Cell-autonomous and Circuit-level Mechanisms of Circadian Timekeeping in Mammals: Genes, Neurons and Astrocytes
In mammals the cell-autonomous circadian clock pivots around a transcriptional/post-translational feedback loop. However, we remain largely ignorant of the critical molecular, cell biological, and circuit-level processes that determine the precision and robustness of circadian rhythms: what keeps them on track, and what determines their period, which varies by less than 5 minutes over 24 hours? The origin of this precision and robustness is the suprachiasmatic nucleus (SCN) of the basal hypothalamus, the principal circadian pacemaker of the brain. The SCN sits atop a circadian hierarchy that sustains and synchronises the innumerable cell-autonomous clocks of all major organs to solar time (and thereby to each other), by virtue of direct retinal innervation that entrains the transcriptional oscillator of the 20,000 or so component cells of the SCN. I shall describe real-time imaging approaches to monitor circadian cycles of gene expression and cellular function in the SCN, and intersectional genetic and pharmacological explorations of the cell-autonomous and circuit-level mechanisms of circadian timekeeping. A particular focus will be on “translational switching” approaches to controlling clock function and the surprising discovery of a central role for SCN astrocytes in controlling circadian behaviour.
Date: 20 February 2019, 12:00 (Wednesday, 6th week, Hilary 2019)
Venue: Oxford Martin School, 34 Broad Street OX1 3BD
Venue Details: Oxford Martin School, 34 Broad Street
Speaker: Michael Hastings (MRC Laboratory of Molecular Biology, Cambridge )
Organising department: Department of Physiology, Anatomy and Genetics (DPAG)
Organiser: Fiona Woods (University of Oxford, Department of Physiology Anatomy and Genetics, Centre for Neural Circuits and Behaviour)
Organiser contact email address: fiona.woods@cncb.ox.ac.uk
Part of: CNCB Seminar Series
Booking required?: Not required
Audience: Members of the University only
Editor: Fiona Woods