们还将对具有已知作用机制的化合物进行类似的分析，以确定IZP的特异性作用。第二，我们将使用完善的体外进化实验管道，然后进行全基因组测序来探测任何其他靶点。具有确定的耐药突变的基因将与通过代谢组学和转录谱确定的途径相关，以确定推定的靶标。最后，我们将通过一系列的功能研究来确认恶性疟原虫中任何假定的靶点。

 DESCRIPTION (provided by applicant): Imidazolopiperazines (IZPs) are a novel class of antimalarial drug in clinical development for the treatment of uncomplicated malaria and malaria prophylaxis. IZPs eliminate blood stage infections and both prevent asymptomatic malaria development and malaria transmission in animal models of malaria. One member of the class has been tested in early clinical trials and is well-tolerated by humans when administered orally. Although parasite resistance to IZPs is conferred by mutations in the Plasmodium falciparum gene encoding the parasite P. falciparum cyclic amine resistance locus (PfCARL), the mechanism of action of the IZP's is not well understood. Further studies on how the IZPs work are therefore needed, We propose to use a suite of genomic methods including metabolomics, transcriptomics and other genome-wide methods to study how IZPs act against all Plasmodium lifecycle forms that parasitize humans, with the goal of identifying their precise target. Specifically, we will first use metabolomics profiling to examine how parasite metabolic pathways respond to parasite IZP treatment in blood stages. We will then compare these metabolic responses to the IZPs to the transcriptional response to IZP treatment in blood stages, liver stages and gametocytes. We will also perform similar analyses against compounds with known mechanisms of action, in order to identify IZP specific effects. Second, we will probe for any additional targets using a well-established experimental pipeline of in vitro evolution followed by whole genome sequencing. Genes with identified resistance mutations will be associated with the pathways identified by metabolomic and transcriptional profiling to identify putative targets. Finally, we will confirm any putative targets in P. falciparum through a series o functional studies.