Figure 1(A) Representative Western Blot analysis of the endogenous p150Glued co-immunoprecipitated with EB1 in shCTL or shSTIM1 ECs (left) and its quantification by normalized densitometry (right). Negative control (CTL) was performed incubating cell lysate with protein A- or G-Sepharose and empty mouse IgG. Results are the average ± SD of three independent assays. shCTL value of each biological replicate was normalized on itself and so shSTIM1 experimental value. Results were analyzed by a parametric two-tailed analysis of variance (ANOVA) with Bonferroni post hoc analysis. ANOVA p≤ 0,001; Bonferroni for shCTL and shSTIM1 p≤ 0,05 *. (B) Representative of three Western Blot analysis of endogenous p150Glued, light-intermediate chain (LIC) of cytoplasmic dynein 1 and EB1 immunoprecipitated with STIM1 in wild-type ECs. Negative control (CTL) was performed incubating cell lysate with protein A- or G-Sepharose and empty rabbit IgG. (D) Representative Western Blot analysis of increasing amount of GST-STIM1 (cytoplasmic domain) pulled down by Cap-Gly-CC1-p150Glued-V5-coated beads, in absence or presence of FLAG-EB1 C-terminal. Colors label the protein as in (c). Negative control was performed using equal amount of empty GST protein, together with Cap-Gly-CC1-p150Glued.(E) Representative Western Blot analysis of mCherry-p150Glued WT co-immunoprecipitated with GFP-STIM1 WT, NN, ΔCC1-3/WT (ΔCC/WT) or ΔCC1-3/NN (ΔCC/NN) in co-transfected HEK 293T cells. Negative control (CTL) was performed incubating cell lysate from HEK 293T co-transfected with an empty GFP vector together with mCherry-P150Glued WT with pre-cleared protein A or G-Sepharose and the rabbit GFP antibody. Below, its quantification by normalized densitometry. Results are the average ± SD of three independent assays. The value of P150Glued co-immunoprecipitated with GFP-STIM1 WT from each biological replicate was normalized on itself and so those immunoprecipitated with GFP-STIM1 NN, ΔCC/WT or ΔCC/NN. Results were analyzed by a parametric two-tailed analysis of variance (ANOVA) with Bonferroni post hoc analysis. ANOVA p≤ 0,001; Bonferroni for STIM1 WT and NN p> 0.05 not significant (ns), for STIM1 WT and ΔCC/WT p> 0.05 not significant (ns) and for STIM1 WT and ΔCC/NN p≤ 0,05 *. (F) Representative Western Blot analysis of GST-STIM1 (cytoplasmic domain) pulled down by Cap-Gly-CC1-p150Glued-V5-coated beads, in presence of FLAG-EB1 C-terminal WT or ΔY. Negative control was performed using equal amount of empty GST protein, together with Cap-Gly-CC1-p150Glued.  (G) Confocal microscopy analysis of wild-type ECs, transiently transfected with GFP-STIM1 WT or, NN or ΔCC1-3/WT (ΔCC/WT) together with mCherry-P150Glued. Scale bar = 10 μm. Right insets are shown to highlight MT-bound p150Glued+ punctae (arrows), colocalized with STIM1. Scale bar = 5 μm. (H) Average number of the mCherry-P150Glued+ punctae in the same cells as in (g). Counts are the average ± SEM of three independent experiments for a total of 150 punctae (30 cells). Results were analyzed by a parametric two-tailed analysis of variance (ANOVA) with Bonferroni post hoc analysis. ANOVA p≤ 0,001; Bonferroni for STIM1 WT and NN p≤ 0,001 *** and for STIM1 WT and ΔCC/WT p> 0.05 not significant (ns). (I) Co-localization analysis of mCherry-P150Glued with GFP-STIM1 WT, NN or ΔCC1-3/WT (ΔCC/WT), transiently co-transfected in ECs, as in (g). Results are the average ± SEM of three independent experiments for a total of 150 punctae (30 cells) and analyzed by a parametric two-tailed analysis of variance (ANOVA) with Bonferroni post hoc analysis. ANOVA p≤ 0,001; Bonferroni for STIM1 WT and NN p≤ 0,001 *** and for STIM1 WT and ΔCC/WT p> 0.05 not significant (ns).