Figure 3: Tbx4 rescues muscle patterning of Pitx1−/− hindlimbs.
From: Divergent transcriptional activities determine limb identity
Front (a–d) and lateral (g–j) views of hindlimbs from e14.5 embryos stained by whole-mount immunohistochemistry for myosin heavy chain. The lower leg (zeugopod) muscles of (a, g) Pitx1+/+, (b, h) Pitx1−/−, (c, i) Pitx1−/−;Prx1-Tbx4 and (d, j) Pitx1−/−;Prx1-Tbx5 HL are highlighted and colour coded in the drawings. Lighter colours in b, d, h and j reflect muscle assignment by analogy in mutants with altered patterning. (e, f) Optical projection tomography (OPT) of wild-type e14.5 (e) HL and (f) FL muscles is depicted by colour-coded identification. In the lower part below the dotted line, EDL or EDL+C was removed to visualize the underlying EDB or EIP. (k, l) Lateral OPT views of HL and FL. Dotted arrows indicate TA (e) and ECR (f), whereas full arrows point to EDB (in HL, e) and EIP (in FL, f). Analogy between HL and FL muscles is based on comparative studies28,39. OPT pictures were generated using J Atlas View (http://www.nimr.mrc.ac.uk/3dlimb/)25,26.
