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

牡蛎和文蛤经常受到寄生虫的挑战，包括Perkinsus物种。引起皮肤病的Perkinsus spp.可导致养殖和野生双壳贝类种群的大量死亡，从而造成严重的生态和经济后果。帕金索斯在世界动物卫生组织的应报告疾病名单上。大多数旨在了解和干预德尔莫的研究都集中在一个两人的游戏中：寄生虫和宿主。然而，之前的超微结构研究表明，寄生虫的细胞核中存在类似病毒的颗粒。然而，人们对这些病毒的遗传学、感染机制或对Perkinsus生态的影响一无所知。对其他寄生原生动物(包括一些寄生于人类宿主的原生动物)的研究揭示了许多有趣的生物学现象，表明有充分的理由期待病毒对Perkinsus spp的繁殖、生活方式和毒力产生深远的影响。证明Perkinsus spp.的病毒感染。了解宿主对感染的功能性反应将代表着我们对Perkinsus spp思维的范式转变。生态和对其双壳类宿主的毒力。此外，它还将为干预这种致病因子打开新途径的大门。该项目被认为是高风险-高回报的项目，因为到目前为止，感染Perkinsus的病毒的令人信服的证据是基于使用电子显微镜的超微结构研究，但缺乏评估病毒分离容易程度的信息。这个项目的重点是分离和鉴定感染Perkinsus spp的病毒。这是了解Perkinsus spp病毒感染动态的必要的第一步。细胞和病毒对这种原生动物寄生虫繁殖和毒力的影响。在这项研究中，工作重点将集中在三个Perkinsus spp.(P.marinus、P.chesapeaki和P.olseni)，以前有病毒感染的证据。研究人员将从已经在培养中的几个Perkinsus菌株以及新的Perkinsus spp中分离出特定于Perkinsus的病毒。分离株。将努力从这些分离株建立培养物，并优化病毒在实验室的繁殖和维护。他们还将进行生长曲线实验，并调查病毒感染对Perkinsus生理的影响，以及作为细胞分化的潜在触发因素。在培养中具有良好特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是至关重要的。它还将有助于通过假说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。以及它们在塑造这些双壳类寄生虫的生命周期和毒力方面所起的作用。

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.