Loss of phosphoribosyl pyrophosphate synthetase (PRPS) filaments results in lens fiber disorganization. A, Representative maximum intensity projections of confocal images from wild‐type, prps1a mutant, and prps1b mutant eyes at 5 dpf, stained with PRPS (green) and rhodamine phalloidin (red). Rostral is to the left and dorsal is to the top; zoomed views of boxed areas from the first column are displayed in the following columns. Fractions indicate the number of embryos exhibiting a regularly‐spaced, lattice‐like actin array in the lens out of the number of embryos examined per genotype. While both prps1a mutants displayed abnormal PRPS signal in the lens, only prps1asd59 mutants exhibited a disorganized actin array in the lens fibers. Scale bars: 40 μm for first column, 20 μm for zoomed images. B, Representative maximum intensity projections of confocal images from wild‐type and prps1amutant eyes at 2 dpf, stained with rhodamine phalloidin. Rostral is to the left and dorsal is to the top; zoomed views of boxed areas are displayed below each panel. Arrows indicate lens fibers. Fractions indicate the number of embryos exhibiting a honeycomb‐like actin array in the lens out of the number of embryos examined per genotype. No defects were observed in prps1asd59 mutants at 2 dpf. Scale bars: 40 μm for main images, 10 μm for zoomed images. C, Graph plots the angles between adjacent radial actin cables in the lens fibers of one wild‐type and one prps1asd59 eye at 5 dpf. Red lines indicate median values. Although the distribution of angle sizes is much broader in the prps1asd59 eye, there is not a statistically significant difference between these data sets (ns, not significant). D, Graph plots the average angle size observed in each wild‐type, prps1a mutant, and prps1b mutant eye at 5 dpf. Red lines indicate median values. Average angle size is similar for all genotypes (ns, not significant). E, Graph plots the SD of the actin cable angles measured in each wild‐type, prps1a mutant, and prps1bmutant eye at 5 dpf. Red lines indicate median values. Wild‐type, prps1asd60, and prps1bsd61embryos displayed small SDs in angle size, whereas prps1asd59 embryos had much higher SD values, indicating the relative disorganization of the actin cable array in prps1asd59 mutants (****P < 0.0001; ns, not significant)
