The rhythms of emergence, oxygen consumption, and activity
were studied in Megachile rotundata with the object of comparing the
results to the major properties of the biological clock such as temperature
independence, susceptibility to light synchronization, and
entrainment. A further objective was to compare the three rhythms
to determine if...
Circadian clocks are internal mechanisms regulating many physiological processes.
Research suggests that the circadian clock may regulate repair of cellular damage caused
by reactive oxygen species (ROS), but molecular pathways from the clock to ROS repair
are not known. The gene cncC, known in mammals as Nrf2, and its repressor...
Circadian clocks coordinate molecular, cellular, physiological, and behavioral processes with the 24-hour solar day. While clock functions are well understood in young animals, it is not clear how aging or neurodegenerative disease affects the various levels of the circadian system. A common symptom of many neurodegenerative diseases including Alzheimer’s disease...
Daily (circadian) rhythms exist at molecular, physiological, and behavioral levels and coordinate many life functions. This coordination is believed to contribute to an organism's fitness, however, such contributions have not been convincingly demonstrated in any animal. The most significant measure of fitness is the reproductive output of the individual and...
Circadian rhythms are the daily oscillations in multiple organism functions, from clock gene expression to behavior. Lost or irregular rhythms lead to health problems later in life including nervous system disorders, abnormal sleep/activity cycles, diabetes and obesity. However, it is not known whether strengthening the expression of clock genes throughout...
Circadian clocks generate daily rhythms in neuronal, physiological, and metabolic functions. Previous studies in mammals reported daily fluctuations in levels of the major endogenous antioxidant, glutathione (GSH), but the molecular mechanisms that govern such fluctuations remained unknown. To address this question, we used the model species Drosophila, which has a...
Circadian clocks generate rhythms in molecular, cellular, physiological, and behavioral processes. Recent studies suggest that disruption of the clock mechanism accelerates organismal senescence and age-related pathologies in mammals. Impaired circadian rhythms are observed in many neurological diseases; however, it is not clear whether loss of rhythms is the cause or...
Circadian clocks maintain temporal homeostasis by generating daily output rhythms in molecular, cellular, and physiological functions. Output rhythms, such as sleep/wake cycles and hormonal fluctuations, tend to deteriorate during aging in humans, rodents, and fruit flies. However, it is not clear whether this decay is caused by defects in the...
All organisms possess circadian clocks, which generate daily oscillations in clock controlled gene expression that regulate many essential biological functions in synchrony with the 24-hour light/dark cycles. When the genes that control the internal clock are weakened, accelerated aging symptoms are observed. Past research in Drosophila demonstrated that aging flies...
Endogenous circadian clock regulation is essential to normal rhythmicity, particularly the timing of hormone release in the brain. In the context of mammalian reproduction, a surge of a specific hormone, gonadotrophin-releasing hormone (GnRH), initiates a surge of luteinizing hormone (LH) from the pituitary gland, which is required for ovulation in...