Circadian gene Clock regulates mitochondrial morphology and functions by posttranscriptional way

Abstract Many daily activities are under the control of circadian clock, including nutrition metabolism and energy generation. Mitochondria, as the core factories of oxidizing substrates and producing ATP, undergo changes in quantity and morphology to adapt to the demand for energy. It has been demonstrated that mitochondrial gene expression, dynamics and functions are all affected by circadian clock. Here, we demonstrated that circadian gene Clock affects the number, architecture and function of mitochondria via posttranscriptional regulation of Drp1. Clock Δ19 leads to fragmented mitochondria accompanied with the loss of membrane potential, excessive ROS accumulation and decreased mitochondrial respiration and ATP generation. Clock Δ19 mice exhibit disordered lipid metabolism and evident nonalcoholic fatty liver disease (NAFLD), which are rescued by treatment with the mitochondrial fission inhibitor Mdivi-1. These results suggest a strong relationship between Clock, mitochondrial dynamics and metabolic diseases and provide a new perspective on disordered circadian clock and related diseases.