Conférence scientifique | Centre de recherche du CHU Sainte-Justine
Conférencier:
Kenneth Storey, PhD, FRSC, professeur de biochimie, Département de biologie et Département de chimie, Carleton UniversityChaire de recherche du Canada en physiologie moléculaire.
Résumé:
«Edges of Life» have fascinated thinkers from the time of Aristotle. Environmental extremes trigger extreme animal responses. Stresses, from drying to freezing to oxygen deprivation to extreme heat or cold can trigger 'the living dead' – animals that are alive but show no apparent life signs. For example, from our own perspective as homeotherms that are severely injured if core body temperature drops below ~25°C, it is amazing to think about hibernation – mammals descending into a deep torpor and letting their bodies chill to near 0°C. Nature has set in place complex mechanisms to allow animals to “turn down the fires of life” – the basic framework is present in every organism but discovering the biochemical secrets of how to do this is the challenge.
Our lab studies the molecular mechanisms that control metabolic rate suppression. We have identified multiple adaptive strategies that regulate transitions to and from hypometabolism and maintain viability over prolonged dormancy. These include differential gene expression, altered cell signaling pathways, and changes to enzyme properties to alter their function during hypometabolism. This talk will summarize our recent work on the molecular mechanisms of metabolic arrest in mammalian hibernation. Startling similarities exist in basic mechanisms of hypometabolism across phylogeny - indicating, perhaps, that torpor was a basal characteristic of mammals. You, as a human, may have just 'forgotten' this skill.
