Specificity determinants of the cargo content sorted into cell-derived microvesicles

多细胞生物体的正常功能是一个复杂的过程，需要整合自主的细胞活动，包括局部和远程特定的细胞间信号与组织和器官的相互作用。这种无缝功能的核心是细胞外小泡(EV)，特别是外切体。外切体是几乎所有类型的细胞分泌的小的、膜结合的颗粒，大小从30到150纳米不等。每个外切体都含有一组特定的核酸、蛋白质和脂类。外体可以与其他细胞相互作用和/或将其内容转移到目标受体细胞，以精确的方式在功能上改变它们。在组织培养中，已经证明了从一种细胞类型分泌的外切体对远处的其他细胞进行“重新编程”的能力。然而，导致细胞产生一系列包含非常独特和特定的生物信息的外切体的机制仍不清楚。这项研究的主要目的是研究外切体产生的细胞生物学，重点是特定的细胞分子是如何被分类以装载到外切体中的。我们最近发现，感染(丙型肝炎病毒)和细胞应激(酒精)可以诱导细胞释放分子组成与正常情况完全不同的外切体。因此，这项研究计划将评估感染和细胞应激条件如何调节细胞释放的外切体的蛋白质、核酸和脂肪含量的质或量变化。使用病毒感染和体外细胞应激实验模型的组合，我们还将破译和描绘新发现的特定细胞基因和分子如何决定细胞分子的选择和/或排除，以加载和释放外切体。回答这些问题将推动新生的、快速增长的外体细胞生物学领域的发展，并扩大我们对细胞基因谱系和细胞在不同环境下产生特定外体的信号机制的理解。除了提供新的知识，这项研究的许多方面将为所有级别的学生和实习生提供极好的动手机会，因此可以作为发展基础生物学或病毒学事业的关键起点或进步步骤。

The normal functioning of multicellular organisms is a complex process, requiring the integration of autonomous cellular activities involving both local and long-range specific intercellular signaling interactions with tissues and organs. Central to this seamless functioning are extracellular vesicles (EVs), specifically, exosomes. Exosomes are small, membrane-bound particles secreted from almost all cell types ranging in size from 30 to 150 nm. Each exosome contains a specific set of nucleic acids, proteins, and lipids. Exosomes can interact with other cells and/or transfer their content to target recipient cells, functionally altering them in precise ways. The ability of exosomes secreted from one cell type to "reprogram" other cells at a distance has been demonstrated in tissue culture. However, the mechanisms leading to the cellular generation of a repertoire of exosomes containing quite distinct and specific biological messages remain unknown. The main objective of this research is to investigate the cell biology of exosome generation focusing on how specific cellular molecules are sorted for loading into exosomes. We have recently shown that infection (Hepatitis C Virus) and cellular stress (Alcohol) can induce cells to release exosomes with quite distinct molecular composition compared to normal conditions. This research program will, therefore, evaluate how infection and cellular stress conditions modulate the qualitative or quantitative changes in proteins, nucleic acids, and lipids contents of cell-released exosomes. Using a combination of virus infection and cell stress experimental models in-vitro, we will additionally decipher and delineate how newly identified specific cellular genes and molecules determine the selection and/ or exclusion of cellular molecules for loading and release inside exosomes. Answering these questions will advance the nascent, rapidly growing field of exosomal cell biology, and expand our understanding of the repertoire of cellular genes and signaling mechanisms used by cells to generate specific exosomes under different circumstances. In addition to providing new knowledge, many aspects of this research will present excellent hands-on opportunities for students and trainees at all levels, and thus can serve as a critical starting point or advancement step for developing careers in fundamental biology or virology.