Figure 5.

Immunoblot for NRT2.1 (A, C, and E) and NAR2.1 (B, D, and F) using microsomes from roots of wild type (WT) and the transgenic line L5. A and B, Plants were grown in vitro during 8 d on 0.2 mm KNO₃ and treated during 4 h by the addition of 2 mL of a 250 mm NH₄NO₃ solution to reach a final concentration of 10 mm NH₄NO₃. C and D, Plants were grown in vitro for 8 d on 0.2 mm KNO₃ as N source and harvested after 14 h of light or 10 h of light + 4 h of darkness. E and F, Plants were grown in vitro for 7 d on 0.2 mm KNO₃ as N source and transferred, after 8 h of light, either in continuous dark or in continuous light for 24 h. Samples were separated on a 11% SDS-PAGE gel (12 μg protein/lane).