AKT1 and myasthenia gravis: Not only does muscle growth inhibitor play a negative regulatory role in developmental myogenesis, its level is upregulated in several myasthenia gravis and upregulates the expression of E3 ubiquitin ligases (e.g., MuRF1 and MAFbx) by decreasing Akt phosphorylation and activating the FOXO transcription factor, which further stimulates protein degradation [45,57].