CELL DEATH IN EMBRYONIC HEAD MUSCLES

鸡胚颅面肌发育的研究进展 意外地显示出大范围的初级肌管中途变性 在胚胎时期。 肌肉细胞死亡（细胞凋亡）是 仅限于在这些胚胎中发育头部和颈部肌肉， 这表明细胞凋亡在建立适当的 颅面肌的功能 的原因和意义 发育中的肌肉细胞的程序性细胞死亡尚不清楚。 的 这里提出的研究将确定程序性细胞死亡的程度 在选定的头部和颈部肌肉，并将调查可能的联系， 纤维类型和肌细胞存活之间的关系。前优雅的细胞死亡 运动神经元已经得到了很好的研究，但是神经元变性的影响 对体内初级肌管的影响尚不清楚。 这将通过以下方式进行分析： 减少运动神经元细胞死亡的程度，并检查 肌肉. 最后，细胞死亡可能是在特定的肌源性 血统 谱系依赖性细胞凋亡将通过移植 非凋亡谱系代替凋亡的肌肉祖细胞。 这些实验将阐明细胞凋亡的原因和作用， 正在发育的颅面肌肉

Recent studies of craniofacial muscle development in chick embryos unexpectedly revealed extensive degeneration of primary myotubes midway through the embryonic period. Muscle cell death (apoptosis) is restricted to developing head and neck muscles in these embryos, suggesting that apoptosis has a role in establishing appropriate functions of craniofacial muscles. The cause(s) and significance of programmed cell death of developing muscle cells are not understood. The research proposed here will define the extent of programmed cell death in selected head and neck muscles, and will investigate possible links between fiber type and muscle cell survival. Pro- graced cell death of motor neurons is well-studied, but the impact of neuronal degeneration on primary myotubes in vivo is not known. This will be analyzed by reducing the extent of motor neuron cell death, and examining the muscles. Finally, cell death may be programmed in specific myogenic lineages. Lineage-dependent apoptosis will be assessed by transplanting non-apoptotic lineages in the place of apoptotic muscle progenitors. These experiments will elucidate the cause(s) and role of apoptosis in developing craniofacial muscles.