Fig. 4.

ssrp1b, ssrp1a and ssrp1a^1-518 substitute Drosophila Ssrp function in the eye. (A-R″) For full genotypes and sample numbers, see supplementary material Table S1. (A,D,G,J,M,P) Scanning electron micrographs of leftward-facing adult female Drosophila heads. (B,E,H,K,N,Q) Confocal images of female third instar larval eye-antennal discs (ed) and brains (br) labelled with anti-PKC (blue). GFP signals indicate the areas of transgene expression, and V5 labelling (red) the presence of Danio rerio Ssrp1b-V5, Ssrp1a-V5, Ssrp1a^s819-V5 or Ssrp1a^1-518-V5. Anterior is up. (C-C″,F-F″,I-I″,L-L″,O-O″,R-R″) Eye-antennal discs and single channels of eye fields labelled with anti-Elav (red or white), visualising R-cell differentiation, and anti-PH3 (blue or white), monitoring two mitotic waves (arrowheads). (A-C″) Controls show adult eyes with a regular array of ommatidia and eye-imaginal discs with differentiated R-cells and two waves of dividing cells. (D-F″) Drosophila Ssrp knockdown causes the loss of adult eyes, and eye-antennal discs are significantly smaller (asterisk in E). (G-R″) ssrp1b (G-I″), ssrp1a (J-L″) and ssrp1a^1-518 (P-R″) expression rescues eye defects caused by Ssrp^RNAi. Expression of ssrp1a^s819 (M-O″) fails to rescue. Asterisk in N indicates eye-antennal disc defects. (F,O) Dashed lines outline eye-antennal discs.