Rapid neuronal differentiation by induced Neurogenin overexpression in human iPS cells AGeneral scheme of Neurogenin 1+2 induction to yield differentiated neurons from human iPS cells after 4 days. Rapid neuronal differentiation by induced Neurogenin overexpression in human iPS cells AGeneral scheme of Neurogenin 1+2 induction to yield differentiated neurons from human iPS cells after 4 days. BProportion of uninduced (white) and 4 days induced (black) iNGN cells analyzed by flow cytometry for the pluripotency marker Tra‐1/60, demonstrating a nearly complete differentiation of iPS cells. CRepresentative transmission light microscopy image of a bipolar‐shaped iNGN cell at day 4 of differentiation. DQuantification of bipolar‐cell‐shaped morphology on day 4, 78 cells analyzed in total. EImmunostaining for MAP2 and nuclear DAPI staining of neurons induced for 4 days (upper row) and uninduced iPS cells (lower row). FQuantification of MAP2‐expressing cells. n refers to the number of cells from three independent experiments as in (E). GImmunostaining for SYN1 of neurons induced for 4 days (upper row) and uninduced iPS cells (lower row). HQuantification of SYN1‐expressing cells. n refers to the number of cells from three independent experiments performed as in (G). I, JCharacterization of action potentials across 10 cells recorded at 4 days (I) or 14 days (J) postinduction. Traces show response to a 20 pA injected current over 0.5 s. Inset shows a representative action potential waveform (in red) with corresponding dV/dt trace (in gray), highlighting threshold and width parameters. Left scale bar: 50 ms/20 mV. Inset scale bar gray: 5 ms/25 mV/ms, red: 25 mV. KPercentage spiking and non‐spiking cells at 4 days and 14 days postinduction. Data information: Scale bars (C, E, G), 20 μm. Two‐sample Student's t‐test, ***P‐value ≤ 0.001. Error bars, ± SEM. Volker Busskamp et al. Mol Syst Biol 2014;10:760 © as stated in the article, figure or figure legend