Fig. 2 |. SPTBN1 variants alter protein expression and subcellular distribution.

a, Levels of mutant GFP-βIISp in HEK 293T/17 relative to WT GFP-βIISp. b, Levels of RFP-βIISp proteins in cortical βIISp-KO neurons transduced with indicated RFP-βIISp lentivirus. c, (left) Pluripotency assessment of iPSCs harvesting SPTBN1 variants reprogrammed from PBMCs. Representative bright field images and immunofluorescence staining for pluripotency markers of reprogrammed iPSCs (n = 1 line per variant) collected from one independent experiment. Scale bar, 125 μm. c, (right) TaqMan ScoreCard assessment of pluripotency and trilineage differentiation potential of undifferentiated (top) and differentiated (bottom) p.E1886Q iPSCs. The box plot displays the sample score (color dot) (n = 1) against the internal control reference set (gray box and whiskers) provided by the manufacturer. d, Endogenous βIISp expression in iPSCs of the indicated genotypes. α-tubulin is a loading control. Data in a were compiled from n = 3 biological replicates from three experiments. Data in b (n = 3 biological replicates) and d (n = 1 biological replicate) were collected from three and four independent experiments, respectively. All data represent mean ± SEM. One-way ANOVA with Dunnett’s post hoc test for multiple comparisons. a, *P = 0.0441, ****P < 0.0001. b, *P = 0.0136, **P = 0.0011, ****P < 0.0001. d, *P = 0.0103. e, Immunofluorescence images of HEK 293T/17 cells expressing GFP-βIISp plasmids and stained for actin (phalloidin) and DAPI. Scale bar, 10 μm. White arrowheads indicate GFP-positive aggregates. White asterisk mark cells with increased density of membrane protrusions. Data in e are representative of six independent experiments. See statistics summary in Source Data Figure 2.