Cytoneme-mediated hedgehog signaling in cardiac development

心脏发育中细胞因子介导的刺猬信号

• 批准号: 9760368
• 负责人: Brent Malcolm Wood
• 金额: $ 6.12万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9760368
• 关键词: 3-Dimensional; Actins; Adult; Agonist; Architecture; Calcium; Cardiac; Cardiac development; Cells; Cellular Structures; Characteristics; Clinical Trials; Congenital Heart Defects; Coronary; Coupling; Development; Disease; Dorsal; Drosophila genus; Ectoderm; Electron Microscopy; Embryo; Endocytic Vesicle; Erinaceidae; Etiology; Filopodia; Future; Gene Expression; Gene Expression Profile; Glutamates; Goals; Heart; Individual; Intracellular Membranes; Label; Light; Mediating; Membrane; Mesoderm; Mesoderm Cell; Morphology; Muscle Cells; Myocardial Infarction; Myocardium; Neurons; Organ; Paracrine Communication; Pathway interactions; Pattern; Pharmacology; Process; Regenerative Medicine; Resolution; Safety; Side; Signal Transduction; Specificity; Structure; Synapses; System; Target Populations; Testing; Thinness; Tissues; Travel; Tube; Wing; Work; angiogenesis; base; cell type; confocal imaging; coronary vasculature; exosome; extracellular; hedgehog signal transduction; imaginal disc; insight; light microscopy; microscopic imaging; morphogens; preservation; regenerative; small molecule; smoothened signaling pathway; therapeutic target

Project Summary / Abstract Hedgehog (Hh) signaling is a critical initiator of developmental patterning in many tissues and organs including the heart. Beyond development, Hh signaling acts to promote angiogenesis and epicardial regenerative capacity, preserve function after myocardial infarction, and maintain coronary vasculature in adult myocardium. Cardiac development requires trans-tissue Hedgehog signaling that is specifically received by a subset of cardiac mesodermal cells. This study will test whether Hedgehog is transported by specialized signaling filopodia known as cytonemes from the embryonic ectoderm to its target cells. Cytonemes are thin actin-based filopodia which connect paracrine signal producing cells to receiving cells. Cytonemes have been shown to be the mechanism by which morphogens are dispersed in many other developmental systems but have never been specifically examined in cardiac development. We hypothesize that cytonemes extending between the dorsal ectoderm and cardioblasts are responsible for the specificity of Hh distribution. The presence, function and necessity of Hh- carrying cytonemes for cardiac tube development will be assessed using live confocal imaging of embryos which express fluorescently tagged CD4 and Hh in the Drosophila embryonic ectoderm, mesoderm, or cardioblasts. To further examine how cytonemes distribute Hh, electron microscopy (EM) will be used in the Drosophila larval imaginal wing disc, where cytonemes have been well-established. Because cytonemes share some characteristics of neurons, we will test whether a bouton structure is found at the junction between cytonemes and their target cells. EM imaging will also be used to answer whether cytonemes connect to multiple or single cells, and how Hh is transported along the cytonemes (e.g. membrane associated exosomes, intracellular membrane, endocytic vesicles). Identification of cytoneme-mediated Hh delivery during cardiac development would expand the way in which we understand and potentially target congenital heart defects, and influence future approaches in regenerative medicine.

项目概要/摘要 Hedgehog (Hh) 信号是许多组织和器官发育模式的关键启动子，包括 心脏。除了发育之外，Hh 信号传导还可促进血管生成和心外膜再生能力， 保存心肌梗塞后的功能，维持成人心肌的冠状动脉血管系统。心脏 发育需要跨组织 Hedgehog 信号传导，该信号传导由心脏的子集专门接收 中胚层细胞。这项研究将测试刺猬是否通过已知的特殊信号丝状伪足进行运输 作为从胚胎外胚层到其靶细胞的细胞因子。细胞质是基于肌动蛋白的薄丝状伪足 将旁分泌信号产生细胞与接收细胞连接起来。细胞因子已被证明是其机制 形态发生素通过这种方式分散在许多其他发育系统中，但从未被专门研究过 检查心脏发育。我们假设细胞线在背侧外胚层和背侧外胚层之间延伸 成心细胞负责 Hh 分布的特异性。 Hh-的存在、功能和必要性 携带用于心管发育的细胞因子将使用胚胎的实时共聚焦成像进行评估， 在果蝇胚胎外胚层、中胚层或成心细胞中表达荧光标记的 CD4 和 Hh。 为了进一步研究细胞因子如何分布 Hh，将在果蝇幼虫中使用电子显微镜 (EM) 成虫翼盘，细胞线已在此处发育良好。因为细胞因子共享一些 神经元的特征，我们将测试细胞线之间的连接处是否发现布顿结构 及其靶细胞。 EM 成像还将用于回答细胞线是否连接到多个或单个 细胞，以及 Hh 如何沿着细胞线转运（例如膜相关的外泌体、细胞内 膜、内吞囊泡）。心脏发育过程中细胞因子介导的 Hh 传递的鉴定 将扩大我们理解和潜在针对先天性心脏缺陷的方式，并影响 再生医学的未来方法。