Single-nucleus transcriptomics of wing sexual dimorphism and scale cell specialization in sulphur butterflies
Fig 2
DsxF blocks UV-iridescence in females in a cell-autonomous fashion.
A. Effects of Dsx mosaic knock-outs (mKO), as seen in comparisons of female and male WT individuals with representative Dsx G0 crispants. The sex of each crispant was determined by concordant genital morphology and genotyping. Phenotypic effects are limited to the dorsal surfaces and most visible in the marginal region. B. UV-photography (320–400 nm) of UV-iridescent dorsal patterns in the same mutants, showing an ectopic gain of UVI scales in females (top). In males (bottom), the feminization of the marginal region triggers a regression of the male UVI pattern distal border. C–C′. Close-up views of the central forewing regions (same individuals as in panels A, B), including overlays of UV photographs (C′: magenta false-color) over visible light images, and highlighting the intermediate states of marginal patterns. In females: gain of UVI scales, regression of the melanic marginal patterns. In males: gain of female yellow spots in males (arrowheads), extension of the melanic marginal patterns (white arrow), and regression of the UVI field (black arrow). D. Cell autonomy of UVI scale gains in female Dsx mKOs, as shown by continuous UVI mutant clones with sharp boundaries (KO). Superimposed views of the same region, taken in visible and ultraviolet light, are shown across each diagonal line. E. RNA interference effects of Dsx siRNA electroporation in male and female forewings. Dotted lines mark the approximate areas that were electroporated. Dsx knockdown results in ectopic UVI (top), and in a feminization of the marginal pattern in males, including with a regression of medial UV iridescence at its distal border. F. High-magnification view of the female wing shown in panel E, at the interface of the treated (ectopic UVI scales) and untreated area. Scale bars: C, E = 1 mm; D = 100 μm.