Fed and fasted skeletal muscle of wildtype and PGC-1beta muscle specific knockout mice

The mechanistic underpinnings of the fasting response in skeletal muscle is still poorly understood. We therefore investigated the role of the transcriptional coactivator PGC-1beta (peroxisome proliferator-activated receptor gamma coactivator 1beta) in this context. To do so, the fasting response in quadriceps muscle was assessed in fed and 24 hours fasted mice and compared between wildtype and PGC-1beta muscle-specific knockout mice (both on a C57Bl6/J background). Morphological, functional and transcriptional parameters were determined. The results indicate that PGC-1beta significantly contributes to the metabolic remodelling of skeletal muscle to fasting by promoting catabolic pathways that help to improve energy production and sequester substrates for gluconeogenesis. Accordingly, muscle-specific knockouts for PGC-1beta exhibit mitigated protein degradation and muscle fiber atrophy. These findings contribute to our understanding of muscle plasticity in different metabolic contexts. Quadriceps muscle RNA-seq of wildtype and PGC-1beta muscle specific knockout mice, either fed or fasted for 24 hours, 4 groups, 5 or 4 replicates/mice per group