WISH was used to assess epithelial specification and segment pattern using antisense riboprobes (purple) in wild-types (left column) and prkcι/ζ morphants (right column). (A,B) In control and prkc ι/ζ morphants the proximo-distal specification of nephron segments was normal. (Lateral views, anterior to the left) (A) Podocytes were labeled with nephrin, the proximal straight tubule (PST) with trpm7, and distal late tubule (DL) with slc12a3. (B) Podocytes were labeled with wt1b, the proximal convoluted tubule (PCT) with slc20a1a, and the distal early tubule (DE) with slc12a1. (C) In prkcι/ζ morphants the PCT failed to undergo proper morphogenesis and instead remained linear, while the PCT segment in control wild-type embryos at 48 hpf and 72 hpf underwent progressive coiling morphogenesis. (Dorsal views) (D) Acridine orange labeling indicates cell death in the PCT segment of the pronephros (white arrows) in prkcι/ζ morphants, but not wild-types. (Lateral views, anterior to the left)