Fig. 2. Sequence requirements for ACE3 function in amplification. (A) The BP construct and ACE3 deletion mutants. For convenience, ACE3 (751 to 1071 in Fig. 1) is numbered from 1 to 320. The shaded regions are conserved among four Drosophila species. The region was identified by sequence analysis and has homology to the ß region in ori-ß. The two Myb consensus binding sites are indicated by stars with one of them outside the conserved shaded regions. The three p120-binding regions are indicated by black bars, the sizes of which are not to scale (Beall et al., 2002). (B) Southern blot analysis of amplification levels for representative independent transgenic lines. BP and ACE3 total deletion (AD) lines were analyzed as controls in the same experiment. rDNA was used as the loading control. (C) Quantitation of three independent assays for each independent transgenic line according to the measurement of amplification levels in Materials and methods. Average and standard deviation are presented in the bar graph. The average fold amplification level is given below the name of the construct. P values are presented for a comparison of each construct to BP using unpaired, two-sided t-tests.