Regulation of muscle fate specification and cell migration in cardiogenic lineage

心源性谱系中肌肉命运规范和细胞迁移的调节

• 批准号: 8527830
• 负责人: Lionel Christiaen
• 金额: $ 36.26万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8527830
• 关键词: Bilateral; Biological Assay; Biological Models; Cardiovascular Diseases; Cardiovascular system; Cell Lineage; Cell division; Cells; Chordata; Ciona intestinalis; Development; Dorsal; Embryo; Enhancers; Fluorescence-Activated Cell Sorting; Gene Expression; Genes; Genetic Transcription; Genome; Heart; Heart Atrium; Heart Block; Individual; Invertebrates; Islet Cell; Larva; Lateral; Medicine; Modeling; Molecular; Molecular Analysis; Molecular Target; Muscle; Muscle Development; Pathway interactions; Pattern; Phenotype; Regenerative Medicine; Regulation; Reporter Genes; Role; Series; Side; Signal Transduction; Skeletal Muscle; Stereotyping; Testing; Time; Tissues; Transcript; Urochordata; base; cell motility; heart cell; heart function; induced pluripotent stem cell; insight; islet; notch protein; novel; precursor cell; progenitor; regenerative therapy; transcription factor

DESCRIPTION (provided by applicant): Understanding the mechanisms directing progressive specification of heart cells from multipotent cardiovascular progenitors is essential for the development of regenerative therapies using induced pluripotent stem (iPS) cells. A simple chordate model system, the tunicate Ciona intestinalis, will be used to analyze the cellular and molecular mechanisms that determine muscle-type specification in the cardiogenic lineage. In Ciona embryos, the bilateral pairs of precardiac cells, called trunk ventral cells (TVCs), undergo stereotyped asymmetric cell divisions that distinguish the heart from the atrial siphon muscle (ASM) precursors. The latter then migrate toward the dorso-lateral atrial siphon placode. Following asymmetric divisions of the TVCs, the genes encoding the transcription factors COE and Islet are specifically up- regulated in the ASMs. In addition, COE is necessary and sufficient to block heart specification and promote the ASM fate, including expression of an ASM-specific Islet enhancer and cell migration toward the dorsal side of the larva. Finally, targeted expression of the constitutively active Notch intracellular domain using a TVC-specific enhancer is sufficient to inhibit ASM- specific expression of COE, Islet and cell migration. These observations led to the hypothesis that the initial asymmetric divisions result in heart-specific Notch signaling, which blocks ASM fate specification, possibly by inhibiting the expression of COE. In order to test this hypothesis, the cis-regulatory sequences that control ASM-specific expression of COE will be isolated and characterized, and the function of Notch signaling upstream of COE will be determined. The expression and localization patterns of endogenous regulators and effectors of Notch signaling will be documented in order to gain insight into the mechanisms that polarize the Notch signal during asymmetric TVC divisions. The effects of Notch signaling, COE and Islet on heart vs. ASM fate specification and cell migration will be analyzed using previously established assays in order to begin to characterize the epistatic relationships between these regulators. Finally, whole genome gene expression changes underlying heart vs. ASM fate specification will be documented by obtaining heart and ASM-specific transcription profiles using fluorescence activated cell sorting and microarrays. The results obtained upon completion of this project will characterize the regulation and function of COE, a novel negative regulator of heart fate specification, and illuminate the cellular and molecular mechanisms controlling muscle fate specification and cell migration in the cardiogenic lineage.

描述（由申请人提供）：了解指导多能心血管祖细胞进行心脏细胞进行性规范的机制对于使用诱导多能茎（IPS）细胞开发再生疗法至关重要。一种简单的脉形模型系统，即贴曲a肠肠肠，将用于分析确定心脏基因谱系中肌肉型规范的细胞和分子机制。在ciona胚胎中，称为中腹细胞（TVC）的双侧双侧细胞对刻板印象的不对称细胞分裂，将心脏与心房虹膜肌肉（ASM）前体区分开。然后，后者朝着多索 - 内侧心房虹吸管位置迁移。在TVC的不对称分裂之后，编码转录因子COE和ISLET的基因在ASM中被特异性调节。此外，COE是必要的，足以阻止心脏规格并促进ASM命运，包括表达ASM特异性胰岛增强子和细胞向幼虫背侧的迁移。最后，使用TVC特异性增强子对组成型活性缺口的靶向表达足以抑制COE，ISLET和细胞迁移的特异性表达。这些观察结果导致了以下假设：初始不对称分裂导致心脏特异性的凹口信号传导，这可能通过抑制COE的表达来阻止ASM命运规格。为了检验这一假设，将分离和表征控制COE ASM特异性表达的顺式调节序列，并且将确定COE上游的Notch信号的功能。将记录内源性调节剂和效应子的表达和定位模式，以便深入了解在不对称TVC部门期间置换信号的机制。 Notch信号，COE和ISLET对心脏与ASM命运规范和细胞迁移的影响将使用先前建立的分析进行分析，以便开始表征这些调节剂之间的同义关系。最后，通过使用荧光激活的细胞分类和微阵列获得心脏和ASM特异性转录谱，将记录整个基因组基因表达在心脏与ASM命运规范的基础变化。该项目完成后获得的结果将表征COE的调节和功能，COE是心脏命运规范的新型负调节剂，并阐明了控制肌肉命运规格和心脏基因谱系中细胞迁移的细胞和分子机制。