a, Immunofluorescence localization of transfected HA-tagged S1P in MCF10ATk1 cells treated with DMSO or with YM (Y27632+ML7) for 6 hours. Calreticulin stains the endoplasmic reticulum (ER). At least 50 cells per condition. Scale bar 10 μm. b, Immunofluorescent localization of endogenous Insig1 in RPE1 cells treated with DMSO or with YM for 6 hours. Similar results were obtained in MCF10ATk1 cells. At least 50 cells per condition. Scale bar 10 μm. c, Immunofluorescent localization of transfected MYC-tagged SCAP in MCF10ATk1 cells treated with DMSO or with YM for 6 hours. At least 50 cells per condition. Scale bar 10 μm. d, qPCR analysis of SCAP and of established SREBP target genes in MCF10ATk1 48 hours after transfection with two independent siRNAs targeting SCAP (A and B). Data are relative to GAPDH levels; mean expression levels in controls was set to 1, and all other samples are relative to this; n=2 independent biological samples; data are mean and single points. e, Filipin staining of hPSC plated as single-cells or cultured as colonies and treated for 24 hours with 10 μM Y27632. Quantifications and n in Supplementary Table 2. Scale bar 20 μm. The images in panels a, b, c, and e are representative of at least two independent experiments with similar results. n values are pooled across independent experiments. Source data in Supplementary Table 3.