Prostaglandin signal inhibition results in an expansion of the distal early domain, which is rescued by the addition of exogenous dmPGE2.
Embryos were treated with a (A) 1% DMSO control, the (B) Ptgs1 selective inhibitor SC-560 at 50 μM from 4 hpf to 24 hpf, microinjected with the ptgs1 MO alone, or microinjected with the ptgs1 MO and treated with dmPGE2 from 4 hpf to 24 hpf. Embryos were treated with the (C) Ptgs2a selective inhibitor NS-398 at 50 μM from 4 hpf to 24 hpf, microinjected with the ptgs2a MO or microinjected with the ptgs2a MO and then treated with dmPGE2 at 50 μM from 4 hpf to 24 hpf. (D) Embryos were microinjected with a combination of the ptgs1 MO and ptgs2a MO. Embryos were microinjected with (E) ptger2a MO1, ptger2a MO2, (F) ptger4a MO1 and ptger4a MO2. (A–E) WISH was used to stain for the DE (slc12a1), DL (slc12a3) (purple), and the somites (smyhc1) (red) at the 24 hpf stage. Black bars indicate segment gene expression domain. Red scale bar, 70 µm. (G) Summary depicting the nephron segments after inducing deficiency of prostaglandin synthesis or receptor activity.