Figure 5.

R1 and R2 element pairs are required for alternate splicing of unc-17 and cha-1 transcripts. Left (A–F): Wild-type R1 and R2 elements are indicated as red and blue arrows, respectively, and scrambled elements as red and blue “tennis racquets.” Center: Confocal images of transgenic L1 animals, each carrying the dual-reporter construct diagrammed to its left. Green is GFP (corresponding to unc-17) and red is mCherry (corresponding to cha-1). Animals were imaged so that the wild-type ratio of red to green fluorescence (R/G) was ∼1.0. Anterior is to the left, and ventral is down. Bar, 10 μm. Right: Ratio of red to green fluorescence for the transgenic animals shown, presented as the mean ± SD of two to four individuals of each strain. Additional details are in Materials and Methods.