Figure 4

In vivo Pnp5a overexpression leads to smaller (100) crystal facets. a,b) Maximum intensity projections of larval eyes highlighting iridophore reflection upon heat‐shock overactivation of Pnp5a transgene (hsp70:Pnp5a‐GFP, green) (b‐b’) or in heat‐shocked sibling controls (a‐a’), at 72 hpf. In both cases, iridophores are labeled by the 2.7kb‐tfec:mKate2 (magenta) reporter line. Insets (a″‐b″) highlight respective crystal morphologies. c,d) Maximum intensity projections of larval eyes highlighting iridophore reflection in Pnp5a homozygous mutants (Pnp5a^−/−, d‐d’) or in wildtype controls (c‐c’), at 72 hpf. In both cases, iridophores are labeled by the TDL358:GFP (green) reporter line. Insets (c″‐d″) highlight respective crystal morphologies. Scale bars: 50 µm (a–d), 5 µm (a″‐d″). e,f) Comparison of the average iridophore reflection per 50 µm in different WT, Pnp5a overexpression (e) or mutant conditions (f), at 72 hpf. au, arbitrary units. Mean ±SEM are shown in black. Heat‐shock sibling control, N = 5; Pnp5a overexpression, N = 10; WT, N = 10; Pnp5a^−/−, N = 15. Asterisks indicate p‐values of two‐tailed, non‐parametric Welch t‐tests between groups: ^∗p < 0.05, ^∗∗p < 0.01.