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

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

WC-1 and the proximal GATA sequence mediate a cis-/trans-acting repressive regulation of light-dependent gene transcription in the dark

Brenna, Andrea ; Talora, Claudio

In: International Journal of Molecular Sciences, 2019, vol. 20, no. 12, p. 2854

Light influences a wide range of physiological processes from prokaryotes to mammals. Neurospora crassa represents an important model system used for studying this signal pathway. At molecular levels, the WHITE COLLAR Complex (WCC), a heterodimer formed by WC-1 (the blue light photo-sensor) and WC-2 (the transcriptional activator), is the critical positive regulator of light-dependent gene ...

Université de Fribourg

REV-ERBα influences the stability and nuclear localization of the glucocorticoid receptor

Okabe, Takashi ; Chavan, Rohit ; Costa, Sara S. Fonseca ; Brenna, Andrea ; Ripperger, Jürgen A. ; Albrecht, Urs

In: Journal of Cell Science, 2016, vol. 129, no. 21, p. 4143–4154

REV-ERBα (encoded by Nr1d1) is a nuclear receptor that is part of the circadian clock mechanism and regulates metabolism and inflammatory processes. The glucocorticoid receptor (GR, encoded by Nr3c1) influences similar processes, but is not part of the circadian clock, although glucocorticoid signaling affects resetting of the circadian clock in peripheral tissues. Because of their similar...

Université de Fribourg

Epigenetic and posttranslational modifications in light signal transduction and the circadian clock in Neurospora crassa

Proietto, Marco ; Bianchi, Michele Maria ; Ballario, Paola ; Brenna, Andrea

In: International Journal of Molecular Sciences, 2015, vol. 16, no. 7, p. 15347–15383

Blue light, a key abiotic signal, regulates a wide variety of physiological processes in many organisms. One of these phenomena is the circadian rhythm presents in organisms sensitive to the phase-setting effects of blue light and under control of the daily alternation of light and dark. Circadian clocks consist of autoregulatory alternating negative and positive feedback loops intimately...