Figure 1. Myoscape expression profile and subcellular localization.

(a) Mouse muscle and heart Myoscape mRNA expression profile confirmed by HPRT1-normalized quantitative qPCR and (b) additional Northern blot analyses of multiple human tissues using Myoscape-specific probes and primers. Confirmation of the interaction between α-actinin 2 (c) and the skeletal muscle-specific pore-forming unit (d) of the LTCC (CACNA 1S) with myc-tagged Myoscape by co-immunoprecipitation of the proteins in HEK-T cells. (e) Immunoprecipitation performed with endogenous proteins isolated from mouse heart using anti-V5 (control) or anti-Cav1.2 antibody followed by immunoblotting performed with Myoscape antibody, indicates the physiological interaction between Cav1.2 and Myoscape. (f–g) Confocal Immunofluorescence analysis of Myoscape expression in isolated adult rat ventricular myocytes shows a striated signal. Myoscape is localized to couplons near the sarcomeric z-band/t-tubule interface, as evidenced by coimmunostaining of Myoscape and actinin 2 and LTCC and RYR2. Scale bars, 20 μm.