Investigating virulence factors in Neoparamoeba perurans causing amoebic gill disease (AGD) in Atlantic salmon

研究引起大西洋鲑鱼阿米巴鳃病 (AGD) 的秘鲁新帕拉米巴的毒力因子

• 批准号: 2072877
• 金额: --
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2072877
• 关键词: Investigating; virulence; factors; Neoparamoeba; perurans

Amoebic gill disease (AGD) is a serious disease affecting the marine-farmed Atlantic salmon, Salmo salar L., industry in Australia and Tasmania, where it costs the industry up to $23M a year in treatment alone. Recently, AGD became an emerging disease in Europe and America accounting for losses of up to one third of the harvest in some cases in Europe (for example in Shetland in 2012). AGD is characterised by multifocal white patches on the gill surface and causes hyperplasia of the epithelial and mucous cells, which can result in areas of lamellar fusion, leading to death due to respiratory failure. The causative agent of AGD is Neoparamoeba perurans, a free living protozoan which colonises the gills. This project will be a collaborative project between Cefas and the University of Exeter and will address the following objectives:Objective 1: Characterisation of the molecular host pathogen interactions in pathogenic and non-pathogenic amoeba - The student will conduct a temporal infection study in which salmon gill cells will be infected with pathogenic N. perurans, an attenuated clone of N. perurans obtained through multiple in vitro passages and a non-pathogenic amoeba (the closely related but non-pathogenic Neoparamoeba pemaquidensis). RNA-Seq analysis will be conducted to quantify changes in gene expression (from both the host and pathogen) over time and comparisons between the three experimental scenarios will allow for the identification of molecular targets from the pathogenic N. Perurans that are expressed during the early stages of infection and differ from the other forms of amoeba. Objective 2: Identification of the genes responsible for the pathogenicity of N perurans - The student will then perform RNAi experiments to determine which genes from those identified above are responsible for the pathogenicity of N. perurans. Double-stranded RNA (dsRNA) will be designed for candidate genes and delivered in vitro to cultured amoebae. The efficacy of RNAi delivery will be tested by gene expression analyses using biomarkers of pathogenicity (for example IL-1beta). Using this in vitro platform, a range of genes will be screened.

阿米巴鳃病 (AGD) 是一种影响澳大利亚和塔斯马尼亚海水养殖大西洋鲑鱼 Salmo salar L. 产业的严重疾病，仅治疗费用每年就高达 2300 万美元。最近，AGD 在欧洲和美洲成为一种新出现的疾病，在欧洲的某些情况下造成了高达三分之一的收成损失（例如 2012 年在设得兰群岛）。 AGD 的特点是鳃表面出现多灶性白斑，导致上皮细胞和粘液细胞增生，从而导致板层融合区域，导致呼吸衰竭而死亡。 AGD 的病原体是新帕拉米巴，一种寄生在鳃上的自由生活的原生动物。该项目将是 Cefas 和埃克塞特大学之间的合作项目，将实现以下目标：目标 1：致病性和非致病性阿米巴原虫中分子宿主病原体相互作用的特征 - 学生将进行一项暂时感染研究，其中鲑鱼鳃细胞将被致病性 N. perurans（通过多次体外传代获得的 N. perurans 减毒克隆）和非致病性阿米巴（密切相关但非致病性新帕拉米巴）感染。佩马奎登斯）。将进行 RNA-Seq 分析以量化基因表达（来自宿主和病原体）随时间的变化，并且三个实验方案之间的比较将允许识别来自致病性 N. Perurans 的分子靶标，这些靶标在早期表达感染阶段，与其他形式的阿米巴变形虫不同。目标 2：鉴定负责 N. perurans 致病性的基因 - 然后学生将进行 RNAi 实验，以确定上述鉴定的基因中哪些基因负责 N. perurans 的致病性。双链RNA（dsRNA）将针对候选基因进行设计，并在体外递送至培养的阿米巴原虫。 RNAi 递送的功效将通过使用致病性生物标志物（例如 IL-1beta）进行基因表达分析来测试。使用这个体外平台，将筛选一系列基因。