Defining the targets of broad intervention antimalarial agents

确定广泛干预抗疟药物的目标

基本信息

批准号：
9109547
负责人：
Elizabeth A Winzeler
金额：
$ 63.65万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-08-14 至 2019-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9109547
关键词：
Address Anopheles Genus Antimalarials Artemisinins Binding Sites Biochemical Bioinformatics Biological Biological Assay Biology Blood Body Weight Cell Death Cellular Assay Chemical Evolution Chemicals Chemoprophylaxis Combined Modality Therapy Communities Copy Number Polymorphism Data Development Drug resistance Drug-sensitive Evolution Failure Family Gene Exchanges Genes Genetic Genetic Engineering Genome Genomic approach Genomics Health Hepatic Human In Vitro Infection Intervention Knock-out Libraries Liver Malaria Mediating Medicine Methods Mission Mitochondria Molecular Multi-Drug Resistance Mutation Nucleic Acids Parasites Pattern Pharmaceutical Preparations Physiology Plasmodium Plasmodium falciparum Plasmodium vivax Primaquine Probability Property Protein Biosynthesis Proteins Reading Recombinants Research Research Proposals Resistance Risk Role Series Single Nucleotide Polymorphism Speed Staging Testing Toxic effect Transfection Validation Work acquired drug resistance antimicrobial drug artemisinine asexual base curative treatments drug candidate drug development drug discovery genome sequencing inhibitor/antagonist innovation member mutant next generation next generation sequencing novel parasite genome pathogen pressure prevent public-private partnership research study resistance mechanism resistant strain scaffold screening small molecule transmission process vector mosquito whole genome zinc finger nuclease

项目摘要

DESCRIPTION (provided by applicant): Although phenotypic cellular screening has recently been used to drive antimalarial drug discovery, there continues to be a clear need for rational target-based drug discovery. This is especially true when appropriate high-throughput cellular assays are lacking. Such is the case for drug discovery efforts that aim to provide a replacement for primaquine, a drug with known toxicity that is the only agent that eliminates Plasmodium vivax liver stage infection and blocks gametocyte transmission. At present, there are no known chemically validated parasite protein targets that are critical to replicating or hypnozoite liver stages as well as asexual blood and gametocyte stages, and that could be used in biochemical screens of large compound libraries. The genomes of Plasmodium parasite species encode over 5,500 proteins, many of which remain uncharacterized. Our central hypothesis is that a wealth of novel, chemically validated multi-stage antimalarial targets still remain to be discovered. To test this we propose to focus on five recently discovered, chemically distinct scaffolds with broad ranging activity against the parasite lifecycle, including liver and asexual blood stages. We will further prioritize compounds by determining which of these are active against P. falciparum asexual blood stages from multidrug-resistant strains, gametocytes, and P. vivax hepatic forms. To generate low-level resistance, we will expose P. falciparum parasites (three independent selections, against three members of each scaffold series) to sublethal concentrations of compound. The genomes of drug-resistant clones will be examined by next-generation sequencing with paired-end reads (yielding ~100X coverage) to identify the complete suite of genetic changes that have emerged in each clone during chemical selection. Based on our preliminary data, we expect to find a statistically significant enrichment of newly emerged mutations in only one gene for each scaffold, when considering the whole-genome sequence for all nine resistant strains created per scaffold family. The importance of the candidate targets wil be verified by introducing genetic changes into drug-sensitive P. falciparum parasites and testing for gain of resistance, or conversely removing candidate mutations and testing for loss of resistance. Transfection experiments will include zinc finger nucleases, which constitute a major breakthrough in their ability to mediate highly efficient gene editing in P. falciparum. We will alo seek to determine whether the identified gene is the target of the small molecule or a gene involved in resistance through a detailed molecular characterization. The work will provide the malaria community with a systematic picture of how P. falciparum acquires drug resistance, and is expected to yield several new validated targets that can be used in drug development efforts focused on finding new radical-cure agents. This research, which is consistent with NIAID's mission statement, promises to leverage chemical scaffolds active against Plasmodium parasites to define new targets for the development of broad intervention strategies based on chemoprophylaxis and curative treatment of malarial infections.

描述（由申请人提供）：尽管最近已使用表型细胞筛选来驱动抗疟药发现，但仍然需要显然需要基于靶向靶向的药物发现。当缺乏适当的高通量细胞测定时，尤其如此。药物发现工作就是这种情况，旨在替代Primaquine，这是一种已知毒性的药物，是唯一消除了Vivax肝脏肝脏阶段感染并阻止配子细胞传播的药物。目前，尚无已知的化学验证寄生虫蛋白靶标，对于复制或催眠症肝阶段以及无性血液和配子细胞阶段至关重要，并且可以用于大型化合物文库的生化筛选中。疟原虫种类的基因组编码超过5500种蛋白质，其中许多蛋白质仍然没有表征。我们的中心假设是，仍然有许多新颖，化学验证的多阶段抗疟药靶标仍然有待发现。为了测试这一点，我们建议将重点放在最近发现的五个化学上不同的支架上，具有针对寄生虫生命周期的范围广泛的活性，包括肝脏和无性血液阶段。我们将通过确定其中哪种对恶性疟原虫的无性血液阶段的活性来进一步优先考虑化合物，从多药抗性菌株，配子细胞和Vivax肝肝形式。为了产生低水平的电阻，我们将暴露于恶性疟原虫（三个独立的选择，针对每个脚手架系列的三个成员）中的化合物浓度。通过配对末端读数（产生〜100倍覆盖范围）的下一代测序将检查耐药克隆的基因组，以鉴定化学选择过程中每个克隆中出现的完整遗传变化套件。根据我们的初步数据，我们希望在每个支架上考虑每个脚手架菌株的全基因组序列时，只有一个基因中的一个基因中的新出现的突变具有统计学上显着的突变。候选目标的重要性将通过将遗传变化引入对药物敏感的恶性疟原虫寄生虫并获得抗药性的测试，或者相反消除候选突变并测试耐药性丧失，来验证。转染实验将包括锌指核酸酶，这构成了它们介导恶性疟原虫中高效基因编辑的能力的重大突破。我们将寻求确定鉴定的基因是通过详细的分子表征与抗性相关的基因的靶标。这项工作将为疟疾社区提供有关恶性疟原虫如何获得耐药性的系统图片，并有望产生几个新的有验证的靶标，这些靶标可用于药物开发工作，以寻找新的激进储备药物。这项与NIAID的使命陈述相一致的这项研究有望利用活跃于疟原虫的化学支架来定义基于化学预防的广泛干预策略的新靶标，并治疗疟疾感染。

项目成果

期刊论文数量（6）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

A high susceptibility to redox imbalance of the transmissible stages of Plasmodium falciparum revealed with a luciferase-based mature gametocyte assay.

DOI：
10.1111/mmi.13626
发表时间：
2017-04
期刊：
Molecular microbiology
影响因子：
3.6
作者：
Siciliano G;Santha Kumar TR;Bona R;Camarda G;Calabretta MM;Cevenini L;Davioud-Charvet E;Becker K;Cara A;Fidock DA;Alano P
通讯作者：
Alano P

Lead optimization of imidazopyrazines: a new class of antimalarial with activity on Plasmodium liver stages.

咪唑并吡嗪的先导化合物优化：一种对疟原虫肝脏阶段具有活性的新型抗疟药。

DOI：
10.1021/ml500244m
发表时间：
2014
期刊：
ACS medicinal chemistry letters
影响因子：
4.2
作者：
Zou,Bin;Nagle,Advait;Chatterjee,ArnabK;Leong,SehYong;Tan,LiyingJocelyn;Sim,WeiLinSandra;Mishra,Pranab;Guntapalli,Prasuna;Tully,DavidC;Lakshminarayana,SureshB;Lim,ChekShik;Tan,YongCheng;Abas,SitiNurdiana;Bodenreider,Chr
通讯作者：
Bodenreider,Chr

Longitudinal study of Plasmodium pathogens identifies new loci associated with artemisinin resistance.