Cysteine-rich with EGF-like domains 2 – Exodosis and angiogenesis after myocardial infarction

富含半胱氨酸并具有 EGF 样结构域 2 â 心肌梗塞后的外泌和血管生成

• 批准号: 496187875
• 负责人: Professor Dr. Kai Christoph Wollert
• 金额: --
• 依托单位: Klinik für Kardiologie und Angiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/496187875?language=en
• 关键词: Cysteine; rich; EGF; like; domains

Acute myocardial infarction inflicts massive injury to the coronary microcirculation leading to vascular disintegration and capillary rarefication. Within days, a new vascular system develops in the infarct area and helps limiting the extent of scar formation and left ventricular remodelling. The endoplasmic reticulum (ER) plays a pivotal role in the folding, posttranslational modification, and secretion of many autocrine- and paracrine-acting angiogenic growth factors. However, ischemia-reperfusion injury and the increased secretory activity after myocardial infarction may overwhelm ER homeostasis (ER stress). Binding to KDEL receptors determines whether proteins are retained in the ER/Golgi system or are secreted. Accordingly, many ER-resident chaperones possess a classical, C-terminal Lys-Asp-Glu-Leu (KDEL) ER retention signal. Growth factors lacking this motif are secreted. Conversely, proteins with a weak ER retention signal are retained in the ER under basal conditions and are preferentially secreted under ER stress (exodosis). We propose that exodosis provides a mechanism to stimulate angiogenesis specifically in the infarct area. We have performed a single endothelial cell RNA-sequencing-based bioinformatic secretome analysis in the infarct area of mice to identify previously uncharacterised growth factors produced by ER-stressed endothelial cells. We thus identified cysteine-rich with EGF-like domains 2. CRELD2 has a weak ER retention signal (REDL) and is strongly induced during ER stress. Based on our preliminary data, we postulate that endothelial cells release CRELD2 in the infarct area via exodosis to stimulate angiogenesis and wound healing in an autocrine manner. Both hypotheses will be investigated in our project. We intend to measure the expression and secretion of CRELD2 in mice and humans with acute myocardial infarction. We want to study angiogenesis and wound healing after myocardial infarction in globally or conditionally Creld2-deficient mice. We aim to define if CRELD2 acts as an ER resident and/or secreted protein in the infarct area and to explore the therapeutic potential of recombinant CRELD2 after myocardial infarction. Finally, we plan to identify the putative CRELD2 cell surface receptor in endothelial cells and to characterise downstream alterations in the phosphoproteome. Using CRELD2 as an example, our project shall establish exodosis as an important stimulus of angiogenesis and wound healing after myocardial infarction.

急性心肌梗死对冠状动脉微循环造成严重损伤，导致血管崩解和毛细血管稀疏。几天之内，一个新的血管系统在梗死区域发展，并有助于限制瘢痕形成和左心室重塑的程度。内质网（ER）在许多自分泌和旁分泌作用的血管生成生长因子的折叠、翻译后修饰和分泌中起关键作用。然而，缺血再灌注损伤和心肌梗死后分泌活性的增加可能会破坏ER稳态（ER应激）。与KDEL受体的结合决定了蛋白质是保留在ER/高尔基体系统中还是被分泌。因此，许多ER驻留分子伴侣具有经典的C-末端Lys-Asp-Glu-Leu（KDEL）ER滞留信号。缺乏该基序的生长因子被分泌。相反，具有弱ER保留信号的蛋白质在基础条件下保留在ER中，并且在ER应激下优先分泌（外泌）。我们认为，外泌提供了一种机制，刺激血管生成，特别是在梗死区。我们已经进行了一个单一的内皮细胞RNA测序为基础的生物信息学分泌组分析在小鼠的梗死面积，以确定以前未表征的生长因子产生的ER应激内皮细胞。因此，我们确定了富含半胱氨酸的EGF样结构域2。CRELD 2具有弱的ER滞留信号（REDL），并且在ER应激期间被强烈诱导。基于我们的初步数据，我们假设内皮细胞通过外泌在梗死区域释放CRELD 2，以自分泌方式刺激血管生成和伤口愈合。这两个假设都将在我们的项目中进行研究。我们打算测量CRELD 2在患有急性心肌梗死的小鼠和人类中的表达和分泌。我们想在整体或条件性Creld 2缺陷小鼠中研究心肌梗死后的血管生成和伤口愈合。我们的目的是确定CRELD 2是否作为梗死区域的ER驻留和/或分泌蛋白，并探索重组CRELD 2在心肌梗死后的治疗潜力。最后，我们计划鉴定内皮细胞中假定的CRELD 2细胞表面受体，并研究磷酸化蛋白质组的下游改变。以CRELD 2为例，我们的项目将建立外泌作为心肌梗死后血管生成和伤口愈合的重要刺激。