01
Research
Biological rhythms with a period of about 24 hours are called circadian rhythms (from Latin circa dies, meaning "about a day"). Circadian rhythms exist at all levels of complexity, from gene expression to rhythms in physiology, metabolism, and behavior. They are generated by an internal timing system - an endogenous circadian clock - that allows organisms to anticipate daily changes in their environment. Light acts as the primary stimulus to synchronize the internal clock with the external world. In mammals, circadian clocks have been found in almost every cell, but they are organized hierarchically: A tiny brain structure, the suprachiasmatic nucleus (SCN) of the hypothalamus, is known to be the main pacemaker. Specialized neurons in the retina sense light and relay this information to the SCN via the retinohypothalamic tract. Peripheral clocks in other tissues are synchronized by the SCN and are responsible for regulating organ-specific rhythms in physiology and metabolism.
Over the past three decades, the molecular mechanism of circadian rhythm generation has been uncovered and the associated genes and gene variants have been identified. It is now clear that synchronization between endogenous circadian and exogenous environmental cycles is critical for health and well-being. However, modern life constantly challenges our internal clock, which can lead to circadian rhythm disruption. Today, it is undeniable that circadian rhythm disruption is associated with many common diseases, including sleep disorders, psychiatric and neurodegenerative diseases, metabolic and cardiovascular disorders, immune system dysfunctions, as well as cancer. The description of the underlying mechanisms, however, has only just begun.
02
Interests
Our group aims to advance the emerging field of Circadian Medicine by translating fundamental insights from chronobiology into clinical applications. We are excited to announce the launch of the new DFG-funded transregional Collaborative Research Center (CRC) “Foundations of Circadian Medicine” (www.circadianmedicine.de), coordinated by Charité – Universitätsmedizin Berlin. Starting in October 2025, this interdisciplinary consortium brings together researchers from basic and clinical sciences to investigate how circadian rhythms influence health and disease across organs and clinical contexts. In addition to coordinating the CRC, our lab contributes to both its molecular and translational arms—ranging from mechanistic studies of circadian regulation to the development of diagnostic tools and chronomedical interventions. This CRC represents a major step toward establishing Circadian Medicine as a new field at the intersection of chronobiology and biomedicine.
To support these translational efforts, we are developing novel biomarker assays that allow easy and reliable readout of key characteristics of the human internal clock from a single biospecimen (e.g., blood or hair root cells). This “detecting the clock” approach has practical relevance on several levels: (i) Disease therapy might benefit significantly from an approach adapted to internal time (precision medicine). (ii) Disruption of the circadian clock by artificial light, shift work, travel across time zones, social jet lag, and daylight saving time changes has been associated with a variety of common diseases. Therefore, aligning internal and external time—as well as harmonizing organ clocks within the body—is essential for disease prevention. (iii) In addition to the therapeutic and preventive aspects, circadian diagnostics can help reduce circadian rhythm disturbances in shift workers, e.g., by implementing chronotype-based shift schedules, and support treatment strategies for patients with circadian rhythm disorders.
To support these translational efforts, we are developing novel biomarker assays that allow easy and reliable readout of key characteristics of the human internal clock from a single biospecimen (e.g., blood or hair root cells). This “detecting the clock” approach has practical relevance on several levels: (i) Disease therapy might benefit significantly from an approach adapted to internal time (precision medicine). (ii) Disruption of the circadian clock by artificial light, shift work, travel across time zones, social jet lag, and daylight saving time changes has been associated with a variety of common diseases. Therefore, aligning internal and external time—as well as harmonizing organ clocks within the body—is essential for disease prevention. (iii) In addition to the therapeutic and preventive aspects, circadian diagnostics can help reduce circadian rhythm disturbances in shift workers, e.g., by implementing chronotype-based shift schedules, and support treatment strategies for patients with circadian rhythm disorders.
At the same time, we continue to investigate the fundamental principles of circadian biology, which form the scientific foundation for our translational work. We study the regulation of intra- and intercellular mechanisms that generate high-amplitude circadian oscillations using biochemical, genetic, molecular, and cell-biological approaches (funding by Deutsche Forschungsgemeinschaft TRR168). For example, we have developed novel reporter cell lines that enable single-cell fluorescence microscopy of clock protein dynamics. In collaboration with theoretical biologists and mathematicians, we also develop quantitative models to understand how molecular oscillations arise and how synchrony is achieved within and between cells.