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Updated: Jun 19, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Circadian clocks - the fall and rise of physiology
Till Roenneberg1, Martha Merrow
1Centre for Chronobiology, Institute of Medical Psychology, Medical Faculty, University of Munich, Goethestrasse 31, D-80336 Munich, Germany. roenneberg@lmu.de
Abstract:
Circadian clocks control the daily life of most light-sensitive organisms - from cyanobacteria to humans. Molecular processes generate cellular rhythmicity, and cellular clocks in animals coordinate rhythms through interaction (known as coupling). This hierarchy of clocks generates a complex, approximately 24-hour temporal programme that is synchronized with the rotation of the Earth. The circadian system ensures anticipation and adaptation to daily environmental changes, and functions on different levels - from gene expression to behaviour. Circadian research is a remarkable example of interdisciplinarity, unravelling the complex mechanisms that underlie a ubiquitous biological programme. Insights from this research will help to optimize medical diagnostics and therapy, as well as adjust social and biological timing on the individual level.
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