Chemical characterization of SUMO specific proteases in Plasmodium falciparum

描述(申请人提供)：疟疾是一种由人类原生动物寄生虫恶性疟原虫引起的疾病，每年影响3亿至5亿人，每年造成约200万人死亡。大多数疾病病理与寄生虫48小时的血液期生命周期有关。在感染的这一阶段，寄生虫使用高度调控的基因表达程序，在几个不同的形态阶段协调过渡。目前，人们对实现这种高水平转录控制的机制知之甚少。由于恶性疟原虫中缺乏规范的真核转录因子，翻译后修饰很可能在寄生虫生命周期的调控中发挥着重要而独特的作用。小泛素相关修饰物(SUMO)是一种蛋白质，被用作翻译后修饰物来改变靶蛋白的功能。苏莫化被认为调节转录、蛋白质定位、蛋白质-蛋白质相互作用和细胞周期。相扑最近在恶性疟原虫中被发现。然而，由于相扑不断地从底物中移除，以及执行这一加工事件的相扑特异性蛋白酶(SENPs)的基本性质，对SUMO化途径的剖析仍然很困难。因此，新的工具可以用来阻断SENPs的活性和高度的时间控制，这将是非常有价值的研究恶性疟原虫的SUMO化。这项提案概述了我们开发小分子工具来干扰恶性疟原虫中SENPs功能的计划。我们假设，SUMO化是寄生虫用来控制寄主内生存所需的关键过程的关键调控机制。因此，这些酶的抑制剂将使我们既可以验证SENPs作为潜在的抗疟疾药物靶点，也可以通过蛋白质组学方法分离相扑修饰蛋白的群体。这些数据将提供有关寄生虫如何使用SUMO化作为一般调控机制的信息。最终，这些试剂将帮助我们深入了解SUMO化的功能意义，并可能导致识别其他可以被干扰的治疗途径。 与公共卫生相关：我们假设SUMO化是专性细胞内寄生虫恶性疟原虫控制宿主内部生存所需的关键过程的关键调控机制。该项目概述了开发小分子蛋白酶抑制剂的计划，这些小分子抑制剂调节相扑从底物蛋白中的去除。这些化合物可以用来剖析SUMO化在寄生虫生命周期中的功能作用。最终，这些信息可能导致治疗疟疾的新治疗策略。

DESCRIPTION (provided by applicant): Malaria, a disease caused by the human protozoan parasite Plasmodium falciparum, affects 300-500 million people annually and is the cause of approximately 2 million deaths per year. The majority of disease pathology is associated with the 48 hour blood stage life cycle of the parasite. During this phase of infection, the parasite uses a highly regulated program of gene expression to orchestrate transition through several morphologically distinct phases. Currently, very little is known about the mechanisms used to achieve this high level of transcriptional control. Due to the absence of canonical eukaryotic transcription factors in P. falciparum, it is likely that post-translational modifications play important and unique roles in the regulation of the parasite life cycle. Small ubiquitin-related modifier (SUMO) is a protein that is used as a posttranslational modifier to alter the function of target proteins. SUMOylation is believed to regulate transcription, protein localization, protein- protein interactions, and the cell cycle. SUMO was recently identified in P. falciparum. Yet it remains difficult to dissect SUMOylation pathways because of the constant removal of SUMO from substrates and the essential nature of the SUMO-specific proteases (SENPs) that carry out this processing event. Thus, new tools that can be used to block the activity of the SENPs with a high degree of temporal control would be highly valuable for the study of SUMOylation in P. falciparum. This proposal outlines our plan to develop small molecule tools to perturb the function of the SENPs in P. falciparum. We hypothesize that SUMOylation is used as a critical regulatory mechanism by the parasite to control key processes necessary for survival inside the host. Therefore, inhibitors of these proteases will allow us to both validate SENPs as potential anti-malarial drug targets and also to isolate populations of SUMO modified proteins by proteomic methods. This data will provide information about how the parasite uses SUMOylation as a general regulatory mechanism. Ultimately, these reagents will help us to gain insight into the functional significance of SUMOylation and may lead to the identification of additional pathways that can be disrupted for therapeutic gain. PUBLIC HEALTH RELEVANCE: We hypothesize that SUMOylation is used as a critical regulatory mechanism by the obligate intracellular parasite Plasmodium falciparum to control key processes necessary for survival inside the host this project outlines plans to develop small molecule inhibitors of the proteases that regulate SUMO removal from substrate proteins. These compounds can be used to dissect the functional role of SUMOylation in the parasite life cycle. Ultimately this information may lead to new therapeutic strategies to treat malaria.