MYOFIBRIL AND MYOFIBER FORMATION IN THE DEVELOPING HEART

描述：(修改自申请者摘要)正常发展 需要细胞外基质之间的相互作用 和单独的细胞组件。各种复杂的相互作用 导致高效所需的细胞表型和模式 心脏功能。肌细胞的不同模式的形成似乎 与肌原纤维形成有协同关系。这种协调 涉及细胞外基质之间的相互作用，特定的跨膜 受体和细胞骨架。虽然很多人都知道，但考虑到 肌原纤维的组装，关于肌原纤维的作用知之甚少 肌节排列或肌原纤维附着中的细胞骨架 膜和细胞器。建议的研究将会：1)研究 细胞外基质受体(整合素)、细胞骨架成分和核的作用 Lamins在体外肌原纤维形成中；2)使用特异性抗体， 反义寡核苷酸探针和生长因子干扰血管内皮细胞 肌原纤维的形成；3)比较在 体外对整个胚胎培养模型中的肌原纤维形成的影响； 确定肌原纤维生成改变是否会导致肌纤维模式改变 全胚胎培养中肌细胞的形成。小鼠胎心细胞 将在一种独特的培养系统中使用，该系统产生具有 表型与体内所见相似。初步调查将 检测纽蛋白、α-肌动蛋白和整合素的表达。 肌原纤维形成。微量注射反义寡核苷酸和/或 抗体将用于阻断与肌原纤维的相互作用 发展中的关键时期。类似的探头将在整个 胚胎培养以确定异常的肌原纤维生成是否会 导致异常纤维图案。同时，这些数据将提供 加深对肌原纤维组装及其相互关系的认识 到心脏器官发生。

DESCRIPTION: (Modified from applicant's abstract) Normal development of the heart requires an interaction between the extracellular matrix and individual cellular components. A complex variety of interactions result in the cellular phenotypes and patterns necessary for efficient cardiac function. Formation of distinct patterns of myocytes appears to be coordinately associated with myofibrillogenesis. This coordination involves an interaction between the ECM, specific transmembrane receptors and the cytoskeleton. While much is known considering the assembly of myofibrils, little is known concerning the role of the cytoskeleton in alignment of sarcomeres or the attachment of myofibrils to membranes and organelles. The proposed studies will: 1) examine the role of ECM receptors (integrins), cytoskeletal components and nuclear lamins in myofibrillogenesis in vitro; 2) use specific antibody, antisense oligonucleotide probes and growth factors to perturb the formation of myofibrils; 3) compare the patterns and alterations seen in vitro to myofibrillogenesis in the whole embryo culture model; and 4) determine if altered myofibrillogenesis causes altered myofiber pattern formation of myocytes in whole embryo culture. Mouse fetal heart cells will be used in a unique culture system that produces myocytes with a phenotype similar to that seen in vivo. Initial investigations will examine the expression of vinculin, alpha-actinin, and integrins during myofibrillogenesis. Microinjection of antisense oligonucleotides and/or antibodies will be used to block inter- actions with myofibrils at critical times in development. Similar probes will be used in whole embryo culture to determine whether abnormal myofibrillo- genesis will result in abnormal fiber patterns.Together, these data will provide an enhanced understanding of myofibrillar assembly and its relation- ship to cardiac organogenesis.