Professor Dr. Thomas Braun
Director, Max Planck Institute for Heart and Lung Research
Germany

Date: Thursday, 1-February-2018
Time: 4:30 PM
Venue: Rm. A2-08, 2/F, Mrs. Chen Yang Foo Oi Telemedicine Centre
William MW Mong Block, Faculty of Medicine Building
21 Sassoon Road, Pokfulam, Hong Kong

Summary:
Muscle stem cells undergo a dramatic metabolic switch to oxidative phosphorylation during differentiation, which is achieved by massively increased mitochondrial activity. Since expression of several muscle-specific miRNA genes correlates with increased mitochondrial activity during muscle stem cell differentiation, we examined their potential role in metabolic maturation of skeletal muscles in mice. We discovered a new regulatory loop that regulates the Dlk1-Dio3 gene cluster, which encodes multiple miRNAs inhibiting expression of mitochondrial genes to establish a stem cell-like metabolic program. Failure to terminate the program profoundly changes muscle physiology, essentially abrogating endurance running. Furthermore, we investigated the molecular circuits controlling survival of muscle stem cells in damaged muscles, which are not well understood. We identified an epigenetic control mechanism that directs expression of molecules involved in programmed cell death in muscle stem cells. Disruption of this process, which protects muscle stem cells in acute disease conditions, during chronic inflammation, e.g. in muscle dystrophies, increased necroptosis, prevented expansion of muscle stem cells after injury and abrogated efficient muscle regeneration.

ALL ARE WELCOME