Conveners
Multiscale modelling of sleep and circadian systems: Part A
- Andrew Phillips (Monash University)
- Svetlana Postnova (University of Sydney)
- Gen Kurosawa ()
Multiscale modelling of sleep and circadian systems: Part B
- Svetlana Postnova (University of Sydney)
- Andrew Phillips (Monash University)
- Gen Kurosawa ()
Description
We spend 1/3 of our life asleep but the mechanisms and purpose of sleep are yet to be fully elucidated. Sleep is essential for healthy physiological function, and its lack leads to increased sleepiness and disease. The daily sleep-wake cycles are controlled by the endogenous circadian (~24 hour) clocks in the brain and the body, which are also responsible for biological rhythms of other functions including metabolism, immunity, and neurodegeneration. The circadian clocks are adjusted by environmental and behavioural time cues; e.g., the light/dark cycle for entrainment of the central circadian clock in the brain. A correct alignment between these time cues, circadian clocks, and behaviour is essential for optimal physiological function. The complex biological systems controlling the circadian clocks and sleep span multiple temporal and spatial scales: from genetic feedback loops and cellular interaction to brain dynamics and physiological functions. This minisymposium will focus on quantitative physiologically based modelling of sleep and circadian clocks at these different scales to reveal the key mechanisms underpinning dynamics of the biological systems involved and to highlight the importance of mathematical and physical research across the different temporal and spatial scales.
Circadian rhythms originate at the cellular level from feedback processes in genetic regulatory networks. Based on experimental observations, computational models of have been proposed for the molecular mechanism of circadian rhythms, which occur spontaneously with a period of the order of 24 h in all eukaryotic organisms, as well as in cyanobacteria. Mathematical models were initially...
Circadian clocks of many organisms consist of cell autonomous rhythms of gene expression in a pacemaker tissue. Negative feedback loops in clock gene regulation are responsible for the generation of the expression rhythms. One of the characteristics of the circadian clock is its phase responses to light input signals. A light signal changes the rates of biochemical reactions in the negative...
Eating behaviour is known to influence our sleep-wake cycle, and the mechanism remains elusive. We have focused on RNA methylation that possibly connect metabolic and circadian systems. Recently, RNA methylation inhibition was found to elongate circadian period by as-yet-unknown mechanism. Since the regulatory network for circadian rhythm has been studied well, modelling can be a powerful tool...
Circadian (~ 24 h) rhythms can be synchronized to the earth’s 24 h periodic environment through external cues such as light - dark (LD) cycle. The misalignment of circadian timings with the external environment can lead to crucial physiological problems, such as jet lag, bipolar disorders and cancer. To treat the misalignment problem, we investigate the pharmacological manipulation of...
Maintaining regular and sufficient sleep is important to many aspects of human health. Mathematical models of human sleep/wake patterns have typically been trained against highly regular, prescribed schedules in healthy individuals under laboratory conditions or idealized versions of real-world work schedules. Consequently, most models are deterministic and do not capture measured...
Background and Objectives: The central circadian clock in the hypothalamus controls 24 hour rhythms in the human body, from sleep and alertness, to mood, metabolism, and immune response among many others. Knowledge of the phase of the clock is central to design of treatments for circadian rhythm disorders, including shiftwork disorder, jetlag, delayed sleep-wake phase disorder, and...
