Fig. 6

Fig. 6

SSH1 Regulates Cardiomyocyte Myofilament Maturation

(A) 3D images of a 103 hpf EGFP-Ssh1a expressing ventricle immediately after cardiac arrest and 2 h after tricaine treatment; fluorescence intensities along white dashed lines. EGFP-Ssh1a colocalizes with Vcl-tdTomato in CMs (arrowheads), but this co-localization is abrogated by tricaine treatment.

(B) 3D images of a 103 hpf vclb^−/− ventricle expressing EGFP-Ssh1a; fluorescence intensities along white dashed line (n = 3 animals; each animal contains 2–4 EGFP-Ssh1a⁺ CMs).

(C) VCL and HA immunostaining of HeLa cells treated without or with blebbistatin; fluorescence intensities along white dashed lines. HA-SSH1 colocalizes with VCL (arrowheads), and blebbistatin treatment leads to loss of this co-localization.

(D) Protein expression after siRNA transfection in mouse neonatal CMs exposed to cyclic stretch; relative levels of p-CFL (n = 4).

(E) Protein expression in RNCMs exposed to cyclic stretch; relative levels of p-CFL (n = 3).

(F) 3D images of 103 hpf hearts treated without or with Ssh inhibitor from 72 to 103 hpf. Myofilament thickness measured in 103 hpf ventricles (n = 5 ventricles).

(G) 3D images of 100 hpf ventricle. DN Ssh1a overexpression leads to myofilament disruption (arrowheads). Myofilament thickness measured in 100 hpf CMs (n = 7–10 CMs). Error bars, SEM. ^∗p < 0.05 by ANOVA followed by Tukey’s HSD test. Scale bars, 20 μm in (A), (B), (F), and (G); 10 μm in (C).