Figure 1.

Nia mRNA accumulation in the different nonsilenced scions (a) wild-type plants (WT) and homozygous transgenic plants over-accumulating Nia mRNA caused by the presence of the 35S-Nia2 transgene (classes I and II). (b) Wild-type plants (WT) and NR- or NiR-deficient plants over-accumulating host Nia mRNA caused by metabolic derepression (class III). Ten micrograms of total RNA extracted from leaves were probed with the tobacco Nia2 cDNA. Photographs of the 25S rRNA band in the ethidium-stained gel indicate the amounts of RNA loaded in each lane.