Whole mount transgenic embryos containing one of the multimerized synthetic reporter constructs were labeled with anti-GFP (green; B, D, F, H, J, L, N, P, R, T, V, X, Z, B’, D’, F’, H’, J’, L’, N’, P’, R’, T’, V’, X’, Z’, B’’ and D’’) and anti-sim (red; C, G, K, O, S, W, A’, E’, I’, M’, Q’, U’, Y’ and C’’) antibodies and analyzed by confocal microscopy. The overlap in expression between GFP and sim is yellow (merge; A, E, I, M, Q, U, Y, C’, G’, K’, O’, S’, W’ and A’’). Midline GFP expression is driven by the (A–D) synth 1:GFP, (E–H) synth 2:GFP (I–L) synth 3:GFP, (M–P) synth 4:GFP and (Q–T) synth 5:GFP, whereas the (U–X) Sox:GFP and (Y–B’) synth 6:GFP reporters are not expressed in either the midline or trachea. The (C’-F’) Toll:GFP, (G’-J’) synth 7:GFP, (K’-N’) synth 8:GFP, (O’-R’) synth 9:GFP and (S’-V’) synth 10:GFP synthetic reporters are expressed in both the midline and trachea, whereas the expression pattern of the (W’-Z’) synth 11:GFP and (A’’-D’’) synth 12:GFP reporters are restricted to trachea only. The expression patterns of the Toll:GFP and Sox:GFP reporters were previously reported [59]. Note that midline GFP expression driven by the (A–D) synth 1:GFP, (M–P) synth 4:GFP, (Q–T) synth 5:GFP, (C’-F’) Toll:GFP, (G’-J’) synth 7:GFP, (O’-R’) synth 9:GFP and (S’-V’) synth 10:GFP reporters is in both neurons and glia, whereas expression driven by the (E–H) synth 2:GFP reporter is restricted to midline glia and expression of the (I–L) synth 3:GFP and (K’-N’) synth 8:GFP reporters is restricted to midline neurons. The immediate CME context within each synthetic sequence is indicated to the left of the images and the entire sequence of each synthetic reporter construct is listed in Table 4. Arrows indicate midline glia and arrowheads indicate midline neurons. Lateral or ventrolateral views of stage 16 transgenic embryos are shown; anterior is in the top, left hand corner and ventral is bottom, left. Four copies of each synthetic sequence were tested within the reporter constructs.