Mariko Izumo

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Mammalian cells such as rat-1 fibroblasts have been shown to exhibit daily oscillations in the expression of several gene transcripts in culture. After induction, these oscillations persist with a period of approximately 24 h for several days. This characteristic suggests that the oscillations are controlled by a circadian clock, but the crucial criterion(More)
The central circadian pacemaker is located in the hypothalamus of mammals, but essentially the same oscillating system operates in peripheral tissues and even in immortalized cell lines. Using luciferase reporters that allow automated monitoring of circadian gene expression in mammalian fibroblasts, we report the collection and analysis of precise rhythmic(More)
Circadian behavior in mammals is orchestrated by neurons within the suprachiasmatic nucleus (SCN), yet the neuronal population necessary for the generation of timekeeping remains unknown. We show that a subset of SCN neurons expressing the neuropeptide neuromedin S (NMS) plays an essential role in the generation of daily rhythms in behavior. We demonstrate(More)
BACKGROUND An interlocked transcriptional-translational feedback loop (TTFL) is thought to generate the mammalian circadian clockwork in both the central pacemaker residing in the hypothalamic suprachiasmatic nuclei and in peripheral tissues. The core circadian genes, including Period1 and Period2 (Per1 and Per2), Cryptochrome1 and Cryptochrome2 (Cry1 and(More)
Most laboratory mouse strains including C57BL/6J do not produce detectable levels of pineal melatonin owing to deficits in enzymatic activity of arylalkylamine N-acetyltransferase (AANAT) and N-acetylserotonin O-methyl transferase (ASMT), two enzymes necessary for melatonin biosynthesis. Here we report that alleles segregating at these two loci in C3H/HeJ(More)
In order to assess the contribution of a central clock in the hypothalamic suprachiasmatic nucleus (SCN) to circadian behavior and the organization of peripheral clocks, we generated forebrain/SCN-specific Bmal1 knockout mice by using floxed Bmal1 and pan-neuronal Cre lines. The forebrain knockout mice showed >90% deletion of BMAL1 in the SCN and exhibited(More)
mutant Bmal1 Differential effects of light and feeding on circadian organization of peripheral clocks in a forebrain Sato, Xiaozhong Wang, Christopher A Bradfield, Joseph S Takahashi Mariko Izumo, Martina Pejchal, Andrew C Schook, Ryan P Lange, Jacqueline A Walisser, Takashi R http://dx.doi.org/10.7554/eLife.04617 DOI: Cite as: eLife(More)
References and Notes 1. J. C. Dunlap, Cell 96, 271 (1999). 2. Y. Ouyang, C. R. Andersson, T. Kondo, S. S. Golden, C. H. Johnson, Proc. Natl. Acad. Sci. U.S.A. 95, 8660 (1998). 3. A. N. Dodd et al., Science 309, 630 (2005). 4. S. L. Harmer, S. Panda, S. A. Kay, Annu. Rev. Cell Dev. Biol. 17, 215 (2001). 5. C. R. McClung, Plant Cell 18, 792 (2006). 6. A. N.(More)
Prepared movements are more efficient than those that are not prepared for. Although changes in cortical activity have been observed prior to a forthcoming action, the circuits involved in motor preparation remain unclear. Here, we use in vivo two-photon calcium imaging to uncover changes in the motor cortex during variable waiting periods prior to a(More)
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