7.4kb BamHI fragment containing ChAT 5' flanking region, transcription start site and 391bp of non coding sequence present in the first exon drives expression of Ecol\lacZC4.Adh.
In adult optic lobe, appears to be expressed in the same cells as Cha protein, but in the entire cell (including soma), whereas Cha protein is detected only at the nerve endings in the neuropil (thus expression appears to be more extensive).