EAGER: Viruses of the Protozoan Parasites Perkinsus spp.: Isolation and Characterization

EAGER：原生动物寄生虫 Perkinsus spp. 的病毒：分离和表征

• 批准号: 1550399
• 负责人: Joaquin Martinez Martinez
• 金额: $ 29.87万
• 依托单位: Bigelow Laboratory for Ocean Sciences
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2018-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1550399&HistoricalAwards=false
• 关键词: EAGER; Viruses; Protozoan; Parasites; Perkinsus

Oysters and clams are often challenged by parasites, including Perkinsus species. Perkinsus spp., causative of Dermo disease, can lead to mass mortalities of farmed and wild bivalve populations and hence have important detrimental ecological and economic consequences. Perkinsus is on the World Organization for Animal Health's list of reportable diseases. Most of the studies aimed to understand and intervene against Dermo have centered in a game of two: parasite and host. However, previous ultrastructural studies have shown the presence of virus-like particles in the nucleus of the parasite. Yet, nothing is known about these viruses' genetics, mechanism of infection, or consequences on Perkinsus ecology. Research on other parasitic protozoa (including some with human hosts) has revealed many interesting biological phenomena that suggest that there is every reason to expect that viruses have a profound effect on the propagation, life style and virulence of Perkinsus spp. Proving viral infection of Perkinsus spp. and understanding the host's functional responses to infections will represent a paradigm shift in our thinking about Perkinsus spp. ecology and virulence toward their bivalve hosts. Furthermore, it will open the door to new approaches for intervention against the disease-causing agent. This project is considered high risk-high payoff since, thus far, compelling evidence of viruses infectious to Perkinsus is based on ultrastructural studies using electron microscopy, but information to assess ease of virus isolation is lacking. This project focuses on isolating and characterizing viruses that infect Perkinsus spp. This is a necessary first step toward understanding the dynamics of viral infection of Perkinsus spp. cells and the effects of viruses on the propagation and virulence of this protozoan parasite. In this study, work will focus on the three Perkinsus spp. (P. marinus, P. chesapeaki, and P. olseni) for which there is previous evidence of viral infection. The investigators will isolate viruses specific to several Perkinsus strains already in culture as well as from new Perkinsus spp. isolates. Effort will be put in establishing cultures from those isolates and to optimize propagation and maintenance of the viruses in the laboratory. They will also conduct growth curve experiments, and investigate the effect of viral infection on Perkinsus physiology and as a potential trigger for cell differentiation. Having well characterized model virus-host systems in culture is essential to investigate the environmental parameters that affect viral replication success and specificity. It will also aid in understanding the mechanisms of virus-host interactions and their ecological and physiological consequences through hypothesis driven experimental manipulation. Overall, this project will help to evaluate the ubiquity of viruses that infect Perkinsus spp. and the roles they play in shaping the life cycle and the virulence of these parasites of bivalves.

牡蛎和蛤经常受到寄生虫的挑战，包括帕金虫属物种。 Perkinsus spp.是皮肤病的病原体，可导致养殖和野生双壳贝类群体的大量死亡，因此具有严重的有害生态和经济后果。帕金瑟病被列入世界动物卫生组织的可报告疾病清单。大多数旨在了解和干预 Dermo 的研究都集中在寄生虫和宿主的二人博弈上。然而，之前的超微结构研究表明，寄生虫的细胞核中存在病毒样颗粒。然而，我们对这些病毒的遗传学、感染机制或对帕金瑟斯生态的影响一无所知。对其他寄生原生动物（包括一些以人类为宿主）的研究揭示了许多有趣的生物现象，这些现象表明，有充分的理由预期病毒对帕金虫属的繁殖、生活方式和毒力具有深远的影响。证明 Perkinsus spp 的病毒感染。了解宿主对感染的功能反应将代表我们对帕金菌属的思考范式的转变。生态学和对其双壳类宿主的毒力。此外，它将为干预致病因子的新方法打开大门。该项目被认为是高风险高回报，因为迄今为止，感染帕金瑟斯病毒的令人信服的证据是基于使用电子显微镜进行的超微结构研究，但缺乏评估病毒分离难易程度的信息。该项目的重点是分离和鉴定感染帕金菌属的病毒。这是了解 Perkinsus spp 病毒感染动态的必要的第一步。细胞以及病毒对这种原生动物寄生虫的繁殖和毒力的影响。在这项研究中，工作将集中在三种 Perkinsus spp 上。 （P. marinus、P. chesapeaki 和 P. olseni），先前有病毒感染的证据。研究人员将分离出针对已培养的几种帕金氏菌菌株以及新的帕金氏菌属特有的病毒。隔离。我们将努力从这些分离株中建立培养物，并优化病毒在实验室中的繁殖和维持。他们还将进行生长曲线实验，并研究病毒感染对帕金瑟斯生理学的影响以及作为细胞分化的潜在触发因素。在培养物中拥有良好表征的模型病毒宿主系统对于研究影响病毒复制成功和特异性的环境参数至关重要。它还将有助于通过假设驱动的实验操作来理解病毒与宿主相互作用的机制及其生态和生理后果。总体而言，该项目将有助于评估感染 Perkinsus spp 的病毒的普遍性。以及它们在影响双壳类寄生虫的生命周期和毒力方面所发挥的作用。