Fig. 6. Cardiomyocytes that undergo blastema-induced re-programming transiently express blastema cell markers and activate focal adhesion kinase at later stages. (A-L,N-P) Immunofluorescence staining of DiI-labeled cardiomyocytes (red) with vimentin (A,B,F,G,K,L), the blastema cell marker 22/18 (C,D,H,I,N,O) and FAK-Tyr397-P (E,J,P) 1 day and 30 days after transplantation. Bound antibodies on cryosections were detected with FITC-conjugated secondary antibody (green). Hoechst 33342 counterstaining was used to label all nuclei on the sections. Notice that, vimentin and 22/18 are expressed 1 day but not 30 days after transplantation. Activation of FAK occured simultaneously in transplanted and neighboring cells indicating successful integration into the recipient tissue. Bars, 50 µm.