Dyn2 enriches at myoblast fusion site. (A) Dyn2-GFP and actin-based finger-like structures in differentiated myoblasts. Differentiated C2C12-expressing Dyn2-GFP and mCherry-actin was fixed and imaged with z-stack confocal microscopy. Maximum-intensity projections are shown, while magnified insets are single focal images. Scale bars (black and white), 10 µm. (B) Dyn2-GFP enrichment at the site of myoblast fusion. The dynamic localization of Dyn2-GFP in day 3 differentiated C2C12 was monitored with time-lapse microscopy. Five frames right before and after myoblast fusion from a 5-h recording were extracted and shown. Boxed regions were enlarged and shown in insets. Scale bars (black and white), 10 µm. (C) Dyn2-rich membrane protrusion in second-phase myoblast fusion. Time-lapse microscopic imaging of Dyn2-GFP in day 4 differentiated C2C12. Phase-contrast image was pseudocolored to better observe the boundary between two myotubes. White arrowheads indicate the Dyn2-GFP foci at the fusion interface. Black bar, 20 µm. White bar, 10 µm.