(A) The genomic locus containing the dLMO gene. Three EP lines (1306, 1383, and 1394) contain insertions upstream of the first exon of dLMO. Two alternatively spliced transcripts, dLMOa and dLMOb, are reported (16). Beadex alleles Bx1, Bx3, and BxJ contain insertions (arrowhead) in the last exon of dLMO, within the 3′ UTR, between two BamHI sites. (B) Genomic Southern analysis of Beadex alleles. Genomic DNA from y w, Bx1, Bx3, and BxJ adult flies was digested with BamHI. The Southern was probed with a 403-bp BamHI fragment from the 3′ UTR of the dLMO cDNA. The 403-bp fragment is detected in DNA from y w flies (arrow) while larger fragments are detected in the DNA from Bx flies.