Contains a 5.2kb genomic fragment including the 55.1 and 53.1 alternative exons 5. These transcribe in opposite directions (towards each other), and their 3' UTRs overlap. 2kb of sequence upstream of 53.1 and 1.2kb of sequence upstream of 55.1 is included. Just before the 55.1 stop codon EGFP (tag1) has been inserted, however this allele contains a frame shift mutation at amino acid 499, preventing expression of the fusion protein. Just before the 53.1 stop codon a Tag:FLAG (tag2) has been inserted. This 5.2kb fragment is driven by UASt sequences, in the orientation 53.1-tag1-tag2-55.1.