Rhythmic expression of DEC1 and DEC2 in peripheral tissues: DEC2 is a potent suppressor for hepatic cytochrome P450s opposing DBP

@article{Noshiro2004RhythmicEO,
  title={Rhythmic expression of DEC1 and DEC2 in peripheral tissues: DEC2 is a potent suppressor for hepatic cytochrome P450s opposing DBP},
  author={Mitsuhide Noshiro and Takeshi Kawamoto and Masae Furukawa and Katsumi Fujimoto and Yuzo Yoshida and Eri Sasabe and Shinichi Tsutsumi and Taizo Hamada and Sato Honma and Ken-ichi Honma and Yukio Kato},
  journal={Genes to Cells},
  year={2004},
  volume={9}
}
The mammalian master molecular clock consisting of several clock gene products in the suprachiasmatic nucleus (SCN) drives circadian rhythms in behaviour and physiology. Molecular clocks consisting of the same components also exist in various peripheral organs. DEC1 and DEC2, basic helix-loop-helix transcription factors, were recently reported to be involved in the central clock in the SCN. We examined the expression profile of DEC1 and DEC2 in the periphery and their roles in the regulation of… 
Significant dissociation of expression patterns of the basic helix–loop–helix transcription factors Dec1 and Dec2 in rat kidney
TLDR
Observations suggest the existence of a glucocorticoid gating mechanism in the circadian expression of Dec1 in rat kidney under a normal light–dark (LD) cycle.
Tissue-Specific Disruption of Rhythmic Expression of Dec1 and Dec2 in Clock Mutant Mice
TLDR
Significant changes in the Dec1 and Dec2 expression, as well as in the Per2, Dbp, and Npas2 expression in the periphery by Clock mutation, indicated that CLOCK plays a major role in the expression of these genes in most tissues, however, circadian expression of Dec1 in liver and kidney and that of Dec2 in skeletal muscle of Clock mutant mice suggested that CLock-independent circadian regulation operates in some tissues.
Liver X receptors (LXRα and LXRβ) are potent regulators for hepatic Dec1 expression
TLDR
Observations indicate that hepatic DEC1 mediates the ligand‐dependent LXR signal to regulate the expression of genes involved in the hepatic clock system and metabolism.
Expression of the gene for Dec2, a basic helix-loop-helix transcription factor, is regulated by a molecular clock system.
TLDR
It is shown that transcription of the Dec2 gene is regulated by several clock molecules and a negative-feedback loop, and that the Clock/Bmal heterodimer enhances Dec2 transcription via the CACGTG E-boxes, whereas the induced transcription is suppressed by Dec2, which therefore must contribute to its own rhythmic expression.
Rhythmic expression of DEC2 protein in vitro and in vivo.
TLDR
The results showed that the phosphorylation of AMPK immunoreactivity was strongly detected in the liver and lung of DEC2 knockout mice compared with that of wild-type mice, which may provide new insights into rhythmic expression and the regulation between DEC2 protein and AMPK activity.
Circadian Rhythm: A Functional Connection Between SHP and DEC1 Transcription Factor
TLDR
It is established that DEC1 constitutes the negative loop of the SHP oscillating expression and that the DEC1-SHP pathway is intimately involved in energy homeostasis with profound pathophysiologic significance.
Regulation of basic helix‐loop‐helix transcription factors Dec1 and Dec2 by RORα and their roles in adipogenesis †
TLDR
Examination of expression of Rorα, Dec1, Dec2 and other clock‐controlled genes in differentiating 3T3‐L1 adipocytes suggested that RORα suppresses adipogenic differentiation at a later stage of differentiation by RORE‐mediated stimulation of Dec1 and Dec2 expression.
DEC1 Modulates the Circadian Phase of Clock Gene Expression
TLDR
It is suggested that DEC1, along with DEC2, plays a role in the finer regulation and robustness of the molecular clock.
Arg in the bHLH transcription factor DEC 2 is essential for the suppression of CLOCK / BMAL 2-mediated transactivation
TLDR
It is demonstrated that 57Arg in the basic region of DEC2 is essential for its activity in suppressing CLOCK/BMAL2-mediated transactivation.
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