Helix-loop-helix Protein Id2 Stabilizes Mammalian Circadian Oscillation Under Constant Light Conditions

作     者：Adachi, Akihito A. Fujioka, Atsuko Nagano, Mamoru Masumoto, Koh-hei Takumi, Toru Yoshimura, Takashi Ebihara, Shizufumi Mori, Kentaro Yokota, Yoshifumi Shigeyoshi, Yasufumi 

作者机构：Kinki Univ Dept Anat & Neurobiol Sch Med Osaka 5898511 Japan RIKEN Brain Sci Inst Lab Mental Biol Wako Saitama 3510198 Japan Nagoya Univ Grad Sch Bioagr Sci Physiol Anim Lab Dept Appl Mol BiosciChikusa Ku Nagoya Aichi 4648601 Japan Nagoya Univ Grad Sch Bioagr Sci Div Biomodeling Chikusa Ku Nagoya Aichi 4648601 Japan Univ Fukui Div Mol Genet Dept Biochem & Bioinformat Sci Fac Med Sci Fukui 9101193 Japan 

出 版 物：《ZOOLOGICAL SCIENCE》 (动物科学)

年 卷 期：2013年第30卷第12期

页      面：1011-1018页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 071002[理学-动物学] 

基　　金：High Tech Research Center Japanese Ministry of Education Grants-in-Aid for Scientific Research [24790194, 23590290] Funding Source: KAKEN 

主　　题：circadian rhythm Id2 Per1 basic helix-loop-helix constant light conditions 

摘      要：The mammalian circadian oscillator is composed of interacting positive and negative transcription events. The clock proteins PER1 and PER2 play essential roles in a negative limb of the feedback loop that generates the circadian rhythm in mammals. In addition, the proteins CLOCK and BMAL1 (also known as ARNTL) form a heterodimer that drives the Per genes via the E-box consensus sequences within their promoter regions. In the present study, we demonstrate that Id2 is involved in stabilization of the amplitudes of the circadian oscillations by suppressing transcriptional activation of clock genes Clock and Bmal1. Id2 shows dynamic oscillation in the SCN, with a peak in the late subjective night. Under constant dark conditions (DD), Id2(-/-) mice showed no apparent difference in locomotor activity, however, under constant light conditions (LL), Id2(-/-) mice exhibit aberrant locomotor activity, with lower circadian oscillation amplitudes, although the free running periods in Id2(-/-) mice show no differences from those in either wild type or heterozygous mice. Id2(-/-) animals also exhibit upregulation of Per1 in constant light, during both the subjective night and day. In wild type mice, Id2 is upregulated by constant light exposure during the subjective night. We propose that Id2 expression in the SCN contributes to maintenance of dynamic circadian oscillations.