Université de Fribourg

Phosphorylation and circadian molecular timing

Brenna, Andrea ; Albrecht, Urs

In: Frontiers in Physiology, 2020, vol. 11, p. -

Endogenous circadian rhythms are biological processes generated by an internal body clock. They are self-sustaining, and they govern biochemical and physiological processes. However, circadian rhythms are influenced by many external stimuli to reprogram the phase in response to environmental change. Through their adaptability to environmental changes, they synchronize physiological responses...

Université de Fribourg

Changing the light schedule in late pregnancy alters birth timing in mice

Amano, Tomoko ; Ripperger, Jürgen A. ; Albrecht, Urs

In: Theriogenology, 2020, vol. 154, p. 212–222

In rats, birth timing is affected by changes in the light schedule until the middle of the pregnancy period. This phenomenon can be used to control birth timing in the animal industry and/or clinical fields. However, changes in the light schedule until the middle of the pregnancy period can damage the fetus by affecting the development of the major organs. Thus, we compared birth timing in...

Université de Fribourg

Molecular connections between circadian clocks and mood-related behaviors

Albrecht, Urs

In: Journal of Molecular Biology, 2020, vol. 432, no. 12, p. 3714–3721

The circadian system consists of individual cellular clocks. It organizes and synchronizes biochemical and physiological processes in order to optimally adapt an organism to its environment. This requires that the circadian system is responsive to environmental cues, which contain information about geophysical time (e.g., light), and allows an organism to predict daily recurring events....

Université de Fribourg

Cyclin-dependent kinase 5 (CDK5) regulates the circadian clock

Brenna, Andrea ; Olejniczak, Iwona ; Chavan, Rohit ; Ripperger, Jürgen A. ; Langmesser, Sonja ; Cameroni, Elisabetta ; Hu, Zehan ; De Virgilio, Claudio ; Dengjel, Jörn ; Albrecht, Urs

In: eLife, 2019, vol. 8, p. e50925

Circadian oscillations emerge from transcriptional and post-translational feedback loops. An important step in generating rhythmicity is the translocation of clock components into the nucleus, which is regulated in many cases by kinases. In mammals, the kinase promoting the nuclear import of the key clock component Period 2 (PER2) is unknown. Here, we show that the cyclin-dependent kinase 5...

Université de Fribourg

Medicine in the fourth dimension

R.Cederroth, Christopher ; Albrecht, Urs ; Bass, Joseph ; Brown, Steven A. ; Dyhrfjeld-Johnsen, Jonas ; Gachon, Frederic ; Green, Carla B. ; Hastings, Michael H. ; Helfrich-Förster, Charlotte ; B.Hogenesch, John ; Lévi, Francis ; Loudon, Andrew ; B.Lundkvist, Gabriella ; H.Meijer, Johanna ; Rosbash, Michael ; S.Takahashi, Joseph ; Young, Michael ; Canlon, Barbara

In: Cell Metabolism, 2019, vol. 30, no. 2, p. 238–250

The importance of circadian biology has rarely been considered in pre-clinical studies, and even more when translating to the bedside. Circadian biology is becoming a critical factor for improving drug efficacy and diminishing drug toxicity. Indeed, there is emerging evidence showing that some drugs are more effective at nighttime than daytime, whereas for others it is the opposite. This...

Université de Fribourg

Circadian clocks and sleep: impact of rhythmic metabolism and waste clearance on the brain

Albrecht, Urs ; Ripperger, Jürgen A.

In: Trends in Neurosciences, 2018, vol. 41, no. 10, p. 677–688

The rotation of the Earth around its axis causes periodic exposure of half of its surface to sunlight. This daily recurring event has been internalized in most organisms in the form of cellular circadian clock mechanisms. These cellular clocks are synchronized with each other in various ways to establish circadian networks that build the circadian program in tissues and organs, coordinating...

Consortium of Swiss Academic Libraries

Circadian rhythms and sleep—the metabolic connection

Albrecht, Urs

In: Pflügers Archiv - European Journal of Physiology, 2012, vol. 463, no. 1, p. 23-30

Université de Fribourg

Circadian control of DRP1 activity regulates mitochondrial dynamics and bioenergetics

Schmitt, Karen ; Grimm, Amandine ; Dallmann, Robert ; Oettinghaus, Bjoern ; Restelli, Lisa Michelle ; Witzig, Melissa ; Ishihara, Naotada ; Mihara, Katsuyoshi ; Ripperger, Jürgen A. ; Albrecht, Urs ; Frank, Stephan ; Brown, Steven A. ; Eckert, Anne

In: Cell Metabolism, 2018, vol. 27, no. 3, p. 657-666.e5

Mitochondrial fission-fusion dynamics and mitochondrial bioenergetics, including oxidative phosphorylation and generation of ATP, are strongly clock controlled. Here we show that these circadian oscillations depend on circadian modification of dynamin-related protein 1 (DRP1), a key mediator of mitochondrial fission. We used a combination of in vitro and in vivo models, including human skin...

Université de Fribourg

VGLUT1 binding to endophilin or intersectin1 and dynamin phosphorylation in a diurnal context

Richter, Karin ; Schmutz, Isabelle ; Darna, Mahesh ; Zander, Johannes-F ; Chavan, Rohit ; Albrecht, Urs ; Ahnert-Hilger, Gudrun

In: Neuroscience, 2018, vol. 371, p. 29–37

Glutamate is concentrated into synaptic vesicles (SV) by the vesicular glutamate transporters (VGLUT) 1 and 2. VGLUTs also harbor a Na+/Pi-transport activity when residing at the plasma membrane. Here we aimed to identify whether the diurnal switches of VGLUT1 parallels interactions with or modification of endocytic proteins.VGLUT1 and dynamin bind to SH3 domains of either endophilin (Enph)...