Each of the 200+ skeletal muscles in an adult mammal possesses a unique ratio and spatial arrangement of muscle fiber types (fast and slow). This pattern is initiated during embryogenesis, refined postnatally through interactions with "fast" and "slow" motor neurons, and generally maintained throughout adult life. It is even recapitulated after damage to the muscle or the nerve leads to muscle regeneration and/or reinnervation. However, the cellular and molecular mechanisms involved have remained elusive.

Our new data suggest that repulsive interactions between slow myofibers and cells associated with fast motor axons, and potentially between slow myofibers and muscle stem cells (satellite cells) associated with fast myofibers, act to preserve the identity of slow myofibers under conditions that would otherwise promote switching to a faster phenotype.

The seminar will be at 4:00 p.m. in MJIS 1001. Anyone interested in meeting with the speaker should contact Sarah Calve (scalve@purdue.edu)