Fig. 3. In vivo fate mapping of Meis-overexpressing cells in limb regenerates. (A) Constructs used for electroporation. (B,C) Immunohistochemistry on blastema sections 1 (B) and 6 (C) days after electroporation; Meis (red), GFP (green), nuclei (blue). (D-I) Time-lapse analysis of electroporated cells during proximal limb regeneration. Early bud mid-humerus blastemas electroporated with GFP (D-F) or Meis1+Pbx1+GFP plasmids (G-I) at different times post-electroporation. White lines indicate the amputation plane; white arrows, the limit between mesenchyme and the ectodermal cap; black arrow in H, the distal-most position of electroporated cells. (J,K) Diagram of the relative contribution of electroporated cells to the PD segments (indicated at left). (J) Proportions relative to the total number of cells scored in each condition; (K) proportions relative to the total number of cells observed in control limbs. The construct combinations used are indicated above. The solid red line indicates the percentage of electroporated cells contributing to regions proximal to mid-zeugopod in controls; the dotted red line indicates this percentage in different experimental conditions. dz, distal zeugopod; pz, proximal zeugopod; ds, distal stylopod.