Publication Date:
2009-03-17
Description:
Many metabolic and physiological processes display circadian oscillations. We have shown that the core circadian regulator, CLOCK, is a histone acetyltransferase whose activity is counterbalanced by the nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylase SIRT1. Here we show that intracellular NAD+ levels cycle with a 24-hour rhythm, an oscillation driven by the circadian clock. CLOCK:BMAL1 regulates the circadian expression of NAMPT (nicotinamide phosphoribosyltransferase), an enzyme that provides a rate-limiting step in the NAD+ salvage pathway. SIRT1 is recruited to the Nampt promoter and contributes to the circadian synthesis of its own coenzyme. Using the specific inhibitor FK866, we demonstrated that NAMPT is required to modulate circadian gene expression. Our findings in mouse embryo fibroblasts reveal an interlocked transcriptional-enzymatic feedback loop that governs the molecular interplay between cellular metabolism and circadian rhythms.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Nakahata, Yasukazu -- Sahar, Saurabh -- Astarita, Giuseppe -- Kaluzova, Milota -- Sassone-Corsi, Paolo -- R01-GM081634/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2009 May 1;324(5927):654-7. doi: 10.1126/science.1170803. Epub 2009 Mar 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmacology, School of Medicine, University of California, Irvine, Irvine, CA 92697, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19286518" target="_blank"〉PubMed〈/a〉
Keywords:
ARNTL Transcription Factors
;
Acrylamides/pharmacology
;
Animals
;
Basic Helix-Loop-Helix Transcription Factors/metabolism
;
Biological Clocks
;
CLOCK Proteins
;
Cell Line
;
Chromatin Assembly and Disassembly
;
*Circadian Rhythm
;
Cytokines/antagonists & inhibitors/genetics/*metabolism
;
Enzyme Inhibitors/pharmacology
;
*Feedback, Physiological
;
*Gene Expression Regulation
;
Male
;
Mice
;
Mice, Inbred BALB C
;
Mice, Knockout
;
NAD/*metabolism
;
Niacinamide/metabolism
;
Nicotinamide Phosphoribosyltransferase/antagonists &
;
inhibitors/genetics/*metabolism
;
Piperidines/pharmacology
;
Promoter Regions, Genetic
;
Sirtuin 1
;
Sirtuins/*metabolism
;
Trans-Activators/genetics/*metabolism
;
Transcription, Genetic
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
