FIG. 5.
The circadian oscillator drives a mitochondrial fusion/fission cycle: a comparison of conditions at circadian minima and maxima of NAD+ levels, O2 consumption, and ATP synthesis. Enhanced fission is associated with low, prevailing fusion with high O2 consumption and ATP formation. ΔΨmt, mitochondrial membrane potential; AMPK, adenosine 5′-monophosphate-dependent protein kinase; DRP1/pDRP1, dynamin-related protein 1/phosphorylated dynamin-related protein 1; Fis1, mitochondrial fission 1 protein; LKB1/acLKB1, liver kinase B1/acetylated liver kinase B1 (LKB1 is part of the AMPKK complex); Mff, mitochondrial fission factor; mt, mitochondrial; PATs, protein acetyltransferases; PPases, protein phosphatases.