Figure 2.

Knockdown of STIM2 in mouse primary skeletal myotubes. (a) Three different forms of siRNA were used to knock down STIM2 in mouse primary skeletal myotubes. The lysate of the STIM2-knockdown myotubes (50 μg of total protein) was subjected to immunoblot analysis with anti-STIM2 antibody (upper panel). α-actin and Coomassie Brilliant Blue staining were loading controls. #3 siRNA knocked down STIM2 more effectively compared with others (up to 90%). Untransfected control and scrambled siRNA-transfected myotubes were used as negative controls. The immunoblot data were cropped from the immunoblot images of different gels and were grouped. The full-length blots are presented in Supplementary Fig. 5. Three independent experiments were conducted. (b) The STIM2-knockdown myotubes with #3 siRNA show normal myotube formations, and are indistinguishable from the untransfected or the scrambled siRNA-transfected control. ‘Immature myotubes on D3’ means untransfected immature myotubes on differentiation day 3 (left). ‘Myotubes on D5’ means untransfected, scrambled siRNA-transfected, or STIM2-knockdown myotubes on differentiation day 5. The bar represents 50 μm.