Tapscott S J, Thayer M J, Weintraub H
Fred Hutchinson Cancer Research Center, Seattle, WA 98104.
Science. 1993 Mar 5;259(5100):1450-3. doi: 10.1126/science.8383879.
Rhabdomyosarcoma cells express the myogenic helix-loop-helix proteins of the MyoD family but do not differentiate into skeletal muscle cells. Gel shift and transient transfection assays revealed that MyoD in the rhabdomyosarcoma cells was capable of binding DNA but was relatively nonfunctional as a transcriptional activator. Heterokaryon formation with fibroblasts resulted in the restoration of transcriptional activation by MyoD and the differentiation of the rhabdomyosarcoma cells into skeletal muscle cells. These results suggest that rhabdomyosarcomas are deficient in a factor required for MyoD activity.
横纹肌肉瘤细胞表达MyoD家族的生肌螺旋-环-螺旋蛋白，但不会分化为骨骼肌细胞。凝胶迁移和瞬时转染分析表明，横纹肌肉瘤细胞中的MyoD能够结合DNA，但作为转录激活因子相对无功能。与成纤维细胞形成异核体导致MyoD恢复转录激活，横纹肌肉瘤细胞分化为骨骼肌细胞。这些结果表明，横纹肌肉瘤缺乏MyoD活性所需的一种因子。
