Table 1.

The Induction of H₂O₂-Responsive Genes in Wild-Type and phb3-3 Roots after H₂O₂ Treatment

	WRKY6	HSFA4	TCH3	GSTU12
Wild type	7.1 ± 0.8	8.9 ± 0.7	27.6 ± 3.8	13.4 ± 2.3
phb3-3	7.9 ± 0.6	8.6 ± 0.8	25.0 ± 2.9	13.6 ± 1.7

The roots of 7-d-old seedlings grown hydroponically in half-strength MS were treated with 0.5 mM H₂O₂ for 0.5 h. RNA was extracted from the roots, and then mRNA levels were determined by quantitative RT-PCR. The gene UBA (ubiqitin-associated/TS-N domain-containing protein; At5g12120), which showed no response to H₂O₂ treatment, was used as an internal control. The four tested genes have the same mRNA levels in wild-type and phb3-3 roots in the absence of H₂O₂. Fold induction values were determined as the ratio of treated versus control root mRNA levels with sd (n = 3).