Functional genomics of molluscan schistosome development

软体动物血吸虫发育的功能基因组学

• 批准号: 6918926
• 负责人: TIMOTHY P. YOSHINO
• 金额: $ 30.72万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6918926
• 关键词: Biomphalaria; RNA interference; Schistosoma mansoni; biotechnology; developmental genetics; embryo /fetus tissue /cell culture; functional /structural genomics; gene expression; gene expression profiling; helminth genetics; host organism interaction; invertebrate embryology; laboratory mouse; larva; metamorphosis; microarray technology; parasitism

DESCRIPTION (provided by applicant): The long-term goal of the proposed research is to identify and functionally characterize the genes regulating intramolluscan larval development in the human blood fluke Schistosoma mansoni. Schistosome development within the snail intermediate host is complex, involving several stages including the snail-infective miracidium, mother sporocyst, daughter sporocyst, and finally the human-infective cercaria. Because the miracidium -to-mother sporocyst transition is assumed to involve numerous physiological adaptations going from its free-living to parasitic existence, it is hypothesized that such a transition is regulated by critical, stage-specific changes in gene expression. Similarly, the initiation of asexual reproduction (embryogenesis) in mother sporocysts to give rise to multiple daughter sporocysts and within daughters, the formation of cercariae, is presumed to involve developmental processes orchestrated through the differential expression of genes in a stage-specific fashion. However, to date, very little is known regarding the identity of genes expressed in molluscan larval stages, especially the asexually reproducing sporocysts, and there exists no information on changes in gene expression profiles associated with sequential development from the miracidium to mother sporocyst to daughter sporocyst stages. To address this critical information gap, and to begin investigating the hypothesis that larval development is driven by defined stage-specific changes in gene expression, the following specific aims are proposed: (1) to evaluate gene expression profiles for miracidia and mother sporocysts (early-and late-developing) under in vitro culture conditions by employing S. mansoni oligonucleotide gene microarrays; (2) to confirm and validate in vitro DNA microarray results by measuring expression of specific genes in mother sporocysts developing under in vivo infections conditions; (3) to investigate the effects of snail host factors on larval schistosome gene expression using schistosome gene microarray analyses, followed by identification and characterization of larval expression-modulating snail molecules; and (4) to evaluate whether specific genes found to be upregulated in a larval stage-associated manner are functionally tied to defined developmental phenotypes using double-stranded RNA interference methods. It is anticipated that the proposed microarray profiling approach will fill a critical information gap regarding S. mansoni larval stage-associated gene expression, and will provide important insights into the role of specific genes in regulating the developmental process. Results of this work may lead to novel strategies for controlling infections within the snail host by disrupting specific larval development-dependent genes or their products.

描述（由申请人提供）：拟议的研究的长期目标是识别并在功能上表征调节人体血液氟血吸虫中的内膜内幼虫发育的基因。蜗牛中间宿主中的血吸虫发育很复杂，涉及多个阶段，包括蜗牛感染性奇迹，孢子囊母亲，女儿孢子囊，最后是人类感染的cercaria。由于假定母孢子型转变的奇迹症涉及从其自由生活到寄生虫存在的许多生理适应，因此假设这种过渡受到基因表达的关键，阶段特异性变化的调节。类似地，假定在母孢子囊中的无性繁殖（胚胎发生）引起多个子女子孢子囊肿，并且在女儿中引起了cercariae的形成，可以涉及涉及通过基因在阶段特定方式中通过基因差异表达来策划的发展过程。 但是，迄今为止，关于在软体动物幼虫阶段表达的基因的身份，尤其是无性繁殖的孢子囊肿，几乎没有知之甚少，并且没有关于基因表达谱的变化的信息，这些变化与从奇迹到母孢子虫到子孢子的序列发育相关的基因表达概况变化。解决这些关键信息 差距，并开始研究以下假设：幼虫发育是由基因表达的定义阶段特异性变化驱动的，提出了以下特定目的：（1）在体外培养条件下通过使用S. Mansonioligonucoinucetiide Microarrays; （2）通过测量表达来确认和验证体外DNA微阵列结果 在体内感染条件下发育的母孢子囊中特定基因的特定基因； （3）研究蜗牛宿主因子对幼虫螺杆基因表达的影响，使用棘体基因微阵列分析，然后鉴定和表征幼虫表达调节蜗牛分子的影响； （4）用双链RNA干扰方法在功能上将发现以幼虫相关的方式上调的特定基因是否与确定的发育表型相关。预计提议 微阵列分析方法将填补有关S. Mansoni幼虫阶段相关基因表达的关键信息差距，并将为特定基因在调节发育过程中的作用提供重要的见解。这项工作的结果可能会导致新颖的策略 通过破坏特定的幼虫发育依赖性基因或其产品来控制蜗牛宿主内的感染。