Université de Fribourg

Mutation of the circadian clock gene Per2 alters vascular endothelial function

Viswambharan, Hema ; Carvas, João Miguel ; Antic, Vladan ; Marecic, Ana ; Jud, Corinne ; Zaugg, Christian E. ; Ming, Xiu-Fen ; Montani, Jean-Pierre ; Albrecht, Urs ; Yang, Zhihong

In: Circulation, 2007, vol. 115, p. 2188-2195

Background— The circadian clock regulates biological processes including cardiovascular function and metabolism. In the present study, we investigated the role of the circadian clock gene Period2 (Per2) in endothelial function in a mouse model. Methods and Results— Compared with the wild-type littermates, mice with Per2 mutation exhibited impaired...

Université de Fribourg

Impaired daily glucocorticoid rhythm in Per1Brd mice

Dallmann, Robert ; Touma, Chadi ; Palme, Rupert ; Albrecht, Urs ; Steinlechner, Stephan

In: Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology, 2006, vol. 192, no. 7, p. 769-775

Biological clocks have evolved in all kinds of organisms in order to anticipate and adjust to the daily light–dark cycle. Within the last decade, the molecular machinery underlying the circadian system was unraveled. In the present study, the impact of the loss of the Per1 or Per2 genes, key components of the core clock oscillator, on body mass, food and water intake, glucose...

Université de Fribourg

Circadian rhythms in murine pups develop in absence of a functional maternal circadian clock

Jud, Corinne ; Albrecht, Urs

In: Journal of Biological Rhythms, 2006, vol. 21, no. 2, p. 149-154

A genetic approach was used to investigate whether the emergence of circadian rhythms in murine pups is dependent on a functional maternal clock. Arrhythmic females bearing either the mPer1Brdm1/Per2Brdm1 or mPer2Brdm1/Cry1-/- double-mutant genotype were crossed with wild-type males under constant darkness. The heterozygous offspring have the genetic...

Université de Fribourg

Circadian Genes in a Blind Subterranean Mammal III: Molecular Cloning and Circadian Regulation of Cryptochrome Genes in the Blind Subterranean Mole Rat, Spalax Ehrenbergi Superspecies

Avivi, Aaron ; Oster, Henrik ; Joel, Alma ; Beiles, Avigdor ; Albrecht, Urs ; Nevo, Eviatar

In: Journal of Biological Rhythms, 2004, vol. 19, no. 1, p. 22-34

The blind subterranean mole rat superspecies Spalax ehrenbergi is an extreme example of mammalian adaptation to life underground. Though this rodent is totally visually blind, harboring a drastically degenerated subcutaneous rudimentary eye, its daily activity rhythm is entrainable to LD cycles. This indicates that it confers light information to the clock, as has been previously shown by the...