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Understanding the molecular genetic basis of animal magnet reception has been one of the big challenges in biology. Recently it was discovered that the magnetic sense of Drosophila melanogaster is mediated by the ultraviolet (UV)-A/blue light photoreceptor cryptochrome (Cry).Here, using the fruit fly as a magnet receptive model organism, we show that exposure to a specific AC magnetic field during night time affected the health of the fly. AC magnetic field exposure showed lifespan extension under starvation, sleep improvement and prevention of decreased motor function. In contrast, all the health improvement effect was not observed in cryptochrome mutant flies (cryb). We showed that AC magnetic field exposure prevented motor dysfunction in Gaucher’s disease model Drosophila. The data suggests that magnetic field-dependent improvement of sleep quality, lifespan and motor function is mediated through a cry-dependent pathway in animals.

Sleep in Drosophila was defined in the year 2000 by using Drosophila Activity Monitor (DAM) system. But DAM is very small tube space and one fly per tube is very limited to analyze for fly social behavior. To overcome such demerits of DAM system, we developed a novel automated sleep and rhythm analysis system (AutoCircaS) which monitors and records any behaviors like social mating, sleep, and circadian rhythm in flies (Drosophila) and small fishes medaka (Oryzias latipes) in free space using the time-lapse (one frame per 10 sec) imaging. AutoCircaS can detect the caffeine-induced insomnia in flies in light-dark (LD) and constant dark (DD) conditions. Thus, using the AutoCircaS, we discovered that Japanese traditional herbal medicines, KyushinKannouGan-ki (KKG), NouKassei (NK) as well as, and Sansoninto, significantly improved caffeine-induced insomnia in flies. The data suggest that AutoCircaS is useful for sleep analysis of small animals and screening of new sedative-hypnotics from many origins.

A circadian rhythm is a roughly 24-h cycle in biological processes and physiological phenomena such as sleep, feeding, and photosynthesis for many organisms on Earth. The circadian patterns are coordinated by rhythmical gene expression of clock genes. Time-course transcriptomic analyses involving statistical methods have shown coordination of periodic gene expression in many organisms. Here we applied the cosine fitting method COSOPT to identify novel oscillating genes in microarray data for the chordate Ciona intestinalis. This organism showed rhythmic oxygen consumption in our previous study, but there were few homologous clock genes showing rhythmic mRNA expression. To understand circadian behavior at the transcriptomic level, we analyzed the 817 of 21,938 probes showing a 23- to 25-h period by means of COSOPT. Coupling the analysis of period detection with functional annotations indicated that previously unknown rhythmic mRNA expression might exist in C. intestinalis. In addition, we are releasing our implementation of COSOPT by means of R and C. All source code and supplementary information are available from https://github.com/mhiromi/cosopt .

Parkinson's disease (PD) is a common neurodegenerative disorder with motor symptoms linked to the loss of dopaminergic neurons in the brain. α-Synuclein is an aggregation-prone neural protein that plays a role in the pathogenesis of PD. In our previous paper, we found that saffron; the stigma of Crocus sativus Linne (Iridaceae), and its constituents (crocin and crocetin) suppressed aggregation of α-synuclein and promoted the dissociation of α-synuclein fibrils in vitro. In this study, we investigated the effect of dietary saffron and its constituent, crocetin, in vivo on a fly PD model overexpressing several mutant α-synuclein in a tissue-specific manner. Saffron and crocetin significantly suppressed the decrease of climbing ability in the Drosophila overexpressing A30P (A30P fly PD model) or G51D (G51D fly PD model) mutated α-synuclein in neurons. Saffron and crocetin extended the life span in the G51D fly PD model. Saffron suppressed the rough-eyed phenotype and the dispersion of the size histogram of the ocular long axis in the eye of A30P fly PD model. Saffron had a cytoprotective effect on a human neuronal cell line with α-synuclein fibrils. These data showed that saffron and its constituent crocetin have protective effects on the progression of PD disease in animals in vivo and suggest that saffron and crocetin can be used to treat PD.

Parkinson’s disease (PD) is a common neurodegenerative disorder with motor symptoms linked to the loss of dopaminergic neurons in the brain. α-Synuclein is an aggregation-prone neural protein that plays a role in the pathogenesis of PD. In our previous paper, we found that saffron; the stigma of Crocus sativus Linné (Iridaceae), and its constituents (crocin and crocetin) suppressed aggregation of α-synuclein and promoted the dissociation of α-synuclein fibrils in vitro. In this study, we investigated the effect of dietary saffron and its constituent, crocetin, in vivo on a fly PD model overexpressing several mutant α-synuclein in a tissue-specific manner. Saffron and crocetin significantly suppressed the decrease of climbing ability in the Drosophila overexpressing A30P (A30P fly PD model) or G51D (G51D fly PD model) mutated α-synuclein in neurons. Saffron and crocetin extended the life span in the G51D fly PD model. Saffron suppressed the rough-eyed phenotype and the dispersion of the size histogram of the ocular long axis in A30P fly PD model in eye. Saffron had a cytoprotective effect on a human neuronal cell line with α-synuclein fibrils. These data showed that saffron and its constituent crocetin have protective effects on the progression of PD disease in animals in vivo and suggest that saffron and crocetin can be used to treat PD.

Although electric fields (EF) exert beneficial effects on animal wound healing and differentiation, the molecular mechanisms of these effects have remained unclear for years. Therefore, we aimed to elucidate the molecular mechanisms underlying these effects in Drosophila melanogaster as a genetic animal model. The sleep quality of wild-type (WT) flies was improved by exposure to a 50-Hz (35 kv/m) constant electric field during the daytime, but not during the night. This effect was undetectable in Cryptochrome mutant (Cryb) flies. Exposure to a 50-Hz electric field under low nutrient conditions elongated the lifespan of male and female WT flies by ~18%, but not of three diferrent Cry mutants and Cry RNAi strains. Metabolome analysis indicated that the adenosine triphosphate (ATP) content was 5-fold higher in intact WT than Cry gene mutant strains exposed to an electric field.A putative magnetoreceptor protein and UV-A/blue light photoreceptor, CRYPTOCHROME (CRY) is involved in electric field receptors in animals. The present findings constitute hitherto unknown genetic evidence of a CRY-based system that is electric-field sensitive in animals.

Accumulating evidence indicates that the molecular circadian clock underlies the mating behavior of Drosophila melanogaster. However, information about which gene affects circadian mating behavior is poorly understood in animals. The present study found that feeding Myo-inositol enhanced the close-proximity (CP) rhythm of D. melanogaster mating behavior and lengthened the period of the CP rhythm. Then, to understand a role for inositol synthesis to fly mating behavior, we established the Inos (Myo-inositol 1-phosphate synthase) gene knock down fly strains with RNAi. Interestingly, the CP behavior of this three-different driver knock down strains was arrhythmic, but the locomotor rhythm was rhythmic. The data of three-different Inos knock down strains suggests that Inos gene expression of upper LNd, l-LNV, 5ths-LNv in brain is necessary for proper CP rhythm generation in D. melanogaster. The data indicated that the Inos gene is involved in the role for the circadian rhythm of D. melanogaster mating behavior.

Gaucher's disease in humans is considered a deficiency of glucocerebrosidase (GlcCerase) that result in the accumulation of its substrate, glucocerebroside (GlcCer). Although mouse models of Gaucher's disease have been reported from several laboratories, these models are limited due to the perinatal lethality of GlcCerase gene. Here, we examined phenotypes of Drosophila melanogaster homologues genes of the human Gaucher's disease gene by using Minos insertion. One of two Minos insertion mutants to unknown function gene (CG31414) accumulates the hydroxy-GlcCer in whole body of Drosophila melanogaster. This mutant showed abnormal phenotypes of climbing ability and sleep, and short lifespan. These abnormal phenotypes are very similar to that of Gaucher's disease in human. In contrast, another Minos insertion mutant (CG31148) and its RNAi line did not show such severe phenotype as observed in CG31414 gene mutation. The data suggests that Drosophila CG31414 gene mutation might be useful for unraveling the molecular mechanism of Gaucher's disease.

Directed evolution is a very popular strategy for improving biophysical properties and even for generating proteins with novel functions. Recent advances in combinatorial protein engineering mean it is now possible to develop protein scaffolds that could substitute for whole antibody-associated properties as emerging therapeutic proteins. In particular, disulfide-rich proteins are attractive templates for directed evolution in the search for novel molecules because they can regulate the activities of receptors, enzymes, and other molecules. Previously, we demonstrated that functional regulatory molecules against interleukin-6 receptor (IL-6R) could be obtained by directed evolution of the three-finger toxin (3F) scaffold. In the present study, trypsin was selected as a target for directed evolution to further explore the potential use of the 3F cDNA display library. After seven rounds of selection, the DNA sequences converged. The recombinant proteins produced by the selected candidates had inhibitory activity against trypsin (Ki of 33-450 nM). Three of the six groups had Ki values that were comparable to bovine pancreatic trypsin inhibitor and soybean trypsin inhibitor. Two of the candidates also had inhibitory effects against chymotrypsin and kallikrein. This study suggests that 3F protein is suitable for the preparation of high-diversity libraries that can be utilized to obtain protease inhibitors. In addition to our previous successful targeting of IL-6R, the technique developed in our studies may have wide applications in the generation of regulatory molecules for targets of interest, such as receptors, enzymes for research, diagnostic applications, and therapeutic uses.

Mood disorders are considered to be associated with altered circadian rhythms, but the correlation between them has remained obscure. The mood stabilizer, lithium, is an inhibitor of glycogen synthase kinase-3β (GSK-3β), which is a modulator of the circadian clock system. Here, we show that chronic restraint (CR) stress diminishes behavioral activity and rhythmicity in mice. CR stress elevated GSK-3β phosphorylation and blunted the rhythmic expression of PERIOD2 (PER2) in the brain. Moreover, lithium, when administered to the stress-imposed mice, reduced GSK-3β phosphorylation and restored PER2 expression in the suprachiasmatic nucleus in a nighttime-specific manner. These data suggest that CR stress altered the circadian behavioral rhythm through a change in circadian gene expression of PER2 and GSK-3β phosphorylation in the suprachiasmatic nucleus.

Circadian clocks of Drosophila melanogaster motivate males to court females at a specific time of day. However, clock neurons involved in courtship rhythms in the brain of Drosophila remain totally unknown. The circadian locomotor behavior of Drosophila is controlled by morning (M cells) and evening (E cells) cells in the brain, which regulate morning and evening activities, respectively. Here, we identified the brain clock neurons that are responsible for the circadian rhythms of the close-proximity (CP) behavior that reflects male courtship motivation. Interestingly, the ablation or functional molecular clock disruption of E cells caused arrhythmic CP behavior, but that of M cells resulted in sustained CP rhythms even in constant darkness. In addition, the ablation of some dorsal lateral neurons (LNd) of E cells using neuropeptide-F (NPF)-GAL4 did not impair CP rhythms. These findings suggested that the NPF-negative LNds and DN1s of E cells include cells essential for circadian CP behavior in Drosophila.

Dietary compounds influence the expression of various genes and play a major role in changing physiological and metabolic states. However, little is known about the role of food ingredients in the regulation of circadian gene expression. Here, we show that feeding mice with a high-salt (HS) diet ad libitum for over 2weeks advanced the phase of clock gene expression by about 3h in the liver, kidney, and lung, but did not change circadian feeding, drinking, and locomotor rhythms. Focused DNA microarray analysis showed that the expression phase of many genes related to metabolism in the liver was also advanced. Immediately before phase advancement in peripheral tissues, the mRNA expression of sodium-glucose cotransporter 1 (Sglt1) and glucose transporter 2 (Glut2), that are responsible for glucose absorption, was increased in the jejunum. Furthermore, blood glucose uptake increased more rapidly after consuming the HS diet than the control diet. Moreover, phloridzin, a specific inhibitor of SGLT1, prevented the increased glucose transporter expression in the jejunum and phase advancement in the livers of mice on the HS diet. These results suggest that increased glucose absorption induced by dietary HS alters the food entrainment of peripheral molecular circadian rhythms.

Some reports have indicated that the core clock gene, Per2 regulates the cell cycle, immune system and neural functions. To understand the effects of PER2 on tumor growth in vivo, stable transformants of murine sarcoma 180 (S-180) cell lines expressing different levels of PER2 were established. The growth of stable PER2 transformants in vivo was significantly and dose-dependently suppressed according to the amount of PER2 expressed, indicating that PER2 plays a role in the growth suppression of sarcoma cells. The anchorage-dependent and -independent growth in vitro and expression of the clock controlled cell-cycle related genes, wee1, myc, and VEGF were not altered in stable PER2 transformants. In contrast, susceptibility to murine natural killer (NK) cell cytolytic activity was enhanced in PER2 transformants. Furthermore, PER2 transformants suppressed cell motility and reduced fibronectin expression, but the expression of integrin receptors was not affected. These results suggest that sarcoma cells overexpressing PER2 suppress tumors in vivo by changing the nature of tumor cell adhesion.

The molecular mechanisms of the endogenous circadian clocks that allow most animals to adapt to environmental cycles have recently been uncovered. The draft genome of the ascidian, Ciona intestinalis, a model animal that is close to vertebrates, has been described. However, the C. intestinalis genome lacks the canonical clock genes such as Per, Bmal and Clock that are shared by vertebrates and insects. Here, we found the circadian rhythms at the physiological and molecular levels. The oxygen consumption rate was lower during the light phase and higher during the dark phase during a day, and the rhythm highly damped and continued under constant darkness. From the microarray analysis, the 396 spots (1.8% of the total; corresponding to 388 clones) were extracted as candidates for circadian expression. We confirmed the circadian expression of several candidate genes by northern blotting. Furthermore, three of four rhythmic expressed genes showed phase-shifts to prolonged light period. However, most of known clock genes did not oscillate. These data suggest that C. intestinalis have a unique molecular circadian clock and the daily environmental change is not such a strong effect for sea squirt in its evolution when compared to vertebrates and insects.

In nature, hibernating animals experience fasting, cold temperature, and short day seasonally. Torpor is a state of decreased physiological activity in an animal, usually characterized by a reduced body temperature and rate of metabolism to adapt to such a severe environment. Ablation of the central clock synchronizer, the suprachiasmatic nucleus in brain, abolishes torpor, a hibernation-like state, implicating the circadian clock involved in this seasonal change. Biologists know well that the energy source of daily heterotherms/hibernators change from glucose to lipids in winter. Here we review several lines of evidence of a master transcriptional regulator in lipid catabolism, peroxisome proliferator-activated receptor α (PPARα), in the control of torpor through the fibroblast growth factor 21—neuropeptide Y (FGF21—NPY) pathway.1 Furthermore, we showed the role of PERIOD2 protein as a suppressor of plasminogen activator inhibitor-1(PAI-1) gene expression using PER2 transgenic mice. These indicates the importance of clock genes to tell seasons to improve and cardiovascular function.

Circadian clock genes play a role for the regulation of cell cycle, but the factors connecting clock to cell cycle are not fully understood. We found that mRNA of Kid-1--a zinc-finger-type transcriptional repressor was localized to cortical and juxtamedullary segments of tubules but not to glomeruli in the rat kidney. Kid-1 mRNA showed robust circadian oscillation with a peak at ZT16. Under temporal restricted feeding, the phase of the oscillation shifted along with mRNAs of the clock genes--Per1 and Per2. The rhythm of S-phase in cell cycle disappeared in the kidney under the restricted feeding. The level of phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was rhythmic with a peak at ZT16 in the kidney. We found that knockdown and overexpression of Kid-1 in NRK52E (normal rat kidney epithelial) cells induced and reduced the phosphorylation of ERK1/2, respectively. The data suggest that clock-controlled Kid-1 regulates the cell cycle of proliferating renal tubular epithelial cells through ERK phosphorylation.

In mammals, circadian genes, Clock, Arntl (also known as Bmal1), Cry1, Cry2, Per1, Per2, and Per3, are rhythmically transcribed every 24 h in almost all organs and tissues to tick the circadian clock. However, their expression and function in oocytes and preimplantation embryos have not been investigated. In this study we found that the circadian clock may stop in mouse oocytes and preimplantation embryos. Real-time PCR analysis revealed the presence of transcripts of these genes in both oocytes and preimplantation embryos; however, their amounts did not oscillate every 24 h in one- to four-cell and blastocyst-stage embryos. Moreover, immunofluorescence analyses revealed that CLOCK, ARNTL, and CRY1 were localized similarly in the nuclei of germinal vesicle (GV) oocytes and one-cell- to four-cell-stage embryos. Because CRY1 is known to interact with the CLOCK-ARNTL complex to suppress transcription-promoting activity of the complex for genes such as Wee1, Cry2, Per1, Per2, and Per3 in cells having the ticking circadian clock, we hypothesized that if the circadian clock functions in GV oocytes and one-cell- to four-cell-stage embryos, CLOCK, ARNTL, and CRY1 might suppress the transcription of these genes in GV oocytes and one-cell- to 4-cell-stage embryos as well. As a result, knockdown of CRY1 in GV oocytes by RNA interference did not affect the transcription levels of Wee1, Cry2, Per1, Per2, and Per3, but it reduced maturation ability. Thus, it seems that circadian genes are not involved in circadian clock regulation in mouse oocytes and preimplantation embryos but are involved in physiologies, such as meiosis.

The circadian clock comprises transcriptional feedback loops of clock genes. Cryptochromes are essential components of the negative feedback loop in mammals as they inhibit CLOCK-BMAL1-mediated transcription. We purified mouse CRY1 (mCRY1) protein complexes from Sarcoma 180 cells to determine their roles in circadian gene expression and discovered that Myb-binding protein 1a (Mybbp1a) interacts with mCRY1. Mybbp1a regulates various transcription factors, but its role in circadian gene expression is unknown. We found that Mybbp1a functions as a co-repressor of Per2 expression and repressed Per2 promoter activity in reporter assays. Chromatin immunoprecipitation (ChIP) assays revealed endogenous Mybbp1a binding to the Per2 promoter that temporally matched that of mCRY1. Furthermore, Mybbp1a binding to the Per2 promoter correlated with the start of the down-regulation of Per2 expression and with the dimethylation of histone H3 Lys9, to which it could also bind. These findings suggest that Mybbp1a and mCRY1 can form complexes on the Per2 promoter that function as negative regulators of Per2 expression.

A regional evaluation of the soil organic carbon (SOC) dynamics for the chernozem zone in northern Kazakhstan is now vitally important for agricultural and environmental policy making. The objectives of the present study were: (1) to predict spatial and temporal variability in C input as crop residues using multi-temporal MODIS satellite images, (2) to clarify spatial and temporal variability in CO2 emission as SOC output using geostatistics and model s, (3) to clarify spatial and temporal variability in the SOC budget using the results from (1) and (2). The mean growing-season C input as plant residues in cereal fields ranged from 0.9 to 1.4 Mg C ha−1, with higher values in wet years. Carbon input as plant residues was higher in the northern part of the area than in the other parts. The average growing-season CO2 emission ranged from 0.9 to 1.1 Mg C ha−1, and was also higher in wet years than in dry years. In addition, more CO2 was emitted in the northern part of this area. Accordingly the avera...

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors belonging to the nuclear receptor family. PPARs play a critical role in lipid and glucose metabolism. We examined whether chronic treatment with bezafibrate, a PPAR agonist, would alter sleep and body temperature (BT). Mice fed with a control diet were monitored for BT, electroencephalogram (EEG), and electromyogram for 48 h under light-dark conditions. After obtaining the baseline recording, the mice were provided with bezafibrate-supplemented food for 2 wk, after which the same recordings were performed. Two-week feeding of bezafibrate decreased BT, especially during the latter half of the dark period. BT rhythm and sleep/wake rhythm were phase advanced about 2–3 h by bezafibrate treatment. Bezafibrate treatment also increased the EEG delta-power in nonrapid eye movement sleep compared with the control diet attenuating its daily amplitude. Furthermore, bezafibrate-treated mice showed no rebound of EEG delta-power in nonrapid eye movement sleep after 6 h sleep deprivation, whereas values in control mice largely increased relative to baseline. DNA microarray, and real-time RT-PCR analysis showed that bezafibrate treatment increased levels of Neuropeptide Y mRNA in the hypothalamus at both Zeitgeber time (ZT) 10 and ZT22, and decreased proopiomelanocortin-α mRNA in the hypothalamus at ZT10. These findings demonstrate that PPARs participate in the control of both BT and sleep regulation, which accompanied changes in gene expression in the hypothalamus. Activation of PPARs may enhance deep sleep and improve resistance to sleep loss.

Although Bmal1 is a key component of the mammalian clock system, little is understood about the actual mechanism of circadian Bmal1 gene transcription, particularly at the chromatin level. Here we discovered a unique chromatin structure within the Bmal1 promoter. The RORE region, which is a critical cis element for the circadian regulation of the Bmal1 gene, is comprised of GC-rich open chromatin. The 3'-flanking region of the promoter inhibited rhythmic transcription in the reporter gene assay in vitro even in the presence of RORalpha and REV-ERBalpha. We also found that the nuclear matrix protein SAF-A binds to the 3'-flanking region with circadian timing, which was correlated with Bmal1 expression by footprinting in vivo. These results suggest that the unique chromatin structure containing SAF-A is required for the circadian transcriptional regulation of the Bmal1 gene in cells.

To optimize regional crop rotation systems to mitigate soil organic carbon (SOC) depletion, monitoring the spatial and temporal variation of the SOC budget is of major importance. This study evaluated the influence of crop rotation and topography on the spatial and temporal variation of the SOC budget under cereal cropping in northern Kazakhstan using a geostatistical method, predicted equations of CO2 emission and Moderate Resolution Imaging Spectroradiometer satellite images. The study was carried out in large-scale upland fields (7,915 ha) located in Shortandy, Aqmorinskaya Oblast, from 2001 to 2005. Under the assumption that all crop residue was incorporated into the soil, average annual C input as plant residues in cereal and abandoned fields ranged from 1.0 to 1.6 Mg C ha−1 year−1, with higher values in wet years. Average annual CO2 emission in the cereal fields and the fallow fields ranged from 1.0 to 1.2 Mg C ha−1 year−1 and from 0.7 to 0.8 Mg C ha−1 year−1, respectively. In relation to t...

Agricultural production in southern Kazakhstan has experienced significant economic difficulty since the 1980s, accelerating agronomic problems including the salinization of irrigated fields. A thorough understanding of the up-to-date situation of soil salinization and its effects on cropping systems is necessary in order to establish sustainable agricultural systems with avoiding land degradation for the region. This study examined the relationships between soil salinity, crop yield and affecting factors including local terrain for two farms. Both farms are characterised by a gentle slope, flat area and localised depressions. Most of the paddy fields showed wash-out of salts during the irrigation period except in waterlogged fields situated in depressions. Rice yield was adversely affected by the remaining soil salinity, deep ponding water and insufficient drainage capacity in the lower part of the irrigation system. Salt accumulation in the upland fields appeared to increase with cropping years, and was associated with groundwater depth that became shallower at the lower parts of the irrigation systems, adversely affecting the crop growth in most fields. Since the cropping patterns had recently changed in the region, each pattern was compared against the recommendation of this study. Most patterns were concluded to be potentially effective for preventing soil salinization if conducted under an optimum economic and social system. Copyright © 2007 John Wiley & Sons, Ltd.

Molecular circadian clock regulation engages a negative feedback loop comprising components of the negative limb, PERs and CRYs. In addition to the rhythmic transcriptional regulation of clock genes, controlled subcellular localization might contribute to the molecular mechanism of the mammalian circadian clock. To address this issue, we generated transgenic (TG) mice lines harboring either rat PER2 (rPER2) with a deleted nuclear localizing domain [NLD(–)] or intact PER2. In comparison with wild-type (WT) control, the period of the circadian locomotor rhythm in TG mice over-expressing NLD(–) PER2 was longer, while that in TG mice over-expressing intact PER2 was shorter. The nuclear entry of endogenous PER2, CRY1 and CRY2 was delayed in the suprachiasmatic nucleus (SCN) of NLD(–) PER2 TG mice under constant darkness, whereas that of mouse PER2 (mPER2) is accelerated in the SCN of intact PER2 TG mice. Under constant light, the locomotor activity of NLD(–) PER2 TG mice became arrhythmic, whereas WT animals remained rhythmic. These data indicate that PER2 controls circadian periods through nuclear localization in the SCN. In addition, sleep architecture was also affected in intact PER2 TG mice, suggesting PER2 can modulate a sleep molecular mechanism.

Cardiovascular diseases are closely related to circadian rhythm, which is under the control of an internal biological clock mechanism. Although a biological clock exists not only in the hypothalamus but also in each peripheral tissue, the biological relevance of the peripheral clock remains to be elucidated. In this study we searched for clock-controlled genes in vascular endothelial cells using microarray technology. The expression of a total of 229 genes was up-regulated by CLOCK/BMAL2. Among the genes that we identified, we examined the thrombomodulin (TM) gene further, because TM is an integral membrane glycoprotein that is expressed primarily in vascular endothelial cells and plays a major role in the regulation of intravascular coagulation. TM mRNA and protein expression showed a clear circadian oscillation in the mouse lung and heart. Reporter analyses, gel shift assays, and chromatin immunoprecipitation analyses using the TM promoter revealed that a heterodimer of CLOCK and BMAL2 binds directly to the E-box of the TM promoter, resulting in TM promoter transactivation. Indeed, the oscillation of TM gene expression was abolished in clock mutant mice, suggesting that TM expression is regulated by the clock gene in vivo. Finally, the phase of circadian oscillation of TM mRNA expression was altered by temporal feeding restriction, suggesting TM gene expression is regulated by the peripheral clock system. In conclusion, these data suggest that the peripheral clock in vascular endothelial cells regulates TM gene expression and that the oscillation of TM expression may contribute to the circadian variation of cardiovascular events.

This study aimed to improve the accuracy of spatial prediction for soil organic matter, potential mineralizable carbon (PMC) and soil organic carbon (SOC), using secondary information, namely topographic and vegetation information, in northern Kazakhstan. Secondary information included elevation (ELEV), mean curvature (MEANC), compound topographic index (CTI) and slope (SLOPE) obtained from a digital elevation model, and enhanced vegetation index (VI) values obtained from a moderate resolution imaging spectroradiometer (MODIS). The prediction methods were statistical (multiple linear regression between soil organic matter and secondary information) and geostatistical algorithms (regression-kriging Model-C and simple kriging with varying local means [SKlm]). The VI, ELEV and MEANC were selected as the independent variables for predicting PMC and SOC. However, MEANC showed an opposite effect on PMC and SOC accumulation patterns. Model validity revealed that SKlm was the most appropriate method for ...

The practice of monoculture land use without regard for local environmental conditions can accelerate organic matter decomposition. In the agriculturally and environmentally important soils of northern Kazakhstan, which primarily support cereal cultivation, economic rewards might encourage such monoculture practices. The purpose of this study was to clarify the influence of land use on the dynamics of soil organic carbon in situ for the three different soil classes, Dark Chestnut (DC), Southern Chernozem (SC) and Ordinary Chernozem (OC), in this region. Fluctuations in CO2 emission from the soils showed a similar pattern to temperature fluctuations. Land use markedly influenced the seasonal variation of CO2 emission, in particular fluctuations in CO2 sensitivity to soil temperature. To estimate daily CO2 emission, a prediction equation of CO2 emission using stepwise multiple regression of the Arrehenius model was derived from environmental soil factors by soil type and land use type. Using soil e...

The bZIP transcription factor E4BP4, is a mammalian homologue of vrille that functions as a key negative component of the circadian clock. We have shown that the E4BP4-binding site (B-site) is required in addition to a non-canonical E-box (E2 enhancer) for robust circadian Period2 (Per2) expression in the cell-autonomous clock. While the E2 enhancer and the B-site are closely situated, correlations between each component bound to the E2 enhancer and the B-site remain obscure. Here, we show that E4BP4 interacts with PER2, which represses transcriptional activity via the E-box enhancer. Interaction with PER2 required the carboxyl-terminal region that contains the repression domain of E4BP4. We also found that E4BP4 interacts with CRYPTOCHROME2 (CRY2), a key negative regulator in the mammalian circadian clock. These results suggest that E4BP4 is a component of the negative regulator complex of mammalian circadian clocks.

SummaryRelationships between energy intake and fibrinolytic functions have been documented in detail. We evaluated food deprivation (FD) as a means of modulating fibrinolytic activity in genetically obese and diabetic db/db mice and in their lean counterparts. Twelve hours of FD induced considerable gene expression of plasminogen activator inhibitor-1 (PAI-1) in both epididymal (3.8-fold, p

This study examined circadian variation in coagulation and fibrinolytic parameters among Jcl:ICR, C3H/HeN, BALB/cA, and C57BL/6J strains of mice. Plasma plasminogen activator inhibitor 1 (PAI-1) levels fluctuated in a circadian manner and peaked in accordance with the mRNA levels at the start of the active phase in all strains. Fibrinogen mRNA levels peaked at the start of rest periods in all strains, although plasma fibrinogen levels remained constant. Strain differences in plasma antithrombin (AT) activity and protein C (PC) levels were then identified. Plasma AT activity was circadian rhythmic only in Jcl:ICR, but not in other strains, although the mRNA levels remained constant in all strains. Levels of plasma PC and its mRNA fluctuated in a circadian manner only in Jcl:ICR mice, whereas those of plasma prothrombin, factor X, factor VII, prothrombin time (PT), and activated partial thrombin time (APTT) remained constant in all strains. These results suggest that genetic heterogeneity underlies phenotypic variations in the circadian rhythmicity of blood coagulation and fibrinolysis. The circadian onset of thrombotic events might be due in part to the rhythmic gene expression of coagulation and fibrinolytic factors. The present study provides fundamental information about mouse strains that will help to understand the circadian variation in blood coagulation and fibrinolysis.

Accumulating evidence indicates that the molecular circadian clock underlies the mating behavior of D. melanogaster. However, information about which food components affect circadian mating behavior is scant. The ice plant, Mesembryanthemum crystallinum has recently become a popular functional food. Here, we showed that the close-proximity (CP) rhythm of Drosophila melanogaster courtship behavior was damped under low-nutrient conditions, but significantly enhanced by feeding the flies with powdered ice plant. Among various components of ice plants, we found that myo-inositol increased the amplitude and slightly shortened the period of the CP rhythm. Real-time reporter assays showed that myo-inositol and D-pinitol shortened the period of the circadian reporter gene Per2-luc in NIH 3T3 cells. These data suggest that the ice plant is a useful functional food and that the ability of inositols to shorten rhythms is a general phenomenon in insects as well as mammals.

A central circadian clock located in the suprachiasmatic nucleus (SCN) of the mammalian hypothalamus entrains peripheral clocks through both neural and humoral factors. Although candidates for entrainment factors have been described, their details remain obscure. Here, we screened ligands for nuclear receptors that affect CLOCK/BMAL1-dependent transactivation of the mouse Period1 (mPer1) gene in NIH3T3 cells. We found that retinoic acids (RAs) significantly up-regulate mPer1 expression in an E-box-dependent manner. We also found that RAs up-regulate the expression of other E-box-dependent circadian genes such as mPer2, arginine vasopressin (mAVP), and peroxisome proliferator-activated receptor alpha (mPPARalpha). Surprisingly, the effect of RAs on CLOCK/BMAL1 (E-box)-dependent mRNA expression was bidirectional and depended on the presence of exogenous retinoic acid receptor alpha (RARalpha). These results suggest that RAs regulate the CLOCK/BMAL1-dependent transcription of circadian genes in a complex manner.

We observed the learning ability in Clock mutant mice with Jcl/ICR background (Clockj), a mice model of evening-type individuals, in the early part of dark phase. In order to estimate the learning ability, Morris water maze (WM) and passive avoidance (PA) test were performed. Release of acetylcholine, 5 hydroxytryptophan (5-HT) and dopamine (DA) in hippocampus was measured by in vivo microdialysis method. Clockj showed the impaired learning ability in the WM, but not in PA test. Hippocampal acetylcholine release was significantly attenuated in the Clockj in comparison to the wild-type mice. Neither 5-HT nor DA in the hippocampus was affected by the Clock mutation. Clock, an essential gene controlling circadian rhythm, may have an important role on the spatial learning and hippocampal cholinergic function, at least, at the beginning of the dark phase.

In mammals, circadian oscillators exist not only in the central clock of the suprachiasmatic nucleus (SCN) but also in peripheral tissues such as the liver, heart and kidneys. Peripheral clocks are entrained to the SCN clock by both neural and humoral signals. Vitamin A might be one candidate that synchronizes peripheral clocks by activating its ligand-dependent nuclear receptors in mammals. The present study examines the effect of a Vitamin A deficiency on the circadian expression of clock genes in the mouse liver. Serum Vitamin A levels remained constant throughout the day in control mice, and were significantly reduced in Vitamin A-deficient mice. Northern blots showed that circadian expression of the clock genes mPer1, mPer2, Clock, and BMAL1, and of the clock-controlled output gene D-site binding protein (DBP), was maintained in Vitamin A-deficient mice. Our results suggest that dietary Vitamin A is not essential for generating circadian rhythms of peripheral clocks in mammals.