Genomic fragment including the E(spl)mβ-HLH gene, from BAC clone CH322-115N23. A sfGFP-Tag:FLAG-Tag:CS(PSP)-Tag:CS(TEVp)-Tag:BLRP tag cassette has been introduced at the C-terminal end of the E(spl)mβ-HLH gene, such that protein isoforms are tagged.