ac enhancer sequences regulate expression of a VP16(AD)::Zip+ hemidriver (component of a 'split driver' system, contains the VP16 activation domain).
Hsim\VP16AD.ac, KrUAS.cHa, Scer\GAL4DBD.gsb, Scer\GAL4KZip+.R25A05, pdm2UAS.Tag:HA has motor neuron phenotype
"Split GAL4" system construct.