Extracellular vesicles, small RNAs, and intercellular communication in Entamoeba histolytica

溶组织内阿米巴是一种重要的人体病原体。E. 组织溶解性包括痢疾和肝脓肿，该生物体是一种主要的寄生虫死亡原因， 在全球范围基因表达调控是使寄生虫适应宿主的关键因素 在组织侵入期间破坏环境并转化为囊肿阶段并在宿主外传播疾病。 内阿米巴的基因调控机制之一是一个强大而复杂的内源性RNAi途径。超过 在过去的几年里，我们对这一途径进行了重要的观察， 与阿米巴Argonaute蛋白相关，介导转录基因沉默，并具有高度不寻常的5 '- 聚P末端然而，尽管做了大量的努力，我们还没有确定阿米巴生物学的哪些方面是 由小RNA调控，尽管考虑到该途径在相关的内阿米巴中维持，但在体内， 进化压力和明确的生物学作用必须存在。我们最近发现变形虫分泌 细胞外囊泡含有小RNA和RNAi效应蛋白。我们现在要确定 这些含有小RNA的细胞外囊泡作为宿主-寄生物或寄生物-寄生物 细胞间通讯因此，我们将（i）确定阿米巴细胞外的小RNA库 囊泡，（ii）确定它们是否参与细胞间通讯，和（iii）确定蛋白质 EV的组成部分，重点是RNA结合蛋白。这些数据将有助于我们了解 RNA干扰内阿米巴的分子机制，也将扩大我们的理解的作用，小 细胞间通讯中的RNA。我们的工作是在RNA的基本细胞过程的交叉点上- 干扰和阿米巴生物学。数据的出现将有助于理解阿米巴病的发病机制 也有助于扩大对RNAi基本过程的了解。

Entamoeba histolytica, a protozoan parasite, is an important human pathogen. Diseases caused by E. histolytica include dysentery and liver abscesses, and the organism is a leading parasitic cause of death on a global scale. Regulation of gene expression is a key factor that enables the parasite to adapt to the host environment during tissue invasion and to convert to the cyst stage and propagate disease outside the host. One mechanism of gene regulation in Entamoeba is a robust and complex endogenous RNAi pathway. Over the last several years we have made important observations about this pathway including that small RNAs associate with amebic Argonaute protein to mediate transcriptional gene silencing and have highly unusual 5'- polyP termini. However, despite extensive efforts we have not identified which aspects of amebic biology are regulated by small RNAs, although given that the pathway is maintained in related Entamoeba, a strong evolutionary pressure and clear biological role must exist. We have recently identified that ameba secrete extracellular vesicles that contain small RNAs and RNAi effector proteins. We now seek to determine whether these extracellular vesicles containing small RNAs serve as a means of host-parasite or parasite-parasite intercellular communication. Thus, we will (i) identify small RNA repertoire of amebic extracellular vesicles, (ii) determine if they participate in intercellular communication, and (iii) determine protein components of EVs with focus on RNA binding proteins. These data will improve our understanding of the molecular mechanisms of RNAi in Entamoeba and will also broaden our understanding of the roles of small RNAs in intercellular communication. Our work is at the intersection of the basic cellular process of RNA- interference and amebic biology. Data that emerge will contribute to both understanding amebic pathogenesis but also to expanding the knowledge about the fundamental process of RNAi.