Molecular mechanisms of Trypanosoma cruzi induced colon pathogenesis

项目摘要 原生动物寄生虫克氏锥虫是南美锥虫病的病原体， 在患病个体中引起严重发病率、死亡率和经济负担的疾病。疾病， 最初在拉丁美洲国家流行，现在已成为所有主要国家的一个新的全球健康问题。 经济发达的国家，由于现代全球化。约30%的T.克氏病毒感染者 最终表现为心脏、胃肠道和/或神经系统疾病或其组合。 巨结肠是南美锥虫病的主要病理之一， 消化道和胃肠道动力障碍。T.克氏感染导致心脏、胃肠道 和神经系统疾病仍在调查中。本提案的目的 是破译T.在早期感染期间， 到巨结肠病理学河马信号通路已被确定为纤维化疾病的贡献者 跨组织类型。下游hippo效应分子雅普的激活启动纤维化的转录 基因.我们最近发现T. cruzi在感染早期激活雅普核翻译， 心脏内皮细胞先前研究表明，寄生虫可上调TSP-1， 以促进感染。心脏内皮细胞中TSP-1基因敲除降低雅普平均荧光 细胞核内的强度，表明在T. 克氏感染PIWI相互作用RNA（piRNA）是一类小的非编码RNA，其在胃肠道中起作用。 如胃癌、结肠癌和结肠直肠癌的疾病。我们最近发现piRNA可以 靶向和调节T. cruzi发病机制，如TGFB 1，FOS和NFATC 2。但 在T.克氏感染根据这些观察， 我们假设，在早期阶段，寄生虫对hippo信号通路和piRNAs的调节异常， 感染该假设将通过以下具体目标进行评估：（1）评估 在T.（2）评估piRNA和PIWIL的作用 蛋白质在感染早期调节下游促纤维化基因。这个项目是 重要的是，它将：确定河马信号转导过程中的作用T。结肠细胞的克氏感染;描绘 TSP-1和hippo信号在寄生虫感染过程中的相互作用;表征PIWIL蛋白的功能作用 并且piRNA显示在使用原代人结肠上皮和平滑肌的感染期间增加 细胞在实习期间，我将能够巩固和获得新的技术技能， 手稿，并参与职业发展活动，如科学交流，科学写作， 和教学Meharry医学院和Meharry-Vanderbilt联盟为此提供设备 项目

Project Summary The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease, a neglected tropical disease which causes severe morbidity, mortality, and economic burden in afflicted individuals. The disease, originally endemic in Latin American countries, has now become a new global health problem in all major economically advanced countries due to modern globalization. About 30% of T. cruzi infected individuals eventually present with cardiac, gastrointestinal tract and/or neurological disorders or a combination thereof. Megacolon, one of Chagas disease major pathologies, is accompanied by an enlarged, fibrotic gastrointestinal tract and GI motility disorders. The mechanisms through which T. cruzi infection causes cardiac, gastrointestinal and neurological disorders in afflicted individuals remains under investigation. The objective of this proposal is to decipher the molecular mechanisms dysregulated by T. cruzi during early infection that contribute to megacolon pathology. The hippo signaling pathway has been identified as a contributor to fibrotic disease across tissue types. Activation of downstream hippo effector molecule YAP initiates transcription of fibrotic genes. We recently showed that T. cruzi activates YAP nuclear translation during the early phase of infection of heart endothelial cells. Thombospondin-1 (TSP-1) was previously shown to be upregulated by the parasite in order to facilitate infection. Knockout of TSP-1 in heart endothelial cells decreased YAP mean fluorescence intensity within the nucleus, indicating that TSP-1 actively interacts with the hippo signaling pathway during T. cruzi infection. PIWI-interacting RNAs (piRNAs), a class of small noncoding RNAs, contribute to gastrointestinal diseases such as gastric cancer, colon cancer, and colorectal cancer. We recently showed that piRNAs can target and regulate genes involved in T. cruzi pathogenesis, such as TGFB1, FOS, and NFATC2. However, the role of piRNAs have not been investigated in colon cells during T. cruzi infection. Based on these observations, we hypothesize that the parasite dysregulates the hippo signaling pathway and piRNAs during the early phase of infection. The hypothesis will be evaluated with the following specific aims: (1) Evaluate the dysregulation of hippo signaling pathway during early phase of T. cruzi infection and (2) Asses the role of piRNAs and PIWIL proteins in the regulation of downstream profibrotic genes during the early phase of infection. This project is significant because it will: identify the role of hippo signaling during T. cruzi infection of colon cells; delineate TSP-1 and hippo signaling interplay during parasite infection; characterize the functional roles of PIWIL proteins and piRNAs shown to be increased during infection using primary human colon epithelial and smooth muscle cells. During the fellowship training period, I will be able to solidify and gain new technical skills, prepare manuscripts, and participate in career developing activities such as scientific communication, scientific writing, and teaching. Meharry Medical College and Meharry-Vanderbilt alliance provide access to equipment for this project.