TGase-induced Cd tolerance by boosting polyamine, nitric oxide, cell wall composition and phytochelatin synthesis in tomato

Selenium Nanoparticles Mitigate Cadmium Stress in Tomato through Enhanced Accumulation and Transport of Sulfate/Selenite and Polyamines

“…This finding is in accordance with a previous study showing that Cd increases PC synthesis via formation of a GSH–Cd complex rather than by regulating the transcription of PCS genes . Thus, the mechanism underlying the enhancement of Cd tolerance induced by SeNPs can be imputed to involve an increase in the synthesis of PCs, which are essential for Cd detoxification by complexation with toxic ions. , Indeed, loss of function of PC synthase genes in tomato and Arabidopsis exacerbates the hypersensitivity to Cd stress, while overexpression of PC-synthesis genes or activation of the GSH-dependent pathway by phytohormones or nanoparticles can increase Cd tolerance . The SeNPs-induced Cd accumulation in the roots is in line with more PCs, which enhanced the Cd storage capacity in the roots (Figure B).…”

“…The net photosynthesis rate ( P n ) was measured with the portable photosynthesis system (LI-6400; Li-COR, Lincoln, NE, USA), maintaining the CO 2 concentration at 380 μmol mol –1 and photosynthetic photon flux density at 1000 μmol m –2 s –1 . The fourth fully expanded leaves from the bottom were used to measure the value of electrolyte leakage (EL) after 15 days of Cd treatment …”

“…The xylem sap exuding from the horizontal cut stem surface of 12 replicate detopped seedlings was collected and pooled and then diluted with deionized water for corresponding measurements …”

“…The reaction mix was incubated in the dark in a water bath for 30 min at 45 °C, and the reaction was terminated by the addition of 100 μL of 1.0 mol of methanesulfonic acid at −20 °C for up 7 days prior to high-performance liquid chromatography (HPLC) analysis to detect the in vivo thiol and PC concentrations using an HPLC 1200 series system with a reverse-phase column. The excitation and emission wavelengths were set to 380 and 470 nm, respectively, as described by Zhong et al The NPT standards, including gamma-glutamyl-cysteine, cysteine, glutathione (GSH), PC 2 , PC 3 , and PC 4 , were obtained as commercially available peptides from Sigma-Aldrich (St. Louis, MO, USA).…”