First, the ubiquitin–proteasome system (UPS) is the major pathway for cellular protein degradation, and studies have demonstrated that activating the UPS leads to increased protein degradation and finally results in sarcopenia (18, 19), while protein or amino acid nutritional support can effectively downregulate the levels of MuRF-1 and Atrogin-1 and ameliorate UPP-mediated sarcopenia (20, 21). The gene discussed is TRIM63; the disease is sarcopenia.