Charactering mucosal parasitism by Trichomonas vaginalis and Trichomonas gallinae through comparative genomics, transcriptomics, molecular and biochem

通过比较基因组学、转录组学、分子和生物化学表征阴道毛滴虫和鸡毛滴虫的粘膜寄生特征

• 批准号: 1960458
• 金额: --
• 依托单位: Newcastle University
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1960458
• 关键词: Charactering; mucosal; parasitism; Trichomonas; vaginalis

Species of the genus Trichomonas are parasitic protozoa of vertebrates that include important pathogens inflicting morbidity and in some contexts significant mortality rates in infected populations. Trichomonas vaginalis (TV) is the most common human cellular STD worldwide - 277 millions new cases in 2008 (WHO). TV induces significant health sequelae including facilitating the spread of HIV, preterm birth and is associated with cervical and aggressive prostate cancers. Other Trichomonas species are known to infect birds and Trichomonas gallinae (TG), common in Columbiformes (e.g. pigeons), emerged as a novel fatal disease of finches (death of 1.5 million greenfinches, 35% of population) in 2005/6 in the UK.In this project we propose to exploit three sets of important new data to characterise Trichomonas virulence factors targeting host glycoproteins: (i) identification of a novel TV cell surface metallopeptidase mediating human cell cytolysis via binding to proteoglycans, (ii) phylogenetics supporting close relationships between human and bird Trichomonas species suggesting zoonotic origins for human parasites and (iii) novel genome sequence data for several Trichomonas species from birds and humans. Recent data (PhD student, supervisors Hirt and Bolam, collaborator Johnson, UCLA) indicate that TV is adhering to and degrading human surface proteoglycans of both vaginal epithelial cell (VEC) and prostate cells (PC) using a surface metalloprotease (M60-like) possessing two carbohydrate-binding modules (CBMs) binding heparan sulphate (HS). Significantly TV overexpressing the M60-like protein leads to an increase of VEC and PC cytolysis. In contrast, human cell cytolysis was significantly reduced when interfering with either TV binding to HS or the M60-like protease activity. Investigation of the initial genome sequence data for one UK bird isolate of TG, implicated in UK finch population decline, identified 16 M60-like homologues with the same structural configuration as the aforementioned TV M60-like protein.The PhD student will investigate candidate virulence factors from Trichomonas spp. potentially targeting bird and human glycoproteins by combining comparative genomics, transcriptomics, biochemistry and cell biology. Comparative genomics and transcriptomics (from both in vitro and in vivo complementary experiments) will be exploited to identify common and highly expressed genes encoding CBMs, CAZymes (carbohydrate active enzymes) and proteases of bird and human pathogens to gain a global picture of how Trichomonas targets host glycans and glycoproteins. The gene annotations and transcriptomics data will be integrated to select a handful of TV and TG proteins for their functional characterisation focusing on peptidases associated with CBMs to test their glycan binding and protease specificity and their impact on host cells.

毛滴虫属的物种是脊椎动物的寄生原生动物，其包括在感染人群中造成发病率和在某些情况下显著死亡率的重要病原体。阴道毛滴虫（TV）是全世界最常见的人类细胞性STD-2008年有2.77亿新病例（WHO）。电视会引起严重的健康后遗症，包括促进艾滋病毒的传播、早产，并与宫颈癌和侵袭性前列腺癌有关。已知其他毛滴虫属物种感染鸟类和鸡毛滴虫（TG），常见于鸽形目（例如鸽子），作为雀类的一种新的致命疾病出现（死亡150万绿雀，占种群的35%）。在这个项目中，我们提出利用三组重要的新数据来鉴定毛滴虫毒力因子靶向宿主糖蛋白：（i）鉴定了一种通过与蛋白聚糖结合介导人类细胞溶解的新型TV细胞表面金属肽酶，（ii）支持人类和鸟类毛滴虫物种之间密切关系的遗传学，表明人类寄生虫的人畜共患起源，以及（iii）来自鸟类和人类的几种毛滴虫物种的新基因组序列数据。最近的数据（博士生，导师Hirt和Bolam，合作者约翰逊，加州大学洛杉矶分校）表明，电视是粘附和降解阴道上皮细胞（VEC）和前列腺细胞（PC）的人表面蛋白聚糖使用的表面金属蛋白酶（M60样）具有两个碳水化合物结合模块（CBM）结合硫酸乙酰肝素（HS）。显著地，TV过表达M60样蛋白导致VEC和PC细胞溶解的增加。相反，当干扰TV与HS的结合或M60样蛋白酶活性时，人细胞的细胞溶解显著降低。调查的初始基因组序列数据的一个英国鸟类分离的TG，牵连在英国雀种群下降，确定了16 M60样同系物与上述电视M60样蛋白相同的结构配置。通过结合比较基因组学、转录组学、生物化学和细胞生物学，潜在地靶向鸟类和人类糖蛋白。将利用比较基因组学和转录组学（来自体外和体内互补实验）来鉴定编码鸟类和人类病原体的CBM、CAZymes（碳水化合物活性酶）和蛋白酶的常见和高度表达的基因，以获得毛滴虫如何靶向宿主聚糖和糖蛋白的全局图。将整合基因注释和转录组学数据，以选择少数TV和TG蛋白进行功能表征，重点是与CBM相关的肽酶，以测试其聚糖结合和蛋白酶特异性及其对宿主细胞的影响。