Table 2.

Transcript levels of glutathione (GSH)-related genes in leaves and roots of Arabidopsis thaliana plants grown under control conditions (0 μM CdSO₄) or exposed to 5 μM CdSO₄ during 2 h, 4 h, 6 h and 24 h after 3 weeks of growth. For each time point, data are given as the mean ± S.E. of four biological replicates relative to the control set at 1.00. Significant differences (t-test: p < 0.05) between control and exposed plants, within each time point, are marked in colour (upregulated: ). GSH1: γ-glutamylcysteine synthetase; GSH2: GSH synthetase; GR1: glutathione reductase; GGT1: γ-glutamyl transpeptidase 1; ZAT6: zinc finger of Arabidopsis thaliana 6.

GSH-Related Genes
Gene	[CdSO4]	2 h	4 h	6 h	24 h
Leaf
GSH1	0 µM	1.00 ± 0.16	1.00 ± 0.06	1.00 ± 0.13	1.00 ± 0.04
	5 µM	0.75 ± 0.13	0.91 ± 0.05	0.79 ± 0.12	1.77 ± 0.19
GSH2	0 µM	1.00 ± 0.06	1.00 ± 0.04	1.00 ± 0.06	1.00 ± 0.04
	5 µM	0.77 ± 0.11	0.91 ± 0.10	0.90 ± 0.06	2.74 ± 0.14
GR1	0 µM	1.00 ± 0.04	1.00 ± 0.07	1.00 ± 0.20	1.00 ± 0.10
	5 µM	0.81 ± 0.08	1.05 ± 0.08	0.87 ± 0.13	3.15 ± 0.52
GGT1	0 µM	1.00 ± 0.26	1.00 ± 0.06	1.00 ± 0.27	1.00 ± 0.10
	5 µM	0.82 ± 0.12	1.34 ± 0.19	1.47 ± 0.43	4.60 ± 0.85
ZAT6	0 µM	1.00 ± 0.20	1.00 ± 0.22	1.00 ± 0.08	1.00 ± 0.30
	5 µM	0.93 ± 0.14	1.14 ± 0.28	1.55 ± 0.09	15.06 ± 0.55
Root
GSH1	0 µM	1.00 ± 0.22	1.00 ± 0.16	1.00 ± 0.10	1.00 ± 0.17
	5 µM	2.08 ± 0.45	1.35 ± 0.05	1.63 ± 0.06	4.67 ± 0.28
GSH2	0 µM	1.00 ± 0.15	1.00 ± 0.11	1.00 ± 0.01	1.00 ± 0.09
	5 µM	1.67 ± 0.01	1.31 ± 0.11	1.44 ± 0.08	2.85 ± 0.20
GR1	0 µM	1.00 ± 0.13	1.00 ± 0.02	1.00 ± 0.04	1.00 ± 0.04
	5 µM	1.01 ± 0.09	0.88 ± 0.07	1.36 ± 0.03	2.06 ± 0.19
GGT1	0 µM	1.00 ± 0.16	1.00 ± 0.14	1.00 ± 0.07	1.00 ± 0.13
	5 µM	1.72 ± 0.11	1.67 ± 0.12	2.00 ± 0.26	5.07 ± 0.02
ZAT6	0 µM	1.00 ± 0.16	1.00 ± 0.13	1.00 ± 0.16	1.00 ± 0.15
	5 µM	1.10 ± 0.19	1.29 ± 0.21	1.94 ± 0.02	2.89 ± 0.55