In mammals, the circadian clock coordinates metabolic pathways, such as glycolysis, gluconeogenesis, fatty acid oxidation and xenobiotic detoxification. These circadian oscillators drive rhythmic expression of clock-controlled genes (ccgs) in various organisms. In eukaryotes, the robustness of circadian oscillations is dependent on cell-autonomous interconnected transcriptional-translational feedback loops. Ĭircadian clocks are molecular oscillators that coordinate metabolism, physiology and behavior of organisms with daily environmental changes. Our observations suggest a substantial plasticity of the circadian transcriptome with respect to the number of rhythmic genes as well as amplitude and phase of the expression rhythms and emphasize a major role of the circadian clock in the temporal organization of metabolism and physiology. The data indicate that the vast majority of transcript rhythms in Neurospora are generated by dawn and dusk specific transcription. Surprisingly, the number of rhythmic transcripts increases about twofold in the absence of CSP1, indicating that rhythmic expression of many genes is attenuated by the activity of CSP1. Genes whose expression is strongly dependent on the core circadian activator WCC fall mainly into the dawn-phased cluster while rhythmic genes regulated by the glucose-dependent repressor CSP1 fall predominantly into the dusk-phased cluster. Dawn-phased genes are predominantly involved in catabolic and dusk-phased genes in anabolic processes, indicating a clock-controlled temporal separation of the physiology of Neurospora. The ccgs accumulate in two main clusters with peak transcription and expression levels either at dawn or dusk. Our data indicate that transcription contributes to the rhythmic expression of the vast majority of clock-controlled genes (ccgs) in Neurospora. Here, we analyzed the clock-controlled transcriptome of Neurospora crassa together with temporal profiles of elongating RNA polymerase II. Moreover, the contribution of post-transcriptional mechanisms in generating rhythms in RNA abundance is not known. The mechanisms generating circadian rhythms, their amplitude and circadian phase are dependent on a transcriptional network of immense complexity. Animals such as possums, raccoons, and squirrels may not seem threatening, however, swerving to avoid hitting something in the road could have disastrous consequences.Circadian clocks control rhythmic expression of a large number of genes in coordination with the 24 hour day-night cycle. Apply this same caution to driving in the city around dawn and dusk. If you have driven in rural areas, you’re probably used to watching roadsides for wildlife. Keep your eyes peeled as you drive through residential areas for anyone on foot or on a bicycle and slow down if you spot someone. Since the sky is still light, pedestrians may believe you can see them. Pedestrians and bikers are difficult to spot during these hours. Be aware that other drivers may be drowsy as well – so watch for vehicles that have trouble maintaining their speed or are swerving between lanes. If you find yourself distracted or having issues focusing on the road, pull over. Because the sun rises late and sets early this time of year, it’s likely you’ll be out driving during these times. Our brain is hard-wired to be sleepy when it’s dark outside. Be sure to do this only when you are parked or your car is not in motion, so that you are not distracted from driving. Make sure you’re still able to read the gauges when dimming the dash. Turning down your dash lights will help prevent the problem. Looking between the bright dash lights and the darkening road can make it difficult for your eyes to adjust in time to spot any issues. Use the switch to ensure your headlights are on and stay on throughout the drive. While many newer cars have daytime running lights and automatic headlight options, don’t take those for granted. In order to stay safe during these hazardous driving times, follow these tips: Turn on your headlights.Īlthough you may not need them to see where you’re driving, your headlights should be switched on to make your vehicle easy to see. The sun is often low enough in the sky to cause glare in drivers’ eyes, while deep shadows can make it difficult to spot changing road conditions. Both dawn and dusk are some of the most dangerous times to drive.
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