Figure 5. Zap1 regulation of ZRG17 expression is important to ER function.

A) ZRG17 mRNA levels were analyzed by S1 nuclease protection assay of RNA isolated from wild-type (DY1457), a chromosomal ZRG17 ZRE mutant (zrg17-1^m2ZRE), and reconstructed wild-type ZRE (ZRG17^rZRE) cells grown in LZM supplemented with 1000 μM ZnCl₂ (+) or 1 μM ZnCl₂ (−). CMD1 was used as a normalization control. The data shown are representative of two independent experiments. B) Wild-type (DY1457), zrg17Δ mutant (DY1457 zrg17Δ), chromosomal ZRG17 ZRE mutant (zrg17-1^m2ZRE), and reconstructed wild-type ZRE (ZRG17^rZRE) cells were grown in SD liquid medium overnight. Cultures were then diluted in fresh medium, and 5-μl volumes containing 10⁴, 10³, and 10² cells (from left to right) were plated onto YPD (YP medium + 2% glucose) and YPGE (YP medium + glycerol and ethanol) plates. The plates were incubated at 30 or 37°C and photographed after 3 days. C) UPRE-lacZ activity (pMCZ-Y) was assayed in the same cells as in panel B grown in LZM supplemented with 0.3 μM ZnCl₂, 3 μM ZnCl₂, and 100 μM ZnCl₂. The data shown are the means of three independent cultures for each condition and are representative of two independent experiments. The error bars represent ± 1 S.D. Letters denote statistically significant differences of UPRE-lacZ activity between strains and growth conditions (P < 0.05).