Reduced C/EBPβ-LIP translation improves metabolic health.

Inactivation of target of rapamycin complex 1 (TORC1) signaling is considered important for the beneficial effects of caloric restriction (CR) on metabolism and health span. It is however not fully elucidated which cellular processes downstream of TORC1 are the main regulators of metabolic health. In this issue of EMBO Reports, Zidek et al [1] describe that inhibition of mammalian TORC1 (mTORC1) leads to decreased translation of CCAAT/ enhancer-binding protein b (C/EBPb)-liver inhibitory protein (LIP). Moreover, loss of C/EBPb-LIP in mice improves metabolic health, similar to the effects of CR. Zidek et al [1] thus report that reduced C/EBPb-LIP translation is a novel mTORC1-regulated process that could play a major role in mediating the beneficial metabolic effects of caloric restriction.