Circadian systems: different levels of complexity.

Philos Trans R Soc Lond B Biol Sci

Institute for Medical Psychology, Chronobiology, Goethestrasse 31, D-8 0336 München, Germany.

Published: November 2001

After approximately 50 years of circadian research, especially in selected circadian model systems (Drosophila, Neurospora, Gonyaulax and, more recently, cyanobacteria and mammals), we appreciate the enormous complexity of the circadian programme in organisms and cells, as well as in physiological and molecular circuits. Many of our insights into this complexity stem from experimental reductionism that goes as far as testing the interaction of molecular clock components in heterologous systems or in vitro. The results of this enormous endeavour show circadian systems that involve several oscillators, multiple input pathways and feedback loops that contribute to specific circadian qualities but not necessarily to the generation of circadian rhythmicity. For a full appreciation of the circadian programme, the results from different levels of the system eventually have to be put into the context of the organism as a whole and its specific temporal environment. This review summarizes some of the complexities found at the level of organisms, cells and molecules, and highlights similar strategies that apparently solve similar problems at the different levels of the circadian system.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1088544PMC
http://dx.doi.org/10.1098/rstb.2001.0969DOI Listing

Publication Analysis

Top Keywords

circadian
9
circadian systems
8
circadian programme
8
organisms cells
8
systems levels
4
levels complexity
4
complexity years
4
years circadian
4
circadian selected
4
selected circadian
4

Similar Publications

Background: Precision nutrition-based methods develop tailored interventions and/or recommendations accounting for determinants of intra- and inter-individual variation in response to the same diet, compared to current 'one-size-fits-all' population-level approaches. Determinants may include genetics, current dietary habits and eating patterns, circadian rhythms, health status, gut microbiome, socioeconomic and psychosocial characteristics, and physical activity. ​​​​In this systematic review, we examined the evidence base for the effect of interventions based on precision nutrition approaches on overweight and obesity in children and adolescents to help inform future research and global guidelines.

View Article and Find Full Text PDF

Feeding disruptions lead to a significant increase in disease modules in adult mice.

Heliyon

January 2025

CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China.

Feeding disruption is closely linked to numerous diseases, yet the underlying molecular mechanisms remain an important but unresolved issue at the molecular level. We hypothesize that, at the network level, dietary disruptions can alter gene co-expression patterns, leading to an increase in disease-associated modules, and thereby elevating the likelihood of disease occurrence. Here, we investigate this hypothesis using transcriptomic data from a large cohort of adult mice subjected to feeding disruptions.

View Article and Find Full Text PDF

Evaluation of the Digital Ventilated Cage® system for circadian phenotyping.

Sci Rep

January 2025

Sir Jules Thorn Sleep and Circadian Neuroscience Institute, Kavli Institute for Nanoscience Discovery, Nuffield Department of Clinical Neurosciences, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK.

The study of circadian rhythms has been critically dependent upon analysing mouse home cage activity, typically employing wheel running activity under different lighting conditions. Here we assess a novel method, the Digital Ventilated Cage (DVC, Tecniplast SpA, Italy), for circadian phenotyping. Based upon capacitive sensors mounted under black individually ventilated cages with inbuilt LED lighting, each cage becomes an independent light-controlled chamber.

View Article and Find Full Text PDF

Evolutionary pressures adapted insect chemosensation to the respective insect's physiological needs and tasks in their ecological niches. Solitary nocturnal moths rely on their acute olfactory sense to find mates at night. Pheromones are detected with maximized sensitivity and high temporal resolution through mechanisms that are mostly unknown.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!