Fig. 2From: Expression patterns of FSHD-causing DUX4 and myogenic transcription factors PAX3 and PAX7 are spatially distinct in differentiating human stem cell culturesHuman ES cells and iPS cell clones differentiate into skeletal myocytes with progressive expression of myogenic markers characteristic of early, middle, and late stages of myogenesis. a Schematic of the differentiation protocol. C = CHIRON99021, L = LDN193189, F = FGF2, H = HGF, I = IGF, N2 = neuronal supplement. b–d Images of isogenic clone hiPSC-mosaic1 with the long D4Z4 array. e–g Images of hiPSC-mosaic 1 with the short D4Z4 array. b, e Bright field images of cells at the various stages shown in a. Cell morphology proceeds from small stem-like cells (D7) to spindle-shaped elongated cells more characteristic of myoblasts (D30) to multinucleate elongated fibers on D40. c, f Immunofluorescence images of PAX3-stained cells early in the protocol (D7) that progress to differentiated myocytes with d, g immunoreactivity for PAX7and Titin. Insets show magnified view of cells within the white boxes Back to article page