Gobert Geoffrey N, Moertel Luke, Brindley Paul J, McManus Donald P
Division of Infectious Diseases & Immunology, Queensland Institute of Medical Research, Brisbane, Queensland, Australia.
BMC Genomics. 2009 Mar 25;10:128. doi: 10.1186/1471-2164-10-128.
The schistosome blood flukes are complex trematodes and cause a chronic parasitic disease of significant public health importance worldwide, schistosomiasis. Their life cycle is characterised by distinct parasitic and free-living phases involving mammalian and snail hosts and freshwater. Microarray analysis was used to profile developmental gene expression in the Asian species, Schistosoma japonicum. Total RNAs were isolated from the three distinct environmental phases of the lifecycle -- aquatic/snail (eggs, miracidia, sporocysts, cercariae), juvenile (lung schistosomula and paired but pre-egg laying adults) and adult (paired, mature males and egg-producing females, both examined separately). Advanced analyses including ANOVA, principal component analysis, and hierarchal clustering provided a global synopsis of gene expression relationships among the different developmental stages of the schistosome parasite.
Gene expression profiles were linked to the major environmental settings through which the developmental stages of the fluke have to adapt during the course of its life cycle. Gene ontologies of the differentially expressed genes revealed a wide range of functions and processes. In addition, stage-specific, differentially expressed genes were identified that were involved in numerous biological pathways and functions including calcium signalling, sphingolipid metabolism and parasite defence.
The findings provide a comprehensive database of gene expression in an important human pathogen, including transcriptional changes in genes involved in evasion of the host immune response, nutrient acquisition, energy production, calcium signalling, sphingolipid metabolism, egg production and tegumental function during development. This resource should help facilitate the identification and prioritization of new anti-schistosome drug and vaccine targets for the control of schistosomiasis.
血吸虫是复杂的吸虫，可引发一种在全球具有重大公共卫生意义的慢性寄生虫病——血吸虫病。它们的生命周期具有独特的寄生和自由生活阶段，涉及哺乳动物宿主、蜗牛宿主和淡水。微阵列分析用于描绘亚洲血吸虫种日本血吸虫的发育基因表达情况。从生命周期的三个不同环境阶段分离总RNA，即水生/蜗牛阶段（卵、毛蚴、胞蚴、尾蚴）、幼虫阶段（肺期童虫和配对但未产卵的成虫）以及成虫阶段（配对的成熟雄虫和产卵雌虫，分别进行检测）。包括方差分析、主成分分析和层次聚类在内的高级分析提供了血吸虫寄生虫不同发育阶段之间基因表达关系的全局概述。
基因表达谱与吸虫在其生命周期中发育阶段必须适应的主要环境背景相关联。差异表达基因的基因本体揭示了广泛的功能和过程。此外，还鉴定出了阶段特异性的差异表达基因，这些基因参与了众多生物途径和功能，包括钙信号传导、鞘脂代谢和寄生虫防御。
这些发现提供了一个重要人类病原体基因表达的综合数据库，包括在发育过程中参与逃避宿主免疫反应、营养获取、能量产生、钙信号传导、鞘脂代谢、产卵和体表功能的基因的转录变化。该资源应有助于促进新的抗血吸虫药物和疫苗靶点的鉴定和优先排序，以控制血吸虫病。
