Figure 1.

Characterization of the triple mutant. A, Western-blot analysis of PHT1;1, PHT1;2, and PHT1;3 on root membrane protein extracts. No PHT1;2 or PHT1;3 proteins could be detected in pht1;1 grown in +P. Lanes were loaded with 10 or 20 μg of root proteins extracted from plants grown in –P or +P medium, as detailed in the figure. A loading control western blot, using the anti-Plasma Membrane Intrinsic Protein1 (PIP1) antibody, is shown at bottom. B, ³³P uptake capacity in +P conditions. C, ³³P partitioning (leaves [L] per total P) in +P conditions. For B and C, each bar corresponds to 22 to 24 individual plants. All experiments were performed at least twice. Error bars represent se. WT, Wild type; L+R, leaves + roots.