A tubulin promoter drives expression of a VP16(AD)::Zip+ hemidriver (component of a 'split driver' system, contains the VP16 activation domain).
2A-GAL4(DBD)::Zip- is introduced into the attP site in the TI{TI}unc-4FRT progenitor. The Trojan insertion introduces a stop codon, truncating the unc-4 protein after its first exon.