Circadian clock nad+ cycle drives mitochondrial oxidative metabolism in mice

Introduction: The circadian clock is a transcriptional oscillator that is thought to couple internal energetic processes with the solar cycle. Circadian oscillation in activity of nicotinamide phosphoribo-syltransferase (NAMPT), the rate-limiting enzyme in nicotinamide adenine dinucleotide (NAD+) bio-synthesis, feeds back to regulate activity of the deacetylase SIRT1 and transcription of genes encoding core clock components. Despite evidence that NAD+-dependent enzymes are important in fasting an