FIGURE 4.

ChACBP1 expression under abiotic stresses as detected by Northern blot analysis with digoxigenin-labeled ChACBP1 cDNA probe. (A) Northern blot analysis using total RNA (3 μg) extracted from Chlorella cells treated with 200 mM NaHCO₃, 200 mM NaCl, 2 mM H₂O₂, 100 μM CuCl₂, or low temperature (4°C) at indicated time points. (B) Northern blot analysis using total RNA (3 μg) extracted from Chlorella cells treated with different concentrations of NaHCO₃ (0, 50, 100, 200, 300, and 400 mM); NaCl (0, 50, 100, 150, 200, and 300 mM); H₂O₂ (0, 1, 2, 3, 4, and 5 mM); CuCl₂ (0, 50, 100, 200, 300, and 500 μM); or different temperatures (24°C, 18°C, 16°C, 14°C, 10°C, and 4°C). All samples were collected at 6 h of treatment.