Persistent PKA activation promoted the correlative distribution of Na V 1.5, β-Tub, and EB1 on myocytes’ surface and ICDs. Top: Cartoon depicting the planes of view. (A) Left: 2-D views of NaV1.5, β-Tub, and EB1 immunofluorescence on myocytes’ surface. Right: 3-D views of NaV1.5, β-Tub, and EB1 immunofluorescence at myocytes’ ICD. For each myocyte, six panels are shown: NaV1.5, β-Tub, and EB1 individual immunofluorescence (upper row), and merged (lower row). In the PKA myocyte’s surface images (lower left), cyan dotted circles denote looped microtubules (β-Tub panel) overlapped with EB1 puncta (EB1 panel). In the ICD images (right), semitransparent blue surfaces denote nCadherin-demarcated ICD volumes. (B) Box plots of thresholded Pearson correlation coefficients between the pairs of immunofluorescence signals listed along the abscissa in CON and PKA myocytes. Data were pooled from 29 to 41 myocytes per group from two independent experiments. Listed P values are from t tests between CON and PKA myocytes. In A, scale bars are 5 μm for the myocyte surface views (left) and 2 μm for the myocyte ICD 3-D views (right).
