Structure Elucidation and Characterization of the Venus Kinase Receptors of a Philippine Isolate of Schistosoma japonicum

在世界范围内，数百万人患有称为血吸虫病的寄生虫病。这种疾病是由血吸虫属的复殖吸虫引起的。这种疾病在菲律宾流行。血吸虫病是一种寄生虫病，由血液寄生蠕虫引起。这种疾病是由感染了人类感染阶段的寄生虫（称为寄生虫尾蚴）的淡水蜗牛传播的。这种疾病的特点是发病率，如肝脏和脾脏的炎症。血吸虫病是菲律宾的地方病。由于其发病率，每年的经济损失达数百万菲律宾比索。250万人有活动性感染，使1 200万人面临感染风险。在菲律宾，S。日本血吸虫是血吸虫病的唯一病原体。该疾病在12个地区，相当于28个省广泛流行。菲律宾的血吸虫病控制计划包括大规模药物管理。在疾病流行率高的地方，用一种药物吡喹酮治疗。每年或每半年给予一次单剂量。然而，对药物的抗药性造成了合理的恐惧。在实验室条件下，S.用亚治疗药物浓度处理的曼氏蠕虫对吡喹酮产生了耐药性。此外，在塞内加尔（1988年），大规模使用吡喹酮未能达到预期的70- 90%的寄生虫治愈率。疾病病理是由沉积在人类宿主不同器官中的寄生虫卵引起的。血吸虫卵是血吸虫病的病原体。因此，对产蛋量进行干预可能会减少疾病负担和控制传播。近年来，在沙门氏菌中发现了Venus激酶受体（VKRs）。曼索尼为血吸虫病研究开辟了新的方向。已经发现VKRs直接参与鸡蛋生产。因此，VKR蛋白的抑制作用可用于开发抗血吸虫病的治疗药物。为了开发新的抗血吸虫蠕虫，需要对VKR蛋白进行分子理解。该提案旨在通过采用蛋白质组学、药物设计和膜蛋白晶体学领域的尖端科学和技术来承担这一复杂的任务。我们将在大肠杆菌中表达和纯化重组形式的VKR蛋白。coli、S. ceriodiae或杆状病毒表达系统。我们将采用实验和计算的方法来charcapillary VKR蛋白质的二聚化潜力，配体结合，抑制剂的相互作用。对VKR抑制剂开发重要的是VKR蛋白的高分辨率结构。我们将尝试结晶VKR蛋白质与和不与他们假定的连接体和抑制剂。VKR结构将用于筛选小分子VKR抑制剂，并将测试与VKR蛋白的结合和磷酸化酶活性。抗血吸虫病药物开发的影响需要数年时间才能交付给最终用户。但是，这一提议是实现这一目标的一个巨大飞跃。研究成果的直接受益者将是学术团体，使他们能够访问VKR蛋白质3D结构的免费数据。有了VKR坐标，将有助于在全世界同时开展抗血吸虫病药物的开发工作。研究中发现的铅化合物可以被制药公司利用，以加快对血吸虫病患者的影响。

Worldwide, millions of people suffer from the parasitic disease called schistosomiasis. This disease is caused by the digenetic trematode of the genus Schistosoma. The disease is endemic in the Philippines. Schistosomiasis is a parasitic disease caused by blood dwelling worms. This disease is spread by freshwater snails infected with the human infective stage of the parasite called schistosome cercariae. The disease is characterized by morbidities like inflammation of the liver and the spleen. Schistosomiasis is endemic in the Philippines. Due to its morbidities, economic loss amount to millions of Philippine Peso per year. Two and a half million people have active infections, posing 12 million individuals at risk of infection. In the Philippines, S. japonicum is the only causative agent of schistosomiasis. The disease is widespread in 12 Regions, corresponding to 28 Provinces. Schistosomiasis control program in the Philippines include mass drug administration. Endemic places with high disease prevalence rates are treated with a single drug, praziquantel. A single dose is given once annually or biannually. However, resistance to the drug poses legitimate fear. Under laboratory conditions, S. mansoni worms treated with subcurative drug concentration developed resistance against praziquantel. Moreover, in Senegal (1988), mass drug administration of praziquantel failed to meet the expected parasitological cure rate of 70-90%. The disease pathologies are caused by schistosome eggs deposited in different organs in the human host. Schistosome eggs are the causative agents of schistosomiasis. As such, interventions of schistosome egg production may lead to reduction of disease burden and transmission control. In recent years, the discovery of Venus Kinase Receptors (VKRs) in S. mansoni opened new directions in schistosomiasis research. It has been found that VKRs are directly involved in egg production. Thus, inhibition of VKR proteins can be exploited to develop anti-schistosomiasis therapeutics.In order to develop new drugs active against schistosome worms, molecular understanding of VKR proteins will be needed. This proposal aims to undertake this complex task by employing cutting edge science and technology in the field of proteomics, drug design and membrane protein crystallography. We will express and purify the recombinant form of VKR proteins in either E. coli, S. cerivisiae or Bacullovirus expression systems. We will employ both experimental and computational approches to charcaterize VKR proteins in terms of their dimerization potential, ligand binding, and inhibitor interactions. Important to VKR inhibitor development is high resolution structure of VKR proteins. We will attempt to crystallize VKR proteins with and without their putative liagnds and inhibitors. The VKR structure will be used to screen small molecule VKR inhibitors, and will be tested for binding to VKR proteins and phosphorylase activity.The impact of anti-schistosomiasis drug development takes years to deliver to end users. But, this proposal is a huge leap towards its realization. The immediate beneficiaries of study outcomes will be the academic groups, allowing them to access free data of the 3D structure of VKR proteins. With VKR coordinates available, simultaneous work on the development of anti-schistosomiasis drugs worldwide will be facilitated. Lead compounds identified in the study can be exploited by pharmaceutical companies to speed up delivery of impact to suffering individiduals due to schistosomiasis.