Figure 6. NO effect on gene expression profiles of NO-responsive genes (NR and nitrate/nitrite transporters). Gene expression analysis was determined by qRT-PCR in leaves of Medicago truncatula Jemalong A17 plants vacuum-infiltrated with 100 μΜ and 2.5 mM SNP at 3/24 h in mature (40 d (A) and senescing (65 d (B) plants. Asterisks denote statistically different values according to pairwise fixed reallocation randomization test (p < 0.05) (n = 3).