FIGURE 4.

Protein arginine methyltransferase inhibition improves induced pluripotent stem cell (iPSC)-motor neuron (MN) survival in response to polyGR₁₅ challenge. (A) Representative image of tdTomato⁺ CRE-VACHT-tdTomato control motor neurons employed in polyGR₁₅–PRMT inhibitor cross-titration. (B) Timeline for cross-titration experiment. Neurons were differentiated to spinal motor neurons, and on day 1, dissociated and plated into 384-well plates. After 12 days, neurons were treated with polyGR₁₅ concentrations ranging from 100 nM to 10 μM, and co-treated with MS023 or MS094 concentrations ranging from 32 nM to 10 μM. Cell survival was measured 24 or 48 h after treatment. (C) Neuronal survival following polyGR₁₅ co-treated with MS023 normalized to vehicle treated wells (0.2% DMSO). (D) Neuronal survival following polyGR₁₅ co-treated with MS023 normalized to vehicle treated wells (0.2% DMSO). *Denotes p < 0.05, and **denotes p < 0.01 (comparing MS023 or MS094 co-treated groups to polyGR₁₅ alone by one-way ANOVA analysis of variance followed by Dunnett’s test). Data are presented as mean values ± standard deviations (error bars).