Fig. 5.

Partial rescue of otic phenotypes Spry1 ^−/− ; Spry2 ^−/− mutants by reducing the dosage of β-catenin. a – c In situ hybridization analysis to detect Pax8 expression in the otic placode (outlined with white dots). c No rescue of otic placode expansions were observed in Spry1 ^−/− ; Spry2 ^−/− ; β-catenin ^−/+ embryos, as indicated. d – f In situ hybridization analysis to detect Foxi2 expression in epidermal/epibranchial cells surrounding the otic placode. The Foxi2-negative, otic region is outlined with white dots. f A Spry1 ^−/− ; Spry2 ^−/− ; β-catenin ^−/+ embryo in which the Foxi2 expression pattern appeared more similar to normal control embryos (d), rather than Spry-deficient embryos (e). The percentage of Spry1 ^−/− ; Spry2 ^−/− ; β-catenin ^−/+ embryos with partial rescue of the Foxi2 expression pattern is indicated. g – i E-cadherin antibody stain on whole-mount embryos to reveal the extent of closure of the otic cup. i A Spry1 ^−/− ; Spry2 ^−/− ; β-catenin ^−/+ embryo in which the otic cup is more closed than any Spry-deficient control (see H). The percentage of Spry1 ^−/− ; Spry2 ^−/− ; β-catenin ^−/+ embryos in which otic cup closure was partially rescued is indicated. j Average anterior-posterior lengths. Only the subset of Spry1 ^−/− ; Spry2 ^−/− ; β-catenin ^−/+ embryos in which Foxi2 expression domains appeared more similar to normal were selected for length measurement. Scale bar (a – f), (g – i), 100 μm