Figure 2.

Stimulation of the enhancerless yellow gene in transgenic lines. (A) Testing the ability of the UAS promoter located at –893 to produce the functional Yellow protein. The UAS promoter is represented by the white rectangle marked ‘UAS’. The ‘yellow’ columns show the numbers of transgenic lines with different levels of body and wing pigmentation. ‘+GAL4’ indicates that yellow phenotypes in transgenic lines were examined after induction of GAL4 expression. (B) Testing the frequency of yellow stimulation in random genomic positions. For other designations, see Figure 1.