Salicylic acid induces the proton conductance in the inner mitochondrial membrane of lupine cotyledons

Effects of Salicylic Acid on the Metabolism of Mitochondrial Reactive Oxygen Species in Plants

“…At the same time, high ROS and NO production, as well as enhanced lipid peroxidation and cyt c release from mitochondria were also detected after 1 mM SA treatment [91]. Similar results of SA application were measured where SA triggered the release of cyt c from the mitochondria to the cytosol in Arabidopsis cell suspension culture [101] and in soybean seedlings [112]. Cyt c release is associated not only to high ROS and lipid peroxidation and to the collapse of ∆Ψ but also to low ATP production and the elevation of Ca 2+ levels [5,47].…”

“…Significant decrease in mitochondrial ∆Ψ was also reported after SA treatment. Moreover, the degree of ∆ψ dissipation was dependent on the applied phytohormone concentration and duration on isolated mitochondria from sugar beet taproots and lupine cotyledons [90,100], as well as in cell suspension cultures of Rubus fruticosus [96] and Arabidopsis leaves [101] or in protoplasts [8]. ROS-dependent disruption of mitochondrial morphology and collapse of ∆Ψ are associated with the formation of PTP [102].…”

“…Loss of mitochondrial integrity and cyt c release from mitochondria takes place before cell death execution [45,92]. This cyt c release can activate various cysteine proteases in the cytosol whose activities and the expression of its coding sequences were elevated by SA [97,101,[113][114][115][116]. Cell death in plant organs is preceded by various cytological and biochemical features ( Figure 1): specific morphological changes, rupture of vacuole membrane tonoplast, activation of proteases and nucleases, chromatin aggregation and DNA fragmentation [42][43][44][45][46]117], which hallmarks of PCD were also detected upon SA treatments [97,101].…”

Oxidative stress tolerance and salicylic acid levels in early-flowering populations derived from two cultivars of annual flax (Linum usitatissimum L.)

“…In the R cultivar populations, SA increased the oxygen consumption rate of intact leaves, as expected given its capacity to uncouple mitochondrial respiration (Shugaev et al 2016), to the same extent in both early-flowering populations and their normal-flowering controls. By contrast, in the L cultivar populations, SA decreased the oxygen consumption rate of intact leaves.…”

“…In the present study, we measured intact leaf respiration rates in the presence and absence of an uncoupling agent in order to estimate the in situ level of mitochondrial uncoupling in our plant populations. While dinitrophenol (DNP) and FCCP are considered as the "classical" uncoupling agents, we opted to use salicylic acid (SA) in the present study, which has been shown to elevate IMM proton conductance and collapse the proton gradient in leaves from other plant species (e.g., lupine; Shugaev et al 2016). We predicted that early-flowering flax populations would have a lower degree of mitochondrial uncoupling compared to their normal-flowering controls, allowing them to better synthesize ATP and, thereby, devote more energy toward their early reproduction at the expense of elevated ROS production, increased oxidative damage, and shorter lifespan.…”