The present invention provides C1orf54 polypeptides and variants thereof with myokine activity as well as compositions and methods for treating, ameliorating or preventing muscle-related disorders.本發明提供了具有肌肉因子活性的C1orf54多肽及其變體,以及用於治療、減輕或預防肌肉相關障礙之組成物及方法。