Abstract:
The protozoan parasite Entamoeba histolytica causes amoebiasis, a global public health problem. Amoebiasis is solely transmitted by cysts that are produced from proliferative trophozoites by encystation in the large intestine of humans. During encystation, various metabolites, pathways, and cascades sequentially orchestrate the morphological and physiological changes required to produce cysts. Cholesteryl sulfate (CS) has recently been revealed to be among the key molecules that control the morphological and physiological changes of encystation by exerting pleiotropic effects. CS promotes the rounding of encysting Entamoeba cells and maintains this spherical morphology as encysting cells are surrounded by the cyst wall, a prerequisite for resistance against environmental stresses. CS is also involved in the development of membrane impermeability, another prerequisite for resistance. The initiation of cyst wall formation is, however, CS-independent. Here, we overview CS-dependent and -independent processes during encystation and discuss their functional linkage. We also discuss a potential transcriptional cascade that controls the processes necessary to produce dormant Entamoeba cysts.
摘要:
原生动物寄生虫溶组织内阿米巴引起阿米巴病,全球公共卫生问题。阿米巴病仅通过囊肿传播,囊肿是由人类大肠中的增殖滋养体通过包膜产生的。在封闭期间,各种代谢物,通路,和级联顺序协调产生囊肿所需的形态和生理变化。最近发现,硫酸胆固醇酯(CS)是通过发挥多效性作用来控制包膜形态和生理变化的关键分子之一。CS促进包围的内阿米巴细胞的圆化,并保持这种球形形态,因为包围的细胞被囊肿壁包围,抵抗环境压力的先决条件。CS也参与膜不渗透性的发展,抵抗的另一个先决条件。囊肿壁形成的开始是,然而,CS独立。这里,我们概述了封闭过程中依赖CS和独立CS的过程,并讨论了它们的功能联系。我们还讨论了潜在的转录级联,该级联控制产生休眠的内阿米巴囊肿所必需的过程。