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Cadmium is not only seriously harmful to the growth and development of plants but threatens human health through the food chain. E3 ubiquitin ligase genes have been studied widely; however, whether it mediates cadmium stress in plants remains unclear. In this report, we provided evidence on the response of a U-box E3 ubiquitin ligase gene SlUPS to cadmium stress. The full-length CDS of SlUPS was 873 bp, with 223 amino acid residues. SlUPS was sufficiently induced by cadmium in leaf and root tissues. The expression of the SlUPS gene reached the maximum in leaves and roots in 3 and 9 h during CdCl2 treatment. The gene expression increased with progressively increasing concentrations of cadmium. The viability of yeast carrying pYES2-SlUPS, with SlUPS overexpressed, was higher than that in the control group. The transgenic Arabidopsis plants that overexpressed SlUPS showed a significantly higher germination rate and better growth than the control plants during the cadmium treatment. In summary, our study showed that SlUPS might positively regulate the plant response to cadmium stress. These results provided insights facilitating further investigations into the roles of U-box E3 ubiquitin ligase genes in heavy metal stress. [ABSTRACT FROM AUTHOR]

Previous studies identified that strigolactones (SLs) and gibberellins (GAs) interacted when controlling branching in plant shoots, but the underlying mechanism remains unknown. qRT-PCR analysis suggested that the SL receptor gene CsDAD2 was significantly upregulated in the leaves, stems, and nodes of cucumber after treatment with 50 mg/L of GA3. Furthermore, the CsDAD2 gene was cloned and introduced into wild-type Arabidopsis plants via Agrobacterium-mediated transformation. For the CsDAD2-OE lines, the endogenous content of GA3 was subsequently higher at the seedling stage, with the number of primary cauline branches also significantly increased at the maturity stage compared with WT. Additionally, GA-related genes were up-regulated in the first inter-nodes and the third nodes of the CsDAD2-OE lines, thus indicating that GA was metabolically active in these tissues. The expression of the branch inhibitor gene AtBRC1 decreased at the seedling stage as well as at the maturity stage of the CsDAD2-OE lines. These findings suggest that CsDAD2 might have important functions in the interactions between GAs and SLs as it can promote the accumulation of GAs in plant nodes and suppress the expression of BRC1, hence increasing primary cauline branching. [ABSTRACT FROM AUTHOR]

In order to facilitate self-compacting concrete to be better used in tunnel linings that can resist fires, a SiO2 aerogel-cement mortar coating was prepared. Based on the HC curve, a self compacting concrete cube specimens coated and uncoated with SiO2 aerogel-cement mortar (SiO2-ACM) were heated to simulate tunnel fire for 0.5, 1, 1.5, 2, 2.5, 3 and 4 h, respectively.The residual compressive strength was tested after the specimens were cooled to room temperature by natural cooling and water cooling. The results show that, the damages of specimens become more serious as fire time goes on, but the residual strength of specimens coated with SiO2-ACM is always higher than that of uncoated with SiO2-ACM. In addition, the residual strength of specimens cooled by water cooling is lower than that of natural cooling. However, for the specimens coated with SiO2-ACM, the adverse effects of water cooling are lessened. With the increase of fire time, the protective effect of SiO2-ACM is still gradually improved. Finally, a formula was established to predict the residual 150 mm cube compressive strength of specimens protected by SiO2-ACM after a simulated tunnel fire. [ABSTRACT FROM AUTHOR]

Different C influences the kinetic and thermodynamic behavior of catalase (CAT) remains unknown. The study aimed to assess the impact of three different C [straw, biochar, nanocarbon] on kinetic and thermodynamic characteristic of CAT in 5 °C ~ 45 °C. These three C-sources increased Vmax, Vmax/Km, and decreased Km, ΔG, ΔH, ΔS at different temperatures. The addition of nanocarbon induced significant changes in the soil enzymatic characteristics, resulting in the highest soil CAT-activity. After continuous-heating, the addition of three C-sources to the soil increased and then decreased the CAT-activity and its kinetic parameters and their values peaked at 15 °C or 25 °C. On the other hand, the ΔG showed decreasing and then increasing trend and ΔS gradually increased. Q 10 decreased and correlations between CAT and kinetic thermodynamic parameters were observed with increasing-temperature in three C-treatments. There was a significant correlation between soil’s physicochemical properties and soil CAT-activity and their enzymatic reaction characteristics after straw and biochar-treatments. However, an insignificant correlation was observed between the soil indexes after the nanocarbon-treatment. Thus, different C-sources could increase the soil CAT-activity by promoting the enzymatic reaction process under continuous-warming. The continues-warming without any change in the temperature-adaptation of CAT, but its temperature-sensitivity decreased after C-source addition. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), as a heavy metal, not only negatively affects the development and yield of plants, but also threatens human health due to its accumulation in plants. Increasing evidences indicate that the JUMONJI-C DOMAIN-CONTAINING PROTEIN (JMJ) gene family plays a key role in regulating plant development and stress. Therefore, in this study, SlJMJ524 , a 1254 bp gene encoding the jumonji C domain (417 amino acids), was highly expressed in tomato leaves and flowers. Interestingly, the transgenic plants exhibited sensitivity to Cd during post-germination stage but showed enhanced tolerance to the heavy metal during adult stage. Overexpression of SlJMJ524 increased the expression level of related proteins gene involved in heavy metal uptake while increasing Cd tolerance through the GSH-PC pathway. The higher transcription of genes related to flavonoid synthesis reflected higher accumulations of flavonoids in transgenic plants. Our study demonstrated that the ectopic expression of SlJMJ524 conferred the transgenic plants many traits for improving cadmium stress tolerance at different developmental stages. This study advances our collective understanding of the functional role of JMJs and can be used to improve the cadmium tolerance and breeding of crops and plants. [Display omitted] • Transgenic Arabidopsis was sensitive to Cd during germination stages, showing tolerance during seedling and mature stages. • SlJMJ524 might affect plants cadmium tolerance by regulating the expression of metal transporter related genes. • SlJMJ524 might resist cadmium-induced stress by increasing the flavonoid content of the plant. [ABSTRACT FROM AUTHOR]