Fig. 2. Restoring nuclear localization of RS-domain RBM20 variants rescues their splicing function.

a Illustration of the splicing reporter assay. b Ratio of Fluc to Rluc in empty vector control-transfected (pcDNA) or +/– SV40 NLS RBM20 (WT, R634L, S635A, R636S, S637A, S637G, P638L, V914A)-transfected HEK293T cells. Data from one representative experiment is shown, a total of four experiments were analyzed. Each bar shows a mean of four technical replicates with standard errors indicated. c iPSC-CMs with a frameshift (S635FS) mutation transduced with eGFP-WT, eGFP-R634Q, or eGFP-NLS-R634Q, representative images, n = 3. d Numbers of significantly (| log2FC | > 1 and P < 0.1, Wald test with Benjamini–Hochberg correction, DeSeq2⁵⁸) differentially expressed genes in pairwise comparisons of S635FS iPSC-CMs expressing eGFP-WT vs eGFP-R634Q and eGFP-WT vs eGFP-NLS-R634Q. Three biological replicates were analyzed. e PSI values for differential splicing events in the core RBM20 targets between eGFP-WT and eGFP-R634Q cells (|delta PSI| > 0.1, P value < 0.05, two-tailored t-test). Three independent iPSC-CM differentiations were used as biological replicates. Ns = not significant, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, one-way ANOVA with Bonferroni post test, two-sided. Actual P values are shown in the source data file.