Exploring the evolution of the Contractile Vacuole.

探索收缩液泡的演化。

• 批准号: RGPIN-2019-06109
• 负责人: Dacks, Joel
• 金额: $ 5.03万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=738716
• 关键词: Exploring; evolution; Contractile; Vacuole.

Movement of material within the cell, as well as import, export, and cell surface presentation is mediated by the membrane trafficking system (MTS). Its appropriate and successful operation underpins effective cellular function, whether in plants of agricultural importance, parasites of economic impact or algae and protists key to ecosystem balance. Evolving an MTS was key to establishing the eukaryotic cellular configuration and giving rise to nearly all of the biological diversity that we see today. My research program examines the patterns and processes driving the evolution of the MTS. This work provides insights into the fundamental forces that shaped our cellular history and yields important information about modern cell biology. Intriguingly, we have uncovered protein machinery widely present outside of animals and fungi: the cell biology of membrane-trafficking in diverse eukaryotes may differ from well-characterized model systems in ways that are only beginning to be understood. Similarly, while some membrane-trafficking organelles are conserved across eukaryotes, poorly understood organelles are present outside the well-known model systems that are ripe for exploration. The Contractile Vacuole (CV) is an osmoregulatory organelle found in ecologically important freshwater and soil-dwelling organisms. However, it is often not reported as present in parasites or marine organisms, raising questions of whether organelles identified as contractile vacuoles are truly orthologous between diverse eukaryotes. We will use molecular evolutionary and transcriptomic analysis to examine the evolution and function of the CV by two short-term goals, each with sub-projects defined within them. 1: In order to test the simplest null hypothesis that the CV derived from a single homologous ancestor, a sampling of eukaryotes with CVs from across the eukaryotic tree will be investigated. Transcriptomics will be used to determine genes that are differentially expressed upon induction of CV function by osmotic stress. The identity and evolution of these genes will be assessed with the explicit prediction that a common core gene set associated with CV function would imply homology. 2: To complement this taxonomically broad approach, analysis will be focused on a single lineage possessing well-characterized CVs, the ciliates. Molecular evolutionary and transcriptomics across the full taxonomic range of ciliates will assess the machinery that is conserved in CV function, again predicting the presence of a conserved core set. By identifying the genes of importance in CV function and their distribution in eukaryotes, we gain information about the workings of an organelle present in ecologically crucial lineages of eukaryotes. By understanding the evolution of the CV, we will be able to integrate an important organelle into the larger framework of membrane-trafficking evolution and gain a better understanding into the rise of eukaryotic life on Earth.

细胞内物质的运动，以及输入、输出和细胞表面呈递由膜运输系统（MTS）介导。它的适当和成功的运作是有效的细胞功能的基础，无论是在农业重要性的植物，经济影响的寄生虫或藻类和原生生物生态系统平衡的关键。进化MTS是建立真核细胞结构的关键，也是我们今天看到的几乎所有生物多样性的关键。 我的研究项目研究了推动MTS演变的模式和过程。这项工作提供了对塑造我们细胞历史的基本力量的见解，并产生了有关现代细胞生物学的重要信息。有趣的是，我们发现了广泛存在于动物和真菌之外的蛋白质机制：不同真核生物中膜运输的细胞生物学可能与表征良好的模型系统不同，其方式才刚刚开始被理解。类似地，虽然一些膜运输细胞器在真核生物中是保守的，但在成熟的探索模型系统之外存在着知之甚少的细胞器。收缩细胞器（CV）是一种存在于淡水和土壤中的重要的生物调节细胞器。然而，它往往没有报道存在于寄生虫或海洋生物中，提出了一个问题，即被鉴定为收缩泡的细胞器是否真的在不同的真核生物之间存在。 我们将使用分子进化和转录组学分析，通过两个短期目标来研究CV的进化和功能，每个目标都有定义的子项目。 一曰：为了检验CV源自单一同源祖先的最简单的零假设，将研究具有来自真核树的CV的真核生物的采样。转录组学将用于确定渗透压胁迫诱导CV功能后差异表达的基因。这些基因的身份和进化将进行评估，明确预测与CV功能相关的共同核心基因集将意味着同源性。2：为了补充这种分类学上广泛的方法，分析将集中在一个单一的血统拥有良好的特征CV，纤毛虫。分子进化和转录组学在整个分类范围的纤毛虫将评估的机械，是保守的CV功能，再次预测存在一个保守的核心集。通过识别CV功能的重要基因及其在真核生物中的分布，我们获得了关于真核生物生态关键谱系中存在的细胞器的工作的信息。通过了解CV的进化，我们将能够将一个重要的细胞器整合到膜运输进化的更大框架中，并更好地了解地球上真核生命的兴起。