Figure 3.

Daam1 knockdown reduces the expression of late pronephric markers of differentiation and morphogenesis in Xenopus. (A) Diagram of Xenopus pronephric kidney showing positions of proximal tubules, distal tubules, collecting duct, and glomus. (B through F) The left V2 blastomere of eight-cell stage embryos was injected with 20 ng of Std MO or Daam1 MO. Embryos developed until stage 38 to 40 and were analyzed for nphs1, clckb, slc5a1, and atp1a1 expression levels on their injected (left) side as compared with their uninjected (right) side. (B) The fraction with reduced nphs1 marker expression on the injected side as compared with the uninjected side for Daam1-MO-injected animals was similar to that of Std-MO-injected controls, whereas the fraction with reduced clckb, slc5a1, and atp1a1 expression on the injected side as compared with the uninjected side for Daam1-MO-injected animals is greater than that for Std-MO-injected controls. (C) Injected sides of Std-MO- and Daam1-MO-injected animals do not have reduced nphs1 expression. (D) Injected sides of Std-MO-injected animals do not have reduced clckb expression, whereas injected sides of Daam1-MO-injected animals have significantly reduced clckb expression. (E) Injected sides of Std-MO-injected animals do not have reduced slc5a1 expression, whereas injected sides of Daam1-MO-injected animals have significantly reduced slc5a1 expression. (F) Injected sides of Std-MO-injected animals do not have reduced atp1a1 expression, whereas injected sides of Daam1-MO-injected animals have significantly reduced atp1a1 expression. (C through F) Bars are 500 nm.