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Most of the upregulated genes contributed to the accumulation of soluble sugars and ABA in the phloem of 'Vitis amurensis' compared to 'Merlot' during cold acclimation. Extreme cold is one of the dominant abiotic factors affecting grape yield and quality. However, the changes in sugars, phytohormones, and gene expression in the branch phloem of different tolerant grape varieties during cold acclimation remain elusive. The data supported that with decreasing temperature, the contents of fructose, sucrose, and ABA in the phloem of Vitis amurensis (cold-tolerant, T) and 'Merlot' (cold-sensitive, S) increased during cold acclimation, and these indicators were higher in T than in S. Furthermore, the activities of sucrose synthetase, sucrose phosphate synthetase, and acid invertase peaked in the early phase of cold acclimation (approximately 5 °C) compared to other phases (approximately 28 °C, 0 °C, - 5 °C and - 10 °C). Moreover, the RNA sequencing results helped identify a total of 11,343 differentially expressed genes in the phloem of T and S, among which 4912 were upregulated and 6431 were downregulated. In the abscisic acid pathway, CRTISO, PSPY1-1, CYCP707A4-2, PYL4-1, PYL4-2, P2C08, SAPK2, TARAB1, and DBF3 were more highly expressed in T than in S. In the starch and sucrose metabolism pathway, HXK1, PGMP, GLGL1, SUS6, VCINV, BGL11, SSY1, GPS, BAM1 and BAM3 were also more highly expressed in T than in S. Moreover, the genes related to oxidative phosphorylation, such as NDHF, ND4, ND1, NAD7, NAD2, ATPB, YMF19, ATP9, PMA1 and AHA8, were upregulated in T. These results will be beneficial for understanding the potential differences in tolerance across two different cold-tolerant grapes with respect to sugar metabolism and gene expression.

Alcohol has been demonstrated to disrupt intestinal barrier integrity. Some flavonoid compounds that exert antioxidant activity have a protective effect on intestinal barrier function. As an important medicinal and edible plant, sea buckthorn (Hippophae) seeds are rich in flavonoids, but their protective effect on the intestinal barrier has not been reported. In our research, 76 kinds of flavonoids were identified in Hippophae rhamnoides ssp. sinensis seed residue flavonoids (HRSF) by ultra-performance liquid chromatography–tandem mass spectrometry. Kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, kaempferol-3-O-robinoside-7-O-rhamnoside, isorhamnetin-3-O-2G-rhamnosylrutinoside, quercetin-3-O-rutinoside, (−)-epigallocatechin, and B type of procyanidin were the most abundant substances, accounting for 15.276%, 15.128%, 18.328%, 10.904%, 4.596%, 5.082%, and 10.079% of all identified flavonoids, respectively. Meanwhile, pre-treatment with HRSF was able to prevent alcohol-induced disruption of intestinal barrier integrity through elevating the transepithelial monolayer resistance value, inhibiting the flux of fluorescein isothiocyanate-dextran, and upregulating the mRNA and protein level of TJs (occludin and ZO-1). Furthermore, it was also able to reverse alcohol-induced oxidative stress through suppressing the accumulation of reactive oxygen species and malondialdehyde, improving the glutathione level and superoxide dismutase activity. Finally, the results showed that HRSF pre-treatment effectively elevated the erythroid-related factor 2 mRNA and protein level compared with the alcohol-alone treatment group. Our research was the first to demonstrate that HRSF could prevent alcohol-induced intestinal barrier dysfunction through regulating the Nrf2-mediated pathway in order to attenuate oxidative stress and enhance TJ expression.

Fusarium solani is the most significant pathogen that causes root rot in wolfberry, which has led to serious economic losses in terms of production. As an important enzyme in organisms, NADPH oxidase produces ROS. However, the mechanism of ROS mediated by NADPH oxidase in the growth of F. solani has not been studied. In this study, F. solani colonies were treated with 40 µmol/L DPI and 0.0012% H2O2. The growth rate in terms of colonies, number of spores, key gene expression levels, activity of key enzymes and the content of key products of ROS metabolic pathways were determined. The results showed that the growth rate of colonies treated by DPI decreased by 19.43%, the number of macroconidia increased by 231.03%, the IOD/area values of O2− and H2O2 decreased by 34.88% and 16.97%, respectively, the expression levels in terms of NCF2, SOD1, CTA1 and PXMP4 significantly decreased and the activities of SOD, CAT and POD decreased significantly, while the MDA content increased significantly. Additionally, in the case of the colonies treated with exogenous H2O2, the MDA content decreased significantly while the other indicators increased. Taken together, the NCF2 gene is involved in regulating the activity of NADPH oxidase and regulates the products of O2− and ROS metabolism enzyme genes and their activities to affect colony growth in the F. solani growth process.

Background Low temperature (LT) is one of the main limiting factors that affect growth and development in grape. Increasing soluble sugar and scavenging reactive oxygen species (ROS) play critical roles in grapevine resistance to cold stress. However, the mechanism of β-amylase (BAM) involved in the regulation of sugar levels and antioxidant enzyme activities in response to cold stress is unclear. Results In this study, six BAM genes were identified and clustered into four groups. Multiple sequence alignment and gene structure analysis showed that VvBAM6 lacked the Glu380 residue and contained only an exon. The transcript abundance of VvBAM1 and VvBAM3 significantly increased as temperature decreased. After LT stress, VvBAM1 was highly expressed in the leaves, petioles, stems, and roots of overexpressing tomato lines. The total amylase and BAM activities increased by 6.5- and 6.01-fold in transgenic plants compared with those in wild-type tomato plants (WT) subjected to LT, respectively. The glucose and sucrose contents in transgenic plants were significantly higher than those in WT plants, whereas the starch contents in the former decreased by 1.5-fold compared with those in the latter under LT stress. The analysis of transcriptome sequencing data revealed that 541 genes were upregulated, and 663 genes were downregulated in transgenic plants. One sugar transporter protein gene (SlSTP10), two peroxidase (POD)-related genes (SlPER7 and SlPER5), and one catalase (CAT)-related gene (SlCAT1) were upregulated by 8.6-, 3.6-, 3.0-, and 2.3-fold in transgenic plants after LT stress, respectively. Conclusions Our results suggest that VvBAM1 overexpression promotes ROS scavenging and improves cold tolerance ability by modulating starch hydrolysis to affect soluble sugar levels in tomato plants.

Additional file 2: Supplementary Table S2. Information of the BAM genes used to construct the phylogenetic tree in Fig. 1a.

Additional file 1: Supplementary Table S1. qRT-PCR primers for expression on analysis of VvBAM genes.

Additional file 3: Supplementary Table S3. Summary of reads based on RNA sequence data obtained from each sample after 24 h LT stress.

Additional file 4: Supplementary Table S4. Annotation information of DEGs in heatmaps.

Comparative Study of Effects of Thio/Oxo Ester Linkages on Thermal Properties of Bacterial Poly[3-hydroxybutyrate- co -3-(mercapto/hydroxy)propionate]s

The enzymatic hydrolysis behavior of compositionally well-fractionated bacterial poly(3-hydroxybutyrate- co -3-hydroxyvalerate) [P(3HB- co -3HV)] with 3HV-unit content from 8 to 98 mol% and bacterial poly(3-hydroxybutyrate) [P(3HB)] has been investigated in the presence of poly(3-hydroxyalkanoate) depolymerases isolated from Ralstonia pickettii T1 and Acidovorax sp. TP4. The water-soluble degradation products were characterized by HPLC and 1 H NMR spectroscopy. P(3HB- co -3HV)s with the whole range of 3HV-unit content can be degraded by R. pickettii T1 depolymerase, while only P(3HB- co -3HV)s with 3HV-unit content less than 80 mol% can be degraded by Acidovorax sp. TP4 depolymerase. It was found that the enzymatic degradation behavior of fractionated P(3HB- co -3HV)s was affected not only by the comonomer unit composition and its distribution but also by the solid-state structure of P(3HB- co -3HV)s and further by the bacterial source of depolymerases. Based on the results, the mechanism of enzymatic degradation was discussed.

Lidan Feng, Takumi Watanabe, Yong He, Yi Wang, Tomoyasu Kichise, Takeshi Fukuchi, Guo-Qiang Chen, Yoshiharu Doi, Yoshio Inoue* 1 Department of Biomolecular Engineering, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama 226-8501, Japan Fax: (þ81)45-924-5827; E-mail: yinoue@bio.titech.ac.jp 2 Polymer Chemistry Laboratory, RIKEN Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan 3 Takasago Research Laboratories, Kaneka Corporation, Takasago, Hyogo 678-8688, Japan 4 Department of Biological Science & Biotechnology, Tsinghua University, Beijing 100084, China

This paper analyzes the existing problems on teaching resources database of colleges , expounds the features and advantages of cloud computing, besides, throw out some suggestion for college teaching resource database construction strategy and operation management mechanism based on cloud computing , provide new ideas for Construction of sharing platform of teaching resources in Colleges and Universities.

The comonomer-unit compositional distributions have been investigated for bacterial poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HH)] samples with 3HH unit content of 13.8, 18.0, 22.0, and 54.0 mol %. They were comonomer compositionally fractionated using chloroform/n-heptane mixed solvent at ambient temperature. The fractionation of P(3HB-co-18.0 mol %3HH) and P(3HB-co-22.0 mol % 3HH), which could not be carried out effectively at room temperature, were refractionated at 70 degrees C in the mixed solvent. Fractions with different 3HH unit content in a wide range (from 4.4 to 80.7 mol %) were obtained. By use of these fractions with narrow compositional distribution, the comonomer composition dependence of thermal properties was investigated by differential scanning calorimetry. The melting point (T(m)) and heat of fusion (DeltaH) decreased as the 3HH unit content increased in the range of low 3HH content (40 mol %), while they increased as the 3HH unit content increased in the high 3HH content range (70 mol %). The minimum T(m) and DeltaH values were found to exist at 3HH unit content of about 60 mol %. The glass transition temperature (T(g)) decreased linearly with the increase of 3HH unit content. The values of T(m), DeltaH, and T(g) of P(3HB-co-3HH)s were compared with those of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxypropionate), and poly(3-hydroxybutyrate-co-4-hydroxybutyrate), and the effects of comonomer types on the thermal properties were revealed.