Isolation and culture of muscle stem cells

Polycomb group (PcG) proteins are key epigenetic factors responsible for the proper spatiotemporal repression of defi ned transcriptional programs along the process of cell differentiation, including myogenesis. The discovery of the pivotal role played by PcG factors during myogenic differentiation relied on the possibility to culture myogenic cells in vitro. We describe here the methods currently used to isolate muscle stem cells (MuSCs) both from single myofi bers and from bulk muscles by fl uorescence-activated cell sorting (FACS), highlighting experimental details and critical steps. Through these techniques MuSCs can be effi ciently isolated and cultured in vitro to recapitulate the different phases of myogenesis: activation, expansion, differentiation, and self-renewal.