PfVP1, a battery of the malaria parasite, is critical for ring stage development

项目摘要 疟疾仍然是一个主要的全球卫生问题，控制进展已经遇到了严重的 近几年的瓶颈问题。每年有超过30亿人生活在感染的风险中 疟疾，2亿人被感染，50万人死于疟疾。作为疟疾 寄生虫对可用的抗疟疾药物迅速产生抗药性，更好地了解 迫切需要基础生物学。在无性血液阶段，疟疾寄生虫主要是 回答糖酵解以获取能量，因为寄生虫的线粒体不进行氧化 磷酸化以产生三磷酸腺苷。它们还含有膜结合的质子泵浦。 焦磷酸酶(MPPase)，它利用200多个细胞的副产物焦磷酸盐 化学反应，作为将质子泵过膜的能量来源。我们之前已经 PfVP2(Pf3D7_1235200)敲除，而PfVP1(Pf3D7_1456800)已被预测 是必不可少的。使用CRISPR/Cas9介导的遗传标签/条件敲除，我们 已发现PfVP1定位于寄生虫的质膜，对环是必需的 阶段性发展。在这个应用中，我们假设PfVP1使用焦磷酸盐作为 在环形阶段维持质子电化学梯度的替代能源 恶性疟原虫的发育。我们将在以下目标中检验这一假设。 目的1、评价PfVP1作为整膜质子泵焦磷酸酶的活性。 目的2，明确PfVP1在环期寄生虫中的功能。总之，这项提案将揭示 环阶段发育和生物能量学的重要见解，关键但研究不足 寄生虫生物学的各个方面。如果成功，这里提出的研究将提供直接的证据 替代能源对疟疾寄生虫的早期发展至关重要 红细胞。在环阶段找到关键的分子靶点也将有助于靶向药物的开发 未来开发更好地抑制新陈代谢不太活跃的寄生虫形式 对当前的抗疟疾药物有抵抗力。

Project Summary Malaria remains a major global health concern and the control progress has run into a serious bottleneck in recent years. Each year, more than 3 billion people are living at risk of contracting malaria, 200 million people are infected and half a million people die from malaria. As malaria parasites rapidly develop resistance to available antimalarial drugs, a better understanding of fundamental biology is urgently needed. In the asexual blood stages, malaria parasites mainly reply on glycolysis for energy since the parasite's mitochondrion does not perform oxidative phosphorylation to produce ATP. They also contain membrane bound proton pumping pyrophosphatases (mPPases), which use pyrophosphate, the by-product of over 200 cellular reactions, as the energy source to pump protons across a membrane. We have previously knocked out PfVP2 (PF3D7_1235200) whereas PfVP1 (PF3D7_1456800) has been predicted to be essential. Using a CRISPR/Cas9 mediated genetic tagging/conditional knockdown, we have found that PfVP1 is localized to the parasite plasma membrane and is essential for ring stage development. In this application, we hypothesize that PfVP1 uses pyrophosphate as an alternative energy source to sustain a proton electrochemical gradient in the ring stage development of Plasmodium falciparum. We will test this hypothesis in the following aims. Aim 1, Assess the activity of PfVP1 as an integral membrane proton-pumping pyrophosphatase. Aim 2, Define the function of PfVP1 in ring stage parasites. Together, this proposal will uncover important insights of ring stage development and bioenergetics, critical yet understudied aspects of parasite biology. If successful, the studies proposed here will provide direct evidence that an alternative energy source is critical for early stage development of a malaria parasite in RBCs. Finding a critical molecular target at the ring stage will also facilitate target-based drug development in future to better inhibit metabolically less active parasite forms that are often resistant to current antimalarials.