Figure 3.

Disruption of MYB40 results in Arabidopsis sensitivity to As(V).

(A) Phenotypic comparison. The myb40 mutants, OE26, and WT plants were germinated and grown on ½ MS medium with or without 300 μM As(V) for 7 d, and then representative photographs were taken. Scale bar corresponds to 0.5 cm.

(B and C) Primary root length and fresh weight analysis. The myb40 mutants, OE26, and WT plants were germinated and grown on ½ MS medium containing 0, 200, 300, and 400 μM As(V) for 7 d, and then the primary root length (B) and fresh weight (C) were measured. The values are means ± SE; n ≥ 20 in (B) and n = 3 in (C).

(D and E) As and Pi content measurement. Seven-d-old seedlings were transferred to ½ MS medium with 300 μM As(V) for 3 d, then harvested for measurement of As content (D) and Pi content (E). Data are shown as mean ± SE; n = 3.

Asterisks in (B, C, D, and E) indicate significant differences compared with WT plants (^#) by Student's t-test: ∗P < 0.05, ∗∗P < 0.01.