Fig. 1

Fig. 1 RA signaling promotes specification of posterior nkx2.5+ progenitors. (A–F) ISH for nkx2.5:Kaede (Kaede) in DMSO-treated (control) and DEAB-treated embryos at the 14s, 18s, and 20s stages (16, 18, and 19 hpf). Brackets in A and B indicate the length and width of the nkx2.5:Kaede expression. Nkx2.5 expression is expanded laterally and posteriorly and the posterior pharyngeal artery progenitors are not a distinct aggregate in RA deficient embryos. Views are dorsal with anterior up. Arrows in C and E indicate the space between the anterior nkx2.5+ and posterior nkx2.5+ aggregates. Arrows in D and F indicate the posterior limit of nkx2.5 expression and lack of posterior nkx2.5 aggregates. n ​= ​25 for all conditions examined.