Figure 7.

Signaling pathways affected by γ-secretase. A, B, Reduced Notch1a mRNA (A) and increased β-catenin (B) immunoreactivity in 7 dpf psen1^−/− larvae when compared with WT fish. n = 6–9/group. C, D, Increased Notch1a mRNA (C) and reduced β-catenin (D) immunoreactivity at 14 dpf in psen1^−/− larvae when compared with WT fish. E, F, At 1 month of age the Notch1a mRNA expression pattern and intensity were similar in the two groups (E), whereas at ∼2.5 years the β-catenin immunoreactivity was lower in the posterior hypothalamus of the psen1^−/− animals compared with WT animals (F); n = 4–7/group in C–F.