Fig. 1
From: Direct reprogramming of urine-derived cells with inducible MyoD for modeling human muscle disease
Transduction of urine-derived cells (UDCs) with an iMyoD lentiviral construct for myogenic reprogramming. a General overview for generating in vitro model of human skeletal muscle using UDCs and iMyoD construct. The cells were first isolated from urine samples and then transduced with lentivirus encoding an inducible MyoD. The construct includes a 4-hydroxytamoxifen (tamoxifen, TAM) response element from the estrogen receptor (ERt) downstream of the basic helix loop helix (bHLH) DNA binding domain of MyoD. After induction with tamoxifen, cells were placed in differentiation media. b Bright-field images of isolated urine cell cultures at passage 3. Scale bar = 25 μm. c Images of immunolabeled MyoD (red) in UDCs after transduction with the iMyoD lentivirus, and iMyoD-transduced urine cells treated with tamoxifen (5 μM, 48 h). Nuclei were marked with Hoechst 33342 (blue). Scale bar = 100 μm. Inset images show increased MyoD localization to the nuclei after tamoxifen. Inset of tamoxifen-treated line 2 cells shows one nuclei with MyoD localization (left) and one without (right). Inset scale bar = 25 μm. d Lentiviral iMyoD transduction efficiency across four control urine cell lines, shown as the percent of MyoD-positive cells relative the total number of cells