Heat Shock Protein Prenylation in Malaria Parasites

项目摘要/摘要 疟疾是全球人类死亡的一个重要因素，估计造成44.5万人死亡和 每年2.16亿例。绝大多数疟疾死亡是由恶性疟原虫感染引起的。 对现有抗疟疾药物的耐药性继续出现，包括目前使用的青蒿素类药物 综合疗法。迫切需要治疗疟疾的新的治疗目标，并以目标为基础 药物开发依赖于我们对基本寄生虫生物学的基本理解。恶性疟原虫需要 蛋白质预烯化，蛋白质的C末端翻译后的脂质修饰，用于无性复制。我们的 长期目标是揭示疟疾寄生虫为什么需要预烯基化才能生存的分子基础。 我们最近确定了血液期恶性疟原虫的完整的前烯基化蛋白质组。我们的 初步研究表明，热休克蛋白PfHsp40(PF3D7_1437900)是一种强健的前烯基化蛋白。热度 休克蛋白是蛋白质折叠和稳定所必需的，其表达在 不同的细胞压力，包括热休克。恶性疟原虫在其整个生命周期中都会经历热休克和 因此，大约2%的恶性疟原虫基因组专门用于分子伴侣就不足为奇了。 作为热休克蛋白。这项建议的目的是确定PfHsp40的生物学作用和调节。 拟议的研究将回答几个基本问题，包括：PfHsp40在P。 恶性疟原虫？苯丙基化是否影响PfHsp40在寄生虫中的作用？强劲的初步数据支持 这预示着这一战略将是成功的，目标将通过两个具体目标来实现：1)确定 PfHsp40在恶性疟原虫无性复制中的重要性；以及2)决定恶性疟原虫 蛋白质预烯基化控制着PfHsp40的生物学作用。这种方法是创新的，因为它使用 结合最先进的遗传操作系统直接建立蛋白质的功能方面 疟原虫中的戊烯基化。这项拟议的研究意义重大，因为它将阐明PfHsp40的作用 在寄生虫中，确定预烯基化如何影响PfHsp40的生物学作用，并确定下游 寄生虫中需要戊烯基化的蛋白质和途径。此外，因为热休克蛋白是 在整个分类群中发现的这些发现可能会揭示关于热休克蛋白功能的广泛适用的概念。

PROJECT SUMMARY/ABSTRACT Malaria is a significant contributor to global human mortality and accounts for an estimated 445,000 deaths and 216 million cases per year. The vast majority of malaria deaths result from Plasmodium falciparum infection. Resistance to available antimalarials continues to emerge including currently used artemisinin-based combination therapies. New therapeutic targets for treatment of malaria are greatly needed, and target-based drug development relies on our fundamental understanding of essential parasite biology. P. falciparum requires protein prenylation, the C-terminal post-translational lipid modification of proteins, for asexual replication. Our long term goal is to uncover the molecular basis of why prenylation is required by the malaria parasite for survival. We recently identified the complete prenylated proteome of blood-stage P. falciparum malaria parasites. Our preliminary studies revealed that PfHsp40 (PF3D7_1437900), a heat shock protein, is robustly prenylated. Heat shock proteins are necessary for protein folding and stabilization and their expression is upregulated under different cellular stresses including heat shock. P. falciparum experiences heat shock throughout its lifecycle and it is not surprising then that roughly 2% of the P. falciparum genome is dedicated to molecular chaperones such as heat shock proteins. The objective of this proposal is to establish the biological role and regulation of PfHsp40. The proposed studies will answer several fundamental questions including: What is the role of PfHsp40 in P. falciparum? Does prenylation influence the role of PfHsp40 in the parasite? Supported by strong preliminary data that indicate that this strategy will be successful, the objective will be met through two specific aims: 1) Determine the importance of PfHsp40 in asexual replication of P. falciparum; and 2) Determine the mechanism by which protein prenylation controls the biological role of PfHsp40. This approach is innovative, since it uses a combination of state-of-the-art genetic manipulation systems to directly establish the functional aspects of protein prenylation in Plasmodium. The proposed research is significant, because it will illuminate the role of PfHsp40 in the parasite, establish how prenylation influences the biological role of PfHsp40, and identify downstream proteins and pathways that require prenylation in the parasite. Furthermore, because heat shock proteins are found across taxa, the findings are likely to reveal broadly applicable concepts about heat shock protein function.