S-nitrosoglutathione reductase (GSNOR) exerts crucial roles in the homeostasis of nitric oxide (NO) and reactive nitrogen species (RNS) in plant cells through indirect control of S-nitrosation, an important protein post-translational modification in signaling pathways of NO. Using cultivated and wild tomato species, we studied GSNOR function in interactions of key enzymes of reactive oxygen species (ROS) metabolism with RNS mediated by protein S-nitrosation during tomato root growth and responses to salinity and cadmium. Application of a GSNOR inhibitor N6022 increased both NO and S-nitrosothiol levels and stimulated root growth in both genotypes. Moreover, N6022 treatment, as well as S-nitrosoglutathione (GSNO) application, caused intensive S-nitrosation of important enzymes of ROS metabolism, NADPH oxidase (NADPHox) and ascorbate peroxidase (APX). Under abiotic stress, activities of APX and NADPHox were modulated by S-nitrosation. Increased production of H2O2 and subsequent oxidative stress were observed in wild Solanumhabrochaites, together with increased GSNOR activity and reduced S-nitrosothiols. An opposite effect occurred in cultivated S. lycopersicum, where reduced GSNOR activity and intensive S-nitrosation resulted in reduced ROS levels by abiotic stress. These data suggest stress-triggered disruption of ROS homeostasis, mediated by modulation of RNS and S-nitrosation of NADPHox and APX, underlies tomato root growth inhibition by salinity and cadmium stress.

• MeSH
• aldehydoxidoreduktasy metabolismus   MeSH
• askorbátperoxidasa metabolismus   MeSH
• benzamidy chemie   metabolismus   farmakologie   MeSH
• chlorid sodný farmakologie   MeSH
• fyziologický stres MeSH
• kadmium toxicita   MeSH
• kořeny rostlin účinky léků   růst a vývoj   metabolismus   MeSH
• NADPH-oxidasy metabolismus   MeSH
• nitrosace MeSH
• oxid dusnatý metabolismus   MeSH
• oxidační stres účinky léků   MeSH
• peroxid vodíku metabolismus   MeSH
• pyrroly chemie   metabolismus   farmakologie   MeSH
• reaktivní formy dusíku chemie   metabolismus   MeSH
• reaktivní formy kyslíku chemie   metabolismus   MeSH
• regulace genové exprese u rostlin účinky léků   MeSH
• rostlinné proteiny metabolismus   MeSH
• S-nitrosoglutathion farmakologie   MeSH
• S-nitrosothioly metabolismus   MeSH
• Solanum lycopersicum účinky léků   růst a vývoj   metabolismus   MeSH
• Solanum růst a vývoj   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Polybrominated diphenyl ethers (PBDEs) are used as additive flame retardants. PBDEs are persistent, bioaccumulative and toxic compounds. They are often detected in sewage sludge which is applied on agricultural soils as fertilizer. The objective of this study was to find out whether plants are able to accumulate and translocate PBDEs. Tobacco (Nicotiana tabacum) and nightshade (Solanum nigrum) were planted in pots containing contaminated sewage sludge and uncontaminated substrate. After 6 months of plant cultivation in sewage sludge up to 15.4 ng g(-1) dw and 76.6 ng g(-1) dw of PBDE congeners--BDE 47, BDE 99 and BDE 100---were accumulated in the nightshade and tobacco tissue, respectively. Corresponding values in plants vegetated in the control garden substrate were 10 times lower. The bioconcentration factors (BCFs) of accumulated congeners were calculated. Tobacco exhibited higher BCFs values and for both plants BCFs values of BDE 47, BDE 99, BDE 100 and BDE 209 negatively correlated with their octanol-water partition coefficients (logK(ow)). The exception was decaBDE (BDE 209) which was accumulated only in tobacco tissue in the concentration of 116.8 ng g(-1) dw. The majority of PBDEs was detected in above-ground plant biomass indicating that both plants have the ability to translocate PBDEs. To our knowledge this is one of the first studies reporting the accumulation of both lower PBDEs and BDE 209 in plants. Our results suggest that absorption, accumulation and translocation of PBDEs by plants and their transfer to the food chain could represent another possible risk for human exposure.

• MeSH
• biodegradace MeSH
• halogenované difenylethery analýza   metabolismus   MeSH
• látky znečišťující půdu analýza   metabolismus   MeSH
• odpadní vody chemie   MeSH
• retardanty hoření analýza   metabolismus   MeSH
• rostliny metabolismus   MeSH
• Solanum růst a vývoj   metabolismus   MeSH
• tabák růst a vývoj   metabolismus   MeSH
• vývoj rostlin MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH