NR0B2 and obesity due to melanocortin 4 receptor deficiency: Small heterodimer partner (SHP, NROB2) plays a critical role in metabolic diseases [1], including bile acid biosynthesis [2], [3], bile acid and bile duct ligation (BDL) induced cholestatic liver injury [4], [5], fatty liver [6], [7], hypercholesterolemia [8], glucose metabolism [9], [10], obesity [11]–[13], and liver fibrosis [14].