A further feature reported in a number of different models of diseases resulting in muscle atrophy is the substantial up-regulation of two E3 ubiquitin ligases, atrogin-1/MAFbx (FBXO32) and MuRF1 (TRIM63) [38,39], which are generally induced early during the atrophy process. The gene discussed is FBXO32; the disease is Atrophy.