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Dentin et al. (2007) showed in mice that insulin inhibits gluconeogenic gene expression during refeeding by promoting the phosphorylation and ubiquitin-dependent degradation of TORC2. Insulin disrupts TORC2 activity by induction of the serine-threonine kinase SIK2, which the authors showed undergoes AKT2-mediated phosphorylation at ser358. Activated SIK2 in turn stimulated the ser171 phosphorylation and cytoplasmic translocation of TORC2. Phosphorylated TORC2 was degraded by the 26S proteasome during refeeding through an association with COP1 (608067), a substrate receptor for an E3 ligase complex that promoted TORC2 ubiquitination at lys628. Because TORC2 protein levels and activity were increased in diabetes owing to a block in TORC2 phosphorylation, Dentin et al. (2007) concluded that their results pointed to an important role for this pathway in the maintenance of glucose homeostasis.