Strains bearing chromosomal replacements of the stress-response genes by myc-tagged copies respond as wild type. (A) PR109 (wild type), GD1892 (wis1–12myc), GD1942 (spc1–12myc), GD1953 (pyp1–12myc), and GD1955 (pyp2–12myc) were challenged with 0.6 M KCl for 15 min and harvested, and total RNA was extracted for Northern analysis of gpd1+ mRNA. (B) Quantification of gpd1+ expression is provided for each strain. Signals were normalized relative to the leu1+ control.