Functional Genemics of Cryptosporidium parvum

描述(由申请人提供)：这是一份修订后的拨款申请，用于研究微小隐孢子虫和感染这种寄生虫的宿主细胞中的全球基因表达。微小隐孢子虫是艾滋病患者的一种机会性病原体，也是全球儿童腹泻的常见原因。微小弧菌基因组的完整序列为确定药物靶标和在基因组和功能水平上研究这种寄生虫提供了新的机会。在这个项目中，DNA微阵列将用于研究寄生虫的基因调控和宿主细胞对这种感染的反应。对全球寄生虫转录的分析，主要是在胞外、宿主细胞入侵和细胞内发育的初始阶段，将确定寄生虫的生化途径，这些途径在生命周期的这一阶段有差异表达。在培养和动物模型中分析受感染宿主细胞的转录反应将确定宿主对感染做出反应的机制，并阐明导致隐孢子虫病肠道症状的分子途径。这个项目是两个研究小组之间的合作努力，他们在微小隐孢子虫的生物学和基因组学方面具有互补的专业知识，并拥有广泛的合作经验。 在具体目标1中，将开发一个包含微小隐孢子虫所有基因的综合DNA微阵列。这项任务将利用基因组序列，将基因组信息转化为识别与寄生虫发育相关的遗传过程的工具。在特定的目标中，根据目标1开发的2个微阵列将用于探测卵囊过度结晶、宿主细胞入侵和第一代融合过程中的全球基因表达。特殊目的3将使用商业上可获得的人类和小鼠基因阵列来研究宿主细胞对微小弧菌的反应。将比较宿主细胞对1型和2型微小弧菌的反应，以探索观察到的不同类型之间毒力差异的分子基础。

DESCRIPTION (provided by applicant): This is a revised grant application to study global gene expression in Cryptosporidium parvum and in host cells infected with this parasite. Cryptosporidium parvum is an opportunistic pathogen in people with AIDS and is a common cause of diarrhea in children worldwide. The completed sequence of the C. parvum genome provides new opportunities for identifying drug targets and for research on this parasite on a genomic and functional level. In this project DNA microarrays will be used to study parasite gene regulation and the response of the host cell to this infection. Analysis of global parasite transcription, primarily during excystation, host cell invasion, and the initial phase of intracellular development will identify parasite biochemical pathways, which are differentially expressed during this phase of the life cycle. Analysis of the transcriptional response of infected host cells in culture and in animal models will identify mechanisms by which the host responds to the infection, and shed light on the molecular pathways leading to the intestinal symptoms of cryptosporidosis. This project is a collaborative effort between two research groups with complementary expertise in the biology and genomics of C. parvum and extensive collaborative experience. In Specific Aim 1 a comprehensive DNA microarray containing all of the genes of C. parvum will be developed. This task will take advantage of the genomic sequence by converting genomic information into a tool for identifying genetic processes associated with parasite development. In Specific Aim 2 microarrays developed under aim 1 will be used to probe global gene expression during oocyst excystation, host cell invasion, and first generation merogony. Specific Aim 3 will use commercially available human and mouse gene arrays to study the response of the host cell to C. parvum. A comparison of the host cell response to C. parvum type 1 and type 2 will be performed to probe the molecular basis of the observed difference in virulence between types.