Figure 4. Tbx5 removal does not affect cell survival in the VCS.

X-Gal– (A, B, D, and E) and acetylcholinesterase-stained (C and F) serial sections through the AV bundle of R26R^{minKCreERT2/+}Tbx5^+/+ (A–C) and R26R^{minKCreERT2/+}Tbx5^minKCreERT2 (D–F) animals administered tamoxifen showed similar distribution of cells labeling the VCS fate map, which demonstrated that Tbx5 was not required for VCS cell survival. ivs, interventricular septum. Boxed regions in A and D are shown at higher magnification in B and E. Original magnification, ×2.5 (A and D), ×40 (B, C, E, and F).