Cellular Mechanisms of Matching Between Fast and Slow Motoneurons and Myotubes

正常神经肌肉发育的一个重要方面是 快、慢运动神经元与适当肌纤维的匹配 类型，但负责这种匹配的机制目前 不明白。 鸡胚是一个适合研究 这个问题，因为涉及的组织很容易操作。 的 适当的神经支配的时间过程将在 鸡后肢肌肉的胚胎发育。 这将决定 如果特异性发生在最初的神经支配，或者如果适当的话， 匹配是通过神经肌肉连接的重新排列产生的。 参与神经元匹配的分子机制， 将研究特定的肌纤维类型。 体外模型 将被用来测试快或慢运动神经元的偏好， 在含有快或慢肌管膜的基质上的生长 件. 此外，由于快速和慢速之间的抗原差异， 肌管膜可以是被识别的表面成分， 神经支配期间的运动神经元，多克隆和单克隆抗体 将提高对慢和快的肌肉表面膜 件. 这些抗体可用于表征 快肌和慢肌之间的分子差异， 在卵细胞发育过程中的识别过程。 这些研究 将提供一个更全面的了解细胞和分子 正常选择性突触发生过程中的事件。

An important aspect of normal neuromuscular development is the matching of fast and slow motoneurons with appropriate muscle fiber types, but the mechanisms responsible for this matching are presently not understood. Embryonic chick is a suitable system for the study of this problem, as the tissues involved are easily manipulated. The time course of appropriate innervation will be determined during embryonic development of chick hindlimb muscle. This will determine if specificity occurs with initial innervation, or if appropriate matching is produced by a rearrangement of neuromuscular connections. The molecular mechanisms involved in the matching of neurons to specific muscle fiber types will be investigated. An in-vitro model will be used to test the preference of fast or slow motoneurons for outgrowth on substrates containing fast or slow myotube membrane components. Also, since antigenic differences between fast and slow myotube membranes may be surface components that are recognized by motoneurons during innervation, polyclonal and monoclonal antibodies will be raised against slow and fast muscle surface membrance components. These antibodies can then be used to characterize molecular differences between fast and slow muscle, and to interfere with the recognition process during development in ovo. These studies will provide a fuller understanding of the cellular and molecular events during normal selective synaptogenesis.