Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA.
Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland; Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.
Semin Cell Dev Biol. 2019 Jan;85:36-47. doi: 10.1016/j.semcdb.2017.11.013. Epub 2017 Nov 24.
The Drosophila motor system starts to assemble during embryonic development. It is composed of 30 muscles per abdominal hemisegment and 36 motor neurons assembling into nerve branches to exit the CNS, navigate within the muscle field and finally establish specific connections with their target muscles. Several families of guidance molecules that play a role controlling this process as well as transcriptional regulators that program the behavior of specific motor neuron have been identified. In this review we summarize the role of both groups of molecules in the motor system as well as their relationship where known. It is apparent that partially redundant guidance protein families and membrane molecules with different functional output direct guidance decisions cooperatively. Some distinct transcriptional regulators seem to control guidance of specific nerve branches globally directing the expression of groups of pathfinding molecules in all motor neurons within the same motor branch.
果蝇的运动系统在胚胎发育过程中开始组装。它由每个腹节的 30 块肌肉和 36 个运动神经元组成，这些神经元组装成神经分支离开中枢神经系统，在肌肉场中导航，最后与目标肌肉建立特定的连接。已经确定了几个在控制这个过程中起作用的指导分子家族以及编程特定运动神经元行为的转录调节因子。在这篇综述中，我们总结了这两组分子在运动系统中的作用以及它们之间已知的关系。显然，部分冗余的导向蛋白家族和具有不同功能输出的膜分子协同指导导向决策。一些特定的转录调节因子似乎全局控制特定神经分支的导向，在同一运动分支中的所有运动神经元中指导一组趋化因子分子的表达。
