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Carotenoid biosynthetic pathway produces not only pigments that protect photosynthetic system against photo-oxidative damage, but also precursors of abscisic acid, the major hormone regulates stress responses. To understand the response of carotenoid biosynthetic pathway to salt stress, the expression of the genes involved in carotenoid and ABA biosynthesis were compared in cultivated tomato Solanum lycopersicon cv. Moneymaker and its relative wild genotype S. pimpinellifolium (PI365967) together with the contents of carotenoids and ABA. The results showed that 11 of the 15 genes investigated were up-regulated and four unaltered in Moneymaker after 5 h of salt stress; whereas only four genes were up-regulated, four unaltered, and seven down-regulated in PI365967 after stress. Further comparison revealed that 11 salinity-induced genes were expressed significantly lower in Moneymaker than in PI365967 under normal condition, and 8 of them were induced to similar levels after salt stress. In consistence, ABA level was doubled in Moneymaker but kept consistent in PI365967 after salt stress, though the contents of neoxanthin, violaxanthin, β-carotene, lutein, and total carotenoids were kept unchanged in both species. Since it is known that PI365967 is more tolerant to salt stress than Moneymaker, we proposed that the constitutive high level of carotenoid and ABA biosynthetic pathway under normal growth condition could be benefit to PI365967 for establishing the early response to salt stress. In addition, CrtR-b1 and CrtR-b2 that encode β-carotenoid hydroxylases were the only genes in carotenoid biosynthetic pathway that were up-regulated by salt stress in both species. The CrtR-b2 gene was cloned from both species and no essential difference was found in the encoded amino acid sequences. Transformation of CrtR-b2 to tobacco improved the seed germination under salt stress condition, indicating that the hydrolysis of β-carotenoid is the target of transcriptional regulation of the carotenoid biosynthesis in both tomato cultivar and wild relative.

Camellia is the largest and most important genus in the family Theaceae, with many species being of great economic, ornamental and ecological value. However, the phylogenetic resolution of these species has been difficult due to interspecific hybridization and polyploidy. Consequently, the interspecies relationships of the genus Camellia are still hotly debated. In this study, four chloroplast genomic regions (matK, rbcL, ycf1, trnL-F) were used as markers among 161 species representing all four subgenera within this genus to investigate the phylogeny and interspecies relationship of the genus Camellia. The results showed that the 161 species of the genus Camellia could be grouped into 13 clades (A-M). Clades A and B mainly consisted of sect. Camellia. Clades C and I were made up of sect. Theopsis and sect. Eriandria. Clades D and J were composed of species from sect. Thea. Clade F consisted of the sect. Paracamellia species, whilst Clades G and M included sect. Furfuracea species. Clade H contained sect. Tuberculata and most species of sect. Pseudocamellia, whereas Clades K and L comprised the sect. Chrysantha species. These results supported that 161 Camellia species form paraphyletic groups, rather than a monophyletic group. And they demonstrated that the taxonomic position of related species could be resolved to some extent via sequencing markers in organelle genome, thus providing valuable cytoplasmic genetic information or maternal genetic information for accurately identifying species, clarifying taxonomy and reconstructing the phylogeny of various Camellia species. [ABSTRACT FROM AUTHOR]

Theabrownins (TBs) are the characteristic functional and quality components of dark teas such as Pu'er tea and Chin-brick tea. TBs are a class of water-soluble brown polymers with multi-molecular weight distribution produced by the oxidative polymerisation of tea polyphenols during the fermentation process of dark tea, both enzymatically and non-enzymatically. TBs have been extracted and purified from dark tea all the time, but the obtained TBs contain heterogeneous components such as polysaccharides and caffeine in the bound state, which are difficult to remove. The isolation and purification process was tedious and required the use of organic solvents, which made it difficult to industrialise TBs. In this study, epigallocatechin (EGC), epigallocatechin gallate (EGCG), epigallocatechin gallate (ECG), EGC/EGCG (mass ratio 1:1), EGCG/ECG (mass ratio 1:1), EGC/ECG (mass ratio 1:1) and EGC/EGCG/ECG (mass ratio 1:1:1) as substrates and catalyzed by polyphenol oxidase (PPO) and peroxidase (POD) in turn to produce TBs, named TBs-dE-1, TBs-dE-2, TBs-dE-3, TBs-dE-4, TBs-dE-5, TBs-dE-6 and TBs-dE-7. The physicochemical properties and the antibacterial activity and mechanism of TBs-dE-1–7 were investigated. Sensory and colour difference measurements showed that all seven tea browning samples showed varying degrees of brownish hue. Zeta potential in aqueous solutions at pH 3.0–9.0 indicated that TBs-dE-1–7 was negatively charged and the potential increased with increasing pH. The characteristic absorption peaks of TBs-dE-1–7 were observed at 208 and 274 nm by UV-visible (UV-vis) scanning spectroscopy. Fourier transform infrared (FT-IR) spectra indicated that they were phenolic compounds. TBs-dE-1–7 showed significant inhibition of Escherichia coli DH5α (E. coli DH5α). TBs-dE-3 showed the strongest inhibitory effect with minimum inhibitory concentration (MIC) of 1.25 mg mL–1 and MBC of 10 mg mL–1, followed by TBs-dE-5 and TBs-dE-6. These three TBs-dEs were selected to further investigate their inhibition mechanism. The TBs-dE was found to damage the extracellular membrane of E. coli DH5α, causing leakage of contents, and increase intracellular reactive oxygen content, resulting in abnormal cell metabolism due to oxidative stress. The results of the study provide a theoretical basis for the industrial preparation and product development of TBs.

Background and aims: Idiopathic pulmonary fibrosis (IPF) is a fibrosing lung disease with unknown etiology, leading to cough and dyspnoea, which is also one of the most common sequelae affecting the quality of life of COVID-19 survivors. There is no cure for IPF patients. We aim to develop a reliable IPF animal model with quantification of fibrosis based on Micro-Computer Tomography (micro-CT) images for the new drug discovery, because different bleomycin administration routes, doses, and intervals are reported in the literature, and there is no quantitative assessment of pulmonary fibrosis based on micro-CT images in animal studies. Methods: We compared three dosages (1.25 mg/kg, 2.5 mg/kg, and 5 mg/kg) of intratracheal bleomycin administration and experiment intervals (14 and 21 days) in C57BL/6 mice by investigating survival rates, pulmonary histopathology, micro-CT, peripheral CD4+ & CD8+ cells, and cytokines. Moreover, a simple and reliable new method was developed for scoring fibrosis in live mice based on Micro-CT images by using Image J software, which transfers the dark sections in pulmonary Micro-CT images to light colors on a black background. Results: The levels of hydroxyproline, inflammation cytokine, fibrotic pathological changes, and collagen deposition in the lungs of mice were bleomycin dose-dependent and time-dependent as well as the body weight loss. Based on the above results, the mice model at 21 days after being given bleomycin at 1.25 mg/kg has optimal pulmonary fibrosis with a high survival rate and low toxicity. There is a significant decrease in the light area (gray value at 9.86 ± 0.72) in the BLM mice, indicating that a significant decrease in the alveolar air area was observed in BLM injured mice compared to normal groups (###p < 0.001), while the Pirfenidone administration increased the light area (gray value) to 21.71 ± 2.95 which is close to the value observed in the normal mice (gray value at 23.23 ± 1.66), which is consistent with the protein levels of Col1A1, and α-SMA. Notably, the standard deviations for the consecutive six images of each group indicate the precision of this developed quantitation method for the micro-CT image taken at the fifth rib of each mouse. Conclusion: Provided a quantifying method for Micro-CT images in an optimal and repeatable pulmonary fibrosis mice model for exploring novel therapeutic interventions.

To cope with environmental stresses, plants often adopt a memory response upon primary stress exposure to facilitate a quicker and stronger reaction to recurring stresses. However, it remains unknown whether light is involved in the manifestation of stress memory. Proline accumulation is a striking metabolic adaptation of higher plants during various environmental stresses. Here we show that salinity-induced proline accumulation is memorable and HY5-dependent light signaling is required for such a memory response. Primary salt stress induced the expression of Δ¹-pyrroline-5-carboxylate synthetase 1 (P5CS1), encoding a proline biosynthetic enzyme and proline accumulation, which were reduced to basal level during the recovery stage. Reoccurring salt stress-induced stronger P5CS1 expression and proline accumulation were dependent upon light exposure during the recovery stage. Further studies demonstrated that salt-induced transcriptional memory of P5CS1 is associated with the retention of increased H3K4me3 level at P5CS1 during the recovery stage. HY5 binds directly to light-responsive element, C/A-box, in the P5CS1 promoter. Deletion of the C/A-box or hy5 hyh mutations caused rapid reduction of H3K4me3 level at P5CS1 during the recovery stage, resulting in impairment of the stress memory response. These results unveil a previously unrecognized mechanism whereby light regulates salt-induced transcriptional memory via the function of HY5 in maintaining H3K4me3 level at the memory gene. [ABSTRACT FROM AUTHOR]

There are a number of challenging technical issues in mining the first seam with a high cutting single pass longwall method in thick and multiple gassy seams of short intervals in the western region of China. These issues include the stability of retained gateroads and the quantification of the extent and degree of destressed zones in surrounding strata. To gain an insight of these issues, a theoretical and numerical .study was undertaken for a 4.2 m cutting height face to understand the propagation and evolution of fractures around the face, to characterize the fracture distribution, and to map out the zones of high gas concentrations in the goaf. Based on these findings, a group of large diameter (φ = 250 mm) boreholes drilled into the zones,instead of conventionally expensive gas drainage tunnels, are successfully used to capture the goal gas. A total of 11. 669 5 million cubic meters gas is captured with the boreholes, a total of 677 000 tons of coal is efficiently extracted without any gas issue, and integrated coal and gas extraction is achieved. [ABSTRACT FROM AUTHOR]

The effect of proline (Pro) accumulation on heat sensitivity was investigated using transgenic Arabidopsis (Arabidopsis thaliana) plants ectopically expressing the A(1)-pyrroline-5-carboxylate synthetase 1 gene (AtP5CS1) under the control of a heat shock protein 17.6II gene promoter. During heat stress, the heat-inducible expression of the AtP5CS1 transgene was capable of enhancing Pro biosynthesis. Twelve-day-old seedlings were first treated with heat at 37°C for 24 h to induce Pro and then were stressed at 50°C for 4 h. After recovery at 22°C for 96 h, the growth of Pro-overproducing plants was significantly more inhibited than that of control plants that do not accumulate Pro, manifested by lower survival rate, higher ion leakage, higher reactive oxygen species (ROS) and malondialdehyde levels, and increased activity of the Pro/P5C cycle. The activities of anti-oxidant enzymes superoxide dismutase, guaiacol peroxidase, and catalase, but not those of glutathione reductase and ascorbate peroxidase, increased in all lines after heat treatment, but the increase was more significant in Pro-overproducing seedlings. Staining with MitoSox-Red, reported for being able to specifically detect superoxide formed in mitochondria, showed that Pro accumulation during heat stress resulted in elevated levels of ROS in mitochondria. Interestingly, exogenous abscisic acid (ABA) and ethylene were found to partially rescue the heat-sensitive phenotype of Pro-overproducing seedlings. Measurement of ethylene and ABA levels further confirmed that these two hormones are negatively affected in Pro-overproducing seedlings during heat stress. Our results indicated that Pro accumulation under heat stress decreases the thermotolerance, probably by increased ROS production via the Pro/PSC cycle and inhibition of ABA and ethylene biosynthesis. [ABSTRACT FROM AUTHOR]

The "capacity of deep rock breakage mechanics and supporting technique model test" was used to research the mechanism of zone disintegration within surrounding rock of mine in deep stratum, and the failure state and principle of the uprightwall-crown section mine bearing maximum load that paralleling the mine axis line was systematically studied. The model test results show that the major radial tension strain following tension breakage in country rock is the key factor of generation of zonal disintegration around mine when the country rock is in dilatancy state, and the distribution characteristic of radial tension strain is that the stain value is increasing with the axial load raising and is decreasing with the distance from mine wall increasing. A new equivalent radius enlarged mine is emerged after the tension breakage face is formed, and in the persistence major axial load state, the broken zone and unbroken zone that is zone disintegration can be generated in country mine rock with the tension breakage appearing interactively. [ABSTRACT FROM AUTHOR]

The effect of proline (Pro) accumulation on heat sensitivity was investigated using transgenic Arabidopsis (Arabidopsis thaliana) plants ectopically expressing the A(1)-pyrroline-5-carboxylate synthetase 1 gene (AtP5CS1) under the control of a heat shock protein 17.6II gene promoter. During heat stress, the heat-inducible expression of the AtP5CS1 transgene was capable of enhancing Pro biosynthesis. Twelve-day-old seedlings were first treated with heat at 37°C for 24 h to induce Pro and then were stressed at 50°C for 4 h. After recovery at 22°C for 96 h, the growth of Pro-overproducing plants was significantly more inhibited than that of control plants that do not accumulate Pro, manifested by lower survival rate, higher ion leakage, higher reactive oxygen species (ROS) and malondialdehyde levels, and increased activity of the Pro/P5C cycle. The activities of anti-oxidant enzymes superoxide dismutase, guaiacol peroxidase, and catalase, but not those of glutathione reductase and ascorbate peroxidase, increased in all lines after heat treatment, but the increase was more significant in Pro-overproducing seedlings. Staining with MitoSox-Red, reported for being able to specifically detect superoxide formed in mitochondria, showed that Pro accumulation during heat stress resulted in elevated levels of ROS in mitochondria. Interestingly, exogenous abscisic acid (ABA) and ethylene were found to partially rescue the heat-sensitive phenotype of Pro-overproducing seedlings. Measurement of ethylene and ABA levels further confirmed that these two hormones are negatively affected in Pro-overproducing seedlings during heat stress. Our results indicated that Pro accumulation under heat stress decreases the thermotolerance, probably by increased ROS production via the Pro/PSC cycle and inhibition of ABA and ethylene biosynthesis. [ABSTRACT FROM AUTHOR]