Figure 6.

Expression Analysis of the As(V)-Responsive Genes ASI3 and ASI4.

(A) RNA gel blot analysis of plants grown for 7 d on medium containing 1 mM Pi (+P), transferred to Pi-deficient medium (−P) for 3 d, and finally transferred to −P medium supplemented with either 30 μM As(V) (AsV), 50 μM Cd (Cd), or 50 μM Ni (Ni) for 8 h.

(B) and (C) Gel blot (B) and densitometry analysis (C) of dose-dependent expression of ASI3 (continuous line) and ASI4 (dashed line) in wild-type (white circles) and pht1;1-3 (black squares) plants. Seedlings were grown for 5 d on medium with 30 μM Pi (0) and then transferred to the same medium supplemented with 15, 30, or 50 μM (increasing slope) As(V) (AsV) or As(III) (AsIII) for 8 h. All intensity levels in (C) are represented as relative to 0 levels for each gene and genotype.