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

cGMP-dependent protein kinase I, the circadian clock, sleep, and learning

Feil, Robert ; Hölter, Sabine M. ; Weindl, Karin ; Wurst, Wolfgang ; Langmesser, Sonja ; Gerling, Andrea ; Feil, Susanne ; Albrecht, Urs

In: Communicative & Integrative Biology, 2009, vol. 2, no. 4, p. 298 - 301

The second messenger cGMP controls cardiovascular and gastrointestinal homeostasis in mammals. However, its physiological relevance in the nervous system is poorly understood. Now, we have reported that the cGMP-dependent protein kinase type I (PRKG1) is implicated in the regulation of the timing and quality of sleep and wakefulness. Prkg1 mutant mice showed altered distribution of sleep and...

Université de Fribourg

cGMP-dependent protein kinase type I is implicated in the regulation of the timing and quality of sleep and wakefulness

Langmesser, Sonja ; Franken, Paul ; Feil, Susanne ; Emmenegger, Yann ; Albrecht, Urs ; Feil, Robert

In: PLoS ONE, 2009, vol. 4, no. 1, p. e4238

Many effects of nitric oxide (NO) are mediated by the activation of guanylyl cyclases and subsequent production of the second messenger cyclic guanosine-3′,5′-monophosphate (cGMP). cGMP activates cGMP-dependent protein kinases (PRKGs), which can therefore be considered downstream effectors of NO signaling. Since NO is thought to be involved in the regulation of both sleep and circadian...

Université de Fribourg

Interaction of circadian clock proteins PER2 and CRY with BMAL1 and CLOCK

Langmesser, Sonja ; Tallone, Tiziano ; Bordon, Alain ; Rusconi, Sandro ; Albrecht, Urs

In: BMC Molecular Biology, 2008, vol. 9, p. 41

Background: Circadian oscillation of clock-controlled gene expression is mainly regulated at the transcriptional level. Heterodimers of CLOCK and BMAL1 act as activators of target gene transcription; however, interactions of PER and CRY proteins with the heterodimer abolish its transcriptional activation capacity. PER and CRY are therefore referred to as negative regulators of the circadian...

Université de Fribourg

Differential gene expression between human schwannoma and control Schwann cells

Hanemann, C. O. ; Bartelt-Kirbach, B. ; Diebold, R. ; Kämpchen, K. ; Langmesser, Sonja ; Utermark, T.

In: Neuropathology and Applied Neurobiology, 2006, vol. 32, no. 6, p. 605–614

The NF2 gene encodes the tumour suppressor protein merlin. The mutation of a single allele of this gene causes the autosomal dominantly inherited disease neurofibromatosis type 2 (NF2), which is characterized mainly by vestibular schwannoma carrying a second hit mutation. Complete lack of merlin is also found in spontaneous schwannomas and meningiomas. As the events leading to schwannoma...

Université de Fribourg

Life time—circadian clocks, mitochondria and metabolism

Langmesser, Sonja ; Albrecht, Urs

In: Chronobiology International, 2006, vol. 23, no. 1-2, p. 51–157

A functional circadian clock has long been considered a selective advantage. Accumulating evidence shows that the clock coordinates a variety of physiological processes in order to schedule them to the optimal time of day and thus to synchronize metabolism to changes in external conditions. In mitochondria, both metabolic and cellular defense mechanisms are carefully regulated. Abnormal clock...