||Fig. 2. Tbx5 is required for lung development in mice and frogs.
(A) RNA ISH for Nkx2-1 in E9.5 Tbx5+/+ and Tbx5−/− embryos. The PE, inflow tract (IFT), and cardiac ventricle (V) are labeled.
(B) Histology from both sagittal and coronal perspectives (Left) and 3D reconstruction (Right) of E10.5 lungs from Tbx5+/+ and Tbx5−/− embryos. Black and red arrows point to the lung bud (LB) branches or lack of branches off the foregut.
(C) ISH stains of Tbx5 across vertebrate species. Arrows indicate expression in the mesodermal derivatives surrounding the PE.
(D, Upper) Strategy for generating biallelic frameshift mutations using sgRNA targeted to the fifth exon of X. tropicalis to disrupt the T-box domain. (Lower) Examples of sequences recovered from tbx5 FS mutants. (E and F) RNA ISH of NF35 tadpoles for nkx2-1 in wild type and tbx5 FS mutants (E) and tadpoles injected with mismatched morpholinos (MM-MOs), tbx5-MOs, or tbx5-MOs cotreated with BIO (F). (G) Live images (Left) and H&E-stained transverse sections (Right) of NF42 tadpoles, depicting anatomical defects induced by CRISPR-mediated mutation of tbx5.