Institute of Medical Psychology

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Merrow Lab - Molecular Chronobiology


Research Topics

  • Clock in the eurkaryotic cell
  • Clocks in prokaryotes
  • Sleep and Memory

Prof. Martha Merrow, PhD. 

phone: +49 (0)89 - 2180 75650




We are all ruled by our circadian clocks! They specify when we sleep and wake, how well we perform, how we feel. The Molecular Chronobiology lab at the IMP tries to explain circadian behavior from the lowest levels of complexity – molecules and cells – to understand circadian clock properties and behaviour. Only through the description of the clock at this level can we understand how ’circadian organisation’ leads to higher-level properties. One key question that must be addressed for all circadian systems is how entrainment or synchronization occurs. Another question is how circadian clocks work in under-investigated model systems. Non-photosynthetic bacteria make up over 10% of the biomass on Earth yet we know almost nothing about their circadian clocks.

What are our tools? We favour simple model systems, such as human tissue culture cells, Saccahromyces cerevisiae and Bacillus subtilis. We use entrained phase of the clock (when oscillations occur within a zeitgeber cycle) to understand how the clock functions. We follow molecular oscillations from RNA to protein to post-translational modifications, when possible, using high-throughput methods (luciferase and GFP reporters, proteomics and transcriptomics).
We observe that clocks in the simplest systems share properties with those described over the last decades for organisms. This makes the concept of ‘circadian organisation’ – how the system comes together to function as an orderly unit - a central challenge for chronobiology research. 

Selected Publications

Principles underlying the complex dynamics of temperature entrainment by a circadian clock.
Burt P, Grabe S, Madeti C, Upadhyay A, Merrow M, Roenneberg T, Herzel H, Schmal C.iScience. 2021 Oct 30;24(11):103370. doi: 10.1016/j.isci.2021.103370. eCollection 2021 Nov 19. PubMed

The Circadian Clock, the Brain, and COVID-19: The Cases of Olfaction and the Timing of Sleep.
Herz RS, Herzog ED, Merrow M, Noya SB.J Biol Rhythms. 2021 Oct;36(5):423-431. doi: 10.1177/07487304211031206. Epub 2021 Aug 15. PubMed

A circadian clock in a nonphotosynthetic prokaryote.
Eelderink-Chen Z, Bosman J, Sartor F, Dodd AN, Kovács ÁT, Merrow M.Sci Adv. 2021 Jan 8;7(2):eabe2086. doi: 10.1126/sciadv.abe2086. Print 2021 Jan. PubMed

A functional context for heterogeneity of the circadian clock in cells.
Merrow M, Harrington M.PLoS Biol. 2020 Oct 14;18(10):e3000927. doi: 10.1371/journal.pbio.3000927. eCollection 2020 Oct. Pubmed

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