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We have previously developed a 3D video tracking system which enables us to analyze long-term quantitative analysis of gene expression in freely moving mice. In the present study, we improved 3D video tracking and developed a system that analyzes more detailed behavioral data. We succeeded in simultaneously analyzing sleep-wake, feeding, and drinking behavior rhythms in the same individual using our tracking system. This system will make it possible to measure gene expression in each tissue in vivo in real time in relation to the various behavioral rhythms mentioned above. • We developed 3D video tracking system to analyze the behavior in real time. • Our system can simultaneously measure three different behavioral rhythms in the same animal. • Our system will be useful for measuring gene expression that changes with behavioral rhythms. [ABSTRACT FROM AUTHOR]

Loss of CRY2 confers aggressive phenotypes to breast cancer. However, the mechanism of its downregulation and its prognostic value in breast cancer are still not clear. Our data mining in TCGA breast cancer cohort (TCGA-BRCA) showed that the luminal A subtype of breast cancer had the highest CRY2 expression, while the basal-like subtype had the lowest CRY2 expression. The ER+ group had significantly higher CRY2 expression than the ER- group. Demethylation treatment using 5-AZA-dC significantly restored CRY2 expression in MDA-MB-231 and BT549 cells. Co-expression analysis in TCGA-BRCA showed a strong negative correlation between CRY2 and FOXM1 (Pearson's r = −0.62). FOXM1 overexpression in MCF-7 cells reduced CRY2 expression, while FOXM1 knockdown in MDA-MB-231 cells increased CRY2 expression. Demethylation significantly abrogated FOXM1 induced CRY2 suppression in MCF-7 cells. Bioinformatic scanning predicted a common FOXM1 binding site in CRY2 transcript 1 and transcript 2 promoter. The following studies confirmed that through binding with DNMT3b, FOXM1 can bind to CRY2 promoter and enhance methylation in this region. Univariate analysis based on Cox proportional hazards model and the following NPI and AOL adjusted studies in bc-GenExMiner 4.0 showed that high CRY2 expression was an independent indicator of reduced risk of metastatic relapse (MR) in ER+ breast cancer patients, but not in ER- breast cancer. With these findings, we infer that FOXM1 is a negative regulator of CRY2 in breast cancer via enhancing methylation in CRY2 promoter and its high expression is an independent predictor of favorable MR-free survival in ER+ breast cancer patients. [ABSTRACT FROM AUTHOR]

Abstract: The discovery of clock genes revealed the major molecular components responsible for circadian time-keeping in mammals, but the mechanism by which autonomic nervous system may control circadian rhythm and its relationship to metabolism is unclear. As the Cry1 and Cry2 genes are indispensable for molecular core oscillator function, we investigated autonomic nervous system activity and metabolism in Cry1 −/− Cry2 −/− mice. The mice were kept in a light–dark cycle, and showed normal circadian locomotor activities including feeding. However, the circadian rhythmicity of oxygen consumption, heart rate, and body temperature were abolished, suggesting hypermetabolism in these mice. Cry1 −/− Cry2 −/− mice also showed impaired glucose tolerance due to decreased insulin secretion. These results indicate that sympathetic neural activity in Cry1 −/− Cry2 −/− mice is elevated, reducing adiposity and impairing insulin secretion and suggest that dysregulation of the autonomic nervous system may induce metabolic disorders. [Copyright &y& Elsevier]

Abstract: In mammals, behavioral and physiological processes display 24-h rhythms that are regulated by a circadian system. In the present study, we investigated the possibility that the expression of clock genes in peripheral leukocytes can be used to assess the circadian clock system. We found that Per1 and Per2 exhibit circadian oscillations in mRNA expression in mouse peripheral leukocytes. Furthermore, the rhythms of Per1 and Per2 mRNA expression in peripheral leukocytes are severely blunted in homozygous Cry1/2 double-deficient mice that are known to have an abolished biological clock. We have examined the circadian expression of clock genes in human leukocytes and found that Per1 mRNA exhibits a robust circadian expression while Per2 and Bmal1 mRNA showed weak rhythm. These observations suggest that monitoring Per1 mRNA expression in human leukocytes may be useful for investigating the function of the circadian system in physiological and pathophysiological states. [Copyright &y& Elsevier]