Fig. 5. Sex-non-specific alternative splicing of retn. (A) A lack of sex-specific splicing of retn. RNAs from CNS tissue from late third instar larvae (lanes 1, 2, 5, 6, 9, 10) and mid-stage pupae (lanes 3, 4, 7, 8, 11, 12) from both sexes were analyzed by RT-PCR probing exons 1 to 4 (lanes 1 to 4), 4 to 8 (lanes 5 to 8), and 8 to 11 (lanes 9 to 12). The splice variant of retn joining exon 1 to 4 is present at very low levels and migrates beyond the level shown. (B) An abundant splice variant of retn joining exon 1 to 6 is present in both sexes. RNAs from CNS tissue from mid-stage pupae of both sexes were analyzed as above (A), probing between exons 1 and 8 (lanes 1 and 2), and 4 and 11 (lanes 3 and 4). The faster migrating band in lanes 1 and 2 represent splice variant 1-6.