IBCS Seminar Series

Abstract:

Intrinsic daily or circadian rhythms in physiology and behaviour are generated by the synchronised activity of neurons within the brain’s master circadian clock in the hypothalamic suprachiasmatic nucleus (SCN). Individual SCN neurons contain the molecular clockwork of which the Cryptochrome (Cry1-2) and Period (Per1-2) genes are important components. This intracellular clock drives changes in excitability, such that SCN neurons are more excited during the circadian day than at night. This enables the SCN to communicate clock phase information or circadian signals to the rest of the brain and body, and gate its responses to environmental cues, such as the light-dark cycle. In my talk, I will present electrophysiological, genetic and intracellular calcium imaging results to show that the disruption of the molecular clockwork activity abolishes day-night rhythms in excitability states of SCN neurons. As a consequence, this disruption influences the ability of SCN cells to gate their daily sensitivity to inputs. I will also provide behavioural data showing that this alteration in the genetic-electrical signalling eliminates SCN-driven circadian rhythms in behaviour. These data provide a tentative mechanism for the enigmatic link between the molecular clock and membrane excitability in SCN neurons.

Brief bio:

Dr. Mino Belle obtained an MBChB degree in Medicine at the University of Cambridge, and subsequently a BSc in Psychology and Neuroscience at the University of Central Lancashire, where he remained to complete a PhD in Neuroendocrinology. He then took up postdoctoral fellowship positions at the University of Liverpool and University of Manchester before obtaining his lectureship at the University of Exeter Medical School.

Mino is a circadian neurophysiologist, and his research focuses on how neurons communicate in health, disease and old age. This includes the understanding of how gene activity in neurons and neuromodulation control the electrical landscape of the brain to influence physiology and behaviour. Over the past ten years, he has been approaching this by studying how circadian rhythms are generated in the brain’s master circadian clock, the suprachiasmatic nucleus, and how these daily signals are communicated and coordinated across the brain and body. He is approaching these questions using experimental and computational methods.