Figure 3.

The LZA element was sufficient to mediate transcriptional activation in response to zinc deficiency in a heterologous promoter. (A) Diagrams (not to scale) of the pes-10 promoter (black line). Boxes show the LZA1 element (blue), the LZA2 element (red) and the coding region of green fluorescent protein with a nuclear localization sequence (green). (B) A mixed stage population of transgenic animals containing multicopy arrays of the reporter constructs were cultured on medium with 40 μM TPEN to induce zinc deficiency or control, zinc replete medium (0 μM TPEN). GFP mRNA levels were analyzed by qRT-PCR. Bars depict the change in mRNA levels as the ratio between 40 and 0μM TPEN, with positive values indicating transcriptional activation in zinc-deficient conditions. Values represent the average and standard deviation of 3 independent biological replicates (*P < 0.01). (C) Images show transgenic animals at the young adult stage cultured with 0 or 40 μM TPEN; bright field images (left) show worm morphology, and fluorescent images (right) show GFP fluorescence. GFP signals were captured with identical settings and exposure times. Green puncta are the nuclei of intestinal cells. Scale bar indicates 100 μm.