Fig. 4. Cellular localization of GFP-tagged MyBPs and MyHC. COS cells were transiently transfected with GFP/C (A,D,G,J), GFP/C7-10 (B,E,H,K) and GFP/H (C,F,I,L). Cells were transfected either singly (A-C) or with MyHC (D-L). GFP/C (A,D) GFP/C7-10 (B,E) and GFP/H (C,F) protein expression was detected by direct fluorescence using fluorescein excitation and emission filters. Expression of MyHC was detected by indirect immunofluorescence using F59 (G-I). The overlap of GFP-tagged MyBPs and MyHC is shown in the bottom panels (J-L). Cells transfected singly with GFP-tagged MyBPs exhibit a diffuse distribution (A-C). Co-transfection of GFP/C (D, G and J) GFP/C7-10 (E, H and K) or GFP/H (F, I and L) and MyHC induce copolymer cable formation in the COS cells.