Endosomal trafficking and functions in cardiomyocytes: insights from Arf6 signaling

心肌细胞内体运输和功能：Arf6 信号传导的见解

• 批准号: RGPIN-2019-06810
• 负责人: AugerMessier, Mannix
• 金额: $ 2.33万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=760581
• 关键词: Endosomal; trafficking; functions; cardiomyocytes; insights

The long-term vision of our research program is to better understand a fundamental trafficking mechanism that dictate how some proteins reach the surface of contractile cells from the heart, namely the cardiomyocytes. To achieve such goal, we first propose to study, by genetic manipulation of mice, how the removal of a protein named Arf6, an important regulator of protein trafficking in other cells, is impacting heart function. Cell-surface proteins affected by the removal of Arf6 will be further analysed to establish how Arf6 impacts the localization and/or degradation of these proteins and how it affects their function at the membrane of cardiomyocytes. Moreover, we will investigate the role of Arf6 in the genesis and release of cardiac-derived exosomes, which are small vesicles released by cardiomyocytes in their immediate environment and the general circulation before being uptake by other cells. Notably, we will determine how the absence of Arf6 affects the number of exosomes released by cardiomyocytes, but also their protein and miRNA content using unbiased proteomic assays and miRNA screens, respectively. Surprisingly, while this conserved communication system between cells has gained interest in the past years, the mechanisms involved in the production of these exosomes are not yet completely understood. Hence, we expect that our findings will deepen our knowledge about the cardiac endosomal and exosomal trafficking, a fundamental but still enigmatic cellular process in cardiomyocyte's biology. The discoveries originating from this research program will provide benefits to multiple individuals and groups. First, the highly qualified personnel (HQP) formed in my laboratory will benefit from a stimulating research environment. These HQP will become expert in cardiac biology, molecular signaling, genetic manipulation, and related state of the art technology, like echocardiography assessment of murine model, to address the most pressing challenges in the cardiac research field. Also, considering the growing interest in fundamental cardiovascular research and the novel aspects of this research program, we believe our discoveries will generate transposable knowledge that will lead forward the hypothesis and discoveries of other research groups in their own field of expertise.

我们研究计划的长期视觉是更好地了解一种基本的贩运机制，该机制决定了一些蛋白质如何从心脏（即心肌细胞）到达收缩细胞的表面。为了实现此类目标，我们首先建议通过对小鼠的遗传操纵进行研究，如何去除名为ARF6的蛋白质（其他细胞中蛋白质运输的重要调节剂）如何影响心脏功能。将进一步分析受ARF6去除影响的细胞表面蛋白，以确定ARF6如何影响这些蛋白质的定位和/或降解，以及它如何影响其在心肌细胞膜上的功能。此外，我们将研究ARF6在心脏衍生的外泌体的起源和释放中的作用，这些外泌体是由心肌细胞在其附近环境中释放的小囊泡和其他细胞摄入的一般循环。值得注意的是，我们将确定ARF6的不存在如何影响心肌细胞释放的外泌体数量，以及使用无偏的蛋白质组学测定和miRNA筛选的蛋白质和miRNA含量。令人惊讶的是，尽管在过去几年中，这种保守的通信系统引起了人们的兴趣，但尚未完全了解这些外泌体的生产机制。因此，我们预计我们的发现将加深我们对心脏内体和外泌体贩运的了解，这是心肌细胞生物学中的基本但仍然神秘的细胞过程。源自该研究计划的发现将为多个个人和群体带来好处。首先，在我的实验室中形成的高素质人员（HQP）将受益于刺激的研究环境。这些HQP将成为心脏生物学，分子信号传导，遗传操纵和相关技术的专家，例如对鼠模型的超声心动图评估，以应对心脏研究领域中最紧迫的挑战。同样，考虑到对基本心血管研究的兴趣日益增长的兴趣以及该研究计划的新颖方面，我们认为我们的发现将产生可替代知识，这将导致在自己的专业知识领域中其他研究小组的假设和发现。