Figure 3.

Identification of conserved motifs upstream of the cholinergic locus (unc-17/cha-1) of 10 nematode species. (A) Locations of 51 conserved motifs in unc-17 promoters derived from sequence alignments, as described in the Materials and Methods. The R1 and R2 motifs have been described previously, and regulate the alternate splicing of unc-17 and cha-1 transcripts (Mathews et al. 2015). (B) Sequence logos of the conserved promoter motifs. The small element designated E6 = AIY motif (TTX-3/CEH-10-binding site) has been functionally validated in C. elegans to be required to drive unc-17 expression in AIY by Wenick and Hobert (2004). The element designated E7 contains the consensus binding site for the UNC-86 transcription factor. The combined deletion of E6 and E7 (designated unc-17prom8_B30 in Figure 2) results in the loss of expression of the reporter in AIY and RIH. The red box in E3 indicates the nucleotides that were replaced in ot1025 (Figure 8). The red box in F2 indicates the deleted nucleotides in unc-17prom9_C39 (Figure 2).