Ghazi A, Anant S, VijayRaghavan K
National Centre for Biological Sciences, TIFR, Bangalore 560065, India.
Development. 2000 Dec;127(24):5309-18. doi: 10.1242/dev.127.24.5309.
Two physiologically distinct types of muscles, the direct and indirect flight muscles, develop from myoblasts associated with the Drosophila wing disc. We show that the direct flight muscles are specified by the expression of Apterous, a Lim homeodomain protein, in groups of myoblasts. This suggests a mechanism of cell-fate specification by labelling groups of fusion competent myoblasts, in contrast to mechanisms in the embryo, where muscle cell fate is specified by single founder myoblasts. In addition, Apterous is expressed in the developing adult epidermal muscle attachment sites. Here, it functions to regulate the expression of stripe, a gene that is an important element of early patterning of muscle fibres, from the epidermis. Our results, which may have broad implications, suggest novel mechanisms of muscle patterning in the adult, in contrast to embryonic myogenesis.
两种生理上不同类型的肌肉，即直接飞行肌和间接飞行肌，由与果蝇翅盘相关的成肌细胞发育而来。我们发现，直接飞行肌是由成肌细胞群中Apterous（一种Lim同源域蛋白）的表达所决定的。这表明了一种通过标记有融合能力的成肌细胞群来确定细胞命运的机制，这与胚胎中的机制不同，在胚胎中肌肉细胞命运是由单个奠基性成肌细胞决定的。此外，Apterous在发育中的成虫表皮肌肉附着位点表达。在这里，它的作用是调节来自表皮的条纹基因的表达，条纹基因是肌肉纤维早期模式形成的一个重要元素。我们的结果可能具有广泛的意义，它表明了与胚胎肌生成不同的成虫肌肉模式形成的新机制。
