Figure 3(e) shows the selleck CHIR99021 location of ONOO? in the control roots of Arabidopsis seedlings with very slight fluorescent signal. However, this RNS significantly increased in roots under salinity stress with a homogeneous distribution throughout the root (Figure 3(f)), similar to the distribution of the NO.Figure 3Representative images illustrating the CLSM in vivo detection of superoxide radical (O2??) ((a) and (b)), nitric oxide (NO) ((c) and (d)), and peroxynitrite (ONOO?) ((e) and (f)) in root tips of Arabidopsis seedlings exposed to …3.3. Effect of Salinity on NADP-Dehydrogenase ActivitiesThe analysis of the activity of the main NADP dehydrogenases is shown in Figure 4(a). The activity of NADP-ICDH, ME, and G6PDH increased 1.6-, 1.5-, and 1.9-fold, respectively, with respect to control seedlings.

However, the 6PGDH activity was not affected by salinity treatment. Considering that the NADP-ICDH showed a higher relative specific activity under salinity conditions in comparison to the other NADP dehydrogenases, further analyses were focused on this enzyme.Figure 4(a) Activity of NADP-isocitrate dehydorgenase (ICDH), malic enzymes (ME), glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in Arabidopsis seedlings exposed to 100mM NaCl. (b) Representative agarose electrophoresis gel of …Arabidopsis has several NADP-ICDH isoforms localized in different subcellular compartments including the cytosol, chloroplasts/mitochondria and peroxisomes [20]. For an evaluation of the potential contribution of each isoform under salinity stress, its gene expression was analyzed.

Figure 4(b) showed the gene expression of the cytosolic (At1g65930), chloroplastic/mitochondrial (At5g14590) and peroxisomal (At1g54340) NADP-ICDH evaluated by semiquantitative RT-PCR. Contrary to what happened in the activity analysis, none of the genes appeared to undergo significant changes Entinostat under salinity stress. With the goal of gaining fuller knowledge of the potential function of the NADP-ICDH activity, its activity was investigated independently in roots and leaves of Arabidopsis seedlings after 100mM NaCl treatment (Figure 4(c)). NADP-ICDH activity was found to be higher in roots than in leaves from control plants. Also, it was observed that, under salinity conditions, the activity significantly increased (by 39%) in roots whereas the activity in leaves showed no change.4. DiscussionSalinity is recognized to influence plant productivity due to its negative effects on plant growth, ion balance, and water relations. In addition, in many plant species such as pea [4, 5], tomato [36, 37], or olive [30], the salinity stress is usually accompanied by an oxidative stress.