Sonic hedgehog-regulated myotome formation relies on the myomiR, miR-133

Over the past two decades a great deal of information has been provided concerning myogenesis—the process of skeletal muscle formation. Much is known about the cellular and molecular mechanisms of adult myogenesis—the process through which adult muscle regenerates following acute injury and embryonic myogenesis—the process of skeletal muscle tissue development (1,2); however, the picture of the molecular mechanisms governing myogenesis is far from being complete. A recent paper by Mok et al. (3) adds an important piece of information to the mosaic of molecules/factors driving the ordered sequence of muscle-related events leading to cell fate decisions in developing embryos.