Fig. 5.

KCNH1 mutations induce basal SHH pathway activation. (a) Histograms show the expression levels of target genes of the SHH pathway (GLI1, PTCH1, and SMO) in fibroblasts from patients carrying KCNH1^R330Q and KCNH1^L352V mutations compared to control cells. Fibroblasts were serum-starved for 48 h and treated with SAG 100 nM. GAPDH was used as a reference gene for normalization. Data are represented as mean + sem. Differences between groups were analyzed by one-tailed Student’s t test. *p < 0.05 is reported vs the same condition of wild-type unless otherwise indicated with bars. (b) Representative images of IF analysis of ciliary localization of SMO (red) and ARL13B (green) in SAG treated wild-type and patients’ fibroblasts carrying KCNH1^R330Q and KCNH1^L352V mutations. Scale bars 10 µm. (c) Percentage of cells with cilia of different morphology (normal, fragmented, and bulbous). (d) Graph of cilia length measurements of KCNH1^WT, KCNH1^R330Q, and KCNH1^L352V fibroblasts in control and SHH pathway activation condition. Data are represented as mean + sem. Differences between two groups were analyzed by unpaired Student’s t test. *p < 0.05 is reported vs the same condition of wild-type unless otherwise indicated with bars