INS and diabetes mellitus: However, transgenic mice with selective ablation of INSR in GLUT4 expressing tissues (GIRKO) develop diabetes and insulin-resistant AT with morphological changes of BAT (i.e., increased lipid droplet size and striking disruption of the multilocular structure) and heterogeneity of WAT [107], suggesting that the impaired insulin-induced glucose disposal derived from INSR deficiency differently affects the sensitivity of specific insulin-sensitive tissues.