Fig. 3.

Fig. 3.

wnt9a and wnt9b are induced in distal tubules and collecting ducts after injury. (A,B) Whole-mount in situ hybridization for wnt9a. (A) wnt9a is expressed at very low levels in uninjured adult kidney tubular epithelium. (B) By 7 dpi, wnt9a is strongly induced in the branched distal tubule segments of nephrons. (C) wnt9b is expressed at low levels in uninjured adult kidney tubular epithelium. (D) After 7 dpi, wnt9b is strongly induced in the branched distal tubule segments of nephrons (DT; arrowheads) and common collecting ducts (CDs; arrow). (E) DIC image of a section through a 7 dpi kidney showing wnt9b expression in cross-sections of tubular epithelium. (F) Higher-magnification image of boxed area shown in E with wnt9b expression in a lengthwise section of tubule. (G) Quantification by qPCR at the indicated time points after injury shows that wnt9b expression was increased by 3 dpi and peaked at 5 dpi. Data derived from three individual fish per time point as indicated by individual graph symbols. Data are mean±s.d. (H) Confocal stack projection of Tg(lhx1a:GFP)×Tg(slc12a3:mCherry) transgenic kidney tissue. lhx1a:GFP nephron aggregates form exclusively on slc12a3:mCherry-positive distal tubules. Representative images from n=2 (A), n=3 (B), n=6 (C), n=4 (D), n=3 [H, Tg(lhx1a:GFP)×Tg(slc12a3:mCherry)] fish per condition. Scale bars: 0.2 mm in A-F; 10 µm in H.