Fig. 4: LSD1 loop deletion mutant promotes fragmentation and drug resistance.
a Homology model of ΔTTAS LSD1 (salmon) overlaid with wild-type LSD1 (gray) is shown to highlight the deletion of the wild-type loop (cyan) compared to the truncated mutant loop (magenta) (PDB: 2hko). Chemical structure of GSK-LSD1 analog AW4 (32) is shown below. Figure adapted from Vinyard et al.14 b Schematic showing the most abundant genotype in exon 16 after introducing sgT684 and treating with AW4 (32) for 6 weeks to generate the ΔTTAS LSD1 clonal cell line. c Bar plot of relative growth (y-axis) of wild-type and ΔTTAS LSD1 SET-2 cells after 10 day treatment with 1 μM of AW4 (32). d Dose-response curves of recombinant wild-type and ΔTTAS LSD1-CoREST treated with GSK-LSD1 or AW4 (32) relative to vehicle control (n = 3 biological replicates). e Binding curves showing fluorescence polarization (y-axis) for increasing concentrations of LSD1-CoREST (x-axis) in the presence of fluorescently labeled GFI1B(2-10) peptide after treatment with DMSO, GSK-LSD1 (1) or AW4 (32) (n = 2 biological replicates). f MS spectra of FAD adducts formed upon ΔTTAS LSD1-CoREST treatment with AW4 (32) for 24 h following FAD extraction and LC-MS analysis. g Formation of AW4-styrene (34) detected by GC-MS after extracting recombinant ΔTTAS LSD1-CoREST treated with AW4 (32) at the indicated time points. Data in (c) represent mean ± standard error of the mean (s.e.m) across three biological replicates where asterisks denote significant p-values. (****p < 0.0001, ***p < 0.001, **p < 0.01); two-tailed unpaired t-test was performed; wild-type vs ΔTTAS p = 2.23 × 10-6 (t = 40.48, df = 4). Results in (c–g) are representative of two independent experiments. Data in g are provided in Supplementary Data 1. Source data are provided as a Source Data file for (c–g).
