Overexpression of Calcineurin B-like Interacting Protein Kinase 31 Promotes Lodging and Sheath Blight Resistance in Rice.

A breakthrough "Green Revolution" in rice enhanced lodging resistance by using gibberellin-deficient semi-dwarf varieties. However, the gibberellic acid (GA) signaling regulation on rice disease resistance remains unclear. The resistance test showed that a positive GA signaling regulator DWARF1 mutant d1 was more susceptible while a negative GA signaling regulator Slender rice 1 (SLR1) mutant was less susceptible to sheath blight (ShB), one of the major rice diseases, suggesting that GA signaling positively regulates ShB resistance. To isolate the regulator, which simultaneously regulates rice lodging and ShB resistance, SLR1 interactors were isolated. Yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BiFC), and Co-IP assay results indicate that SLR1 interacts with Calcineurin B-like-interacting protein kinase 31 (CIPK31). cipk31 mutants exhibited normal plant height, but CIPK31 OXs showed semi-dwarfism. In addition, the SLR1 level was much higher in CIPK31 OXs than in the wild-type, suggesting that CIPK31 OX might accumulate SLR1 to inhibit GA signaling and thus regulate its semi-dwarfism. Recently, we demonstrated that CIPK31 interacts and inhibits Catalase C (CatC) to accumulate ROS, which promotes rice disease resistance. Interestingly, CIPK31 interacts with Vascular Plant One Zinc Finger 2 (VOZ2) in the nucleus, and expression of CIPK31 accumulated VOZ2. Inoculation of Rhizoctonia solani AG1-IA revealed that the voz2 mutant was more susceptible to ShB. Thus, these data prove that CIPK31 promotes lodging and ShB resistance by regulating GA signaling and VOZ2 in rice. This study provides a valuable reference for rice ShB-resistant breeding.

Influence of High-Temperature and Intense Light on the Enzymatic Antioxidant System in Ginger (Zingiber officinale Roscoe) Plantlets.

Environmental stressors such as high temperature and intense light have been shown to have negative effects on plant growth and productivity. To survive in such conditions, plants activate several stress response mechanisms. The synergistic effect of high-temperature and intense light stress has a significant impact on ginger, leading to reduced ginger production. Nevertheless, how ginger responds to this type of stress is not yet fully understood. In this study, we examined the phenotypic changes, malonaldehyde (MDA) content, and the response of four vital enzymes (superoxide dismutase (SOD), catalase (CAT), lipoxygenase (LOX), and nitrate reductase (NR)) in ginger plants subjected to high-temperature and intense light stress. The findings of this study indicate that ginger is vulnerable to high temperature and intense light stress. This is evident from the noticeable curling, yellowing, and wilting of ginger leaves, as well as a decrease in chlorophyll index and an increase in MDA content. Our investigation confirms that ginger plants activate multiple stress response pathways, including the SOD and CAT antioxidant defenses, and adjust their response over time by switching to different pathways. Additionally, we observe that the expression levels of genes involved in different stress response pathways, such as SOD, CAT, LOX, and NR, are differently regulated under stress conditions. These findings offer avenues to explore the stress mechanisms of ginger in response to high temperature and intense light. They also provide interesting information for the choice of genetic material to use in breeding programs for obtaining ginger genotypes capable of withstanding high temperatures and intense light stress.

Starving the enemy: how plant and microbe compete for sugar on the border.

As the primary energy source for a plant host and microbe to sustain life, sugar is generally exported by Sugars Will Eventually be Exported Transporters (SWEETs) to the host extracellular spaces or the apoplast. There, the host and microbes compete for hexose, sucrose, and other important nutrients. The host and microbial monosaccharide transporters (MSTs) and sucrose transporters (SUTs) play a key role in the "evolutionary arms race". The result of this competition hinges on the proportion of sugar distribution between the host and microbes. In some plants (such as Arabidopsis, corn, and rice) and their interacting pathogens, the key transporters responsible for sugar competition have been identified. However, the regulatory mechanisms of sugar transporters, especially in the microbes require further investigation. Here, the key transporters that are responsible for the sugar competition in the host and pathogen have been identified and the regulatory mechanisms of the sugar transport have been briefly analyzed. These data are of great significance to the increase of the sugar distribution in plants for improvement in the yield.

Exogenous Melatonin Regulates Physiological Responses and Active Ingredient Levels in Polygonum cuspidatum under Drought Stress.

Polygonum cuspidatum, an important medicinal plant, is rich in resveratrol and polydatin, but it frequently suffers from drought stress in the nursery stage, which inhibits the plant's growth, active components concentrations, and the price of rhizome in the later stage. The purpose of this study was to analyze how exogenous 100 mM melatonin (MT) (an indole heterocyclic compound) affected biomass production, water potential, gas exchange, antioxidant enzyme activities, active components levels, and resveratrol synthase (RS) gene expression of P. cuspidatum seedlings growing under well-watered and drought stress conditions. The 12-week drought treatment negatively affected the shoot and root biomass, leaf water potential, and leaf gas exchange parameters (photosynthetic rate, stomatal conductance, and transpiration rate), whereas the application of exogenous MT significantly increased these variables of stressed and non-stressed seedlings, accompanied by higher increases in the biomass, photosynthetic rate, and stomatal conductance under drought versus well-watered conditions. Drought treatment raised the activities of superoxide dismutase, peroxidase, and catalase in the leaves, while the MT application increased the activities of the three antioxidant enzymes regardless of soil moistures. Drought treatment reduced root chrysophanol, emodin, physcion, and resveratrol levels, while it dramatically promoted root polydatin levels. At the same time, the application of exogenous MT significantly increased the levels of the five active components, regardless of soil moistures, with the exception of no change in the emodin under well-watered conditions. The MT treatment also up-regulated the relative expression of PcRS under both soil moistures, along with a significantly positive correlation between the relative expression of PcRS and resveratrol levels. In conclusion, exogenous MT can be employed as a biostimulant to enhance plant growth, leaf gas exchange, antioxidant enzyme activities, and active components of P. cuspidatum under drought stress conditions, which provides a reference for drought-resistant cultivation of P. cuspidatum.

Evaluation Soybean Cultivars for Reaction to Heterodera glycines Populations HG Types 7 and 1.3.4.7 in Northeast China.

Soybean cyst nematode Heterodera glycines (SCN) is a major threat to global soybean production. Effective management of this disease is dependent on the development of resistant cultivars. Two SCN HG Types, 7 and 1.3.4.7. were previously identified as prevalent H. glycines populations in Northeast China. In order to evaluate soybean cultivars resistant to local SCN populations, 110 domestic commercial soybeans from different regions of Northeast China were assessed in the greenhouse to determine their potential as novel sources of resistance. The results suggested that cultivars responded differently to the two HG types. Of the 110 soybean cultivars evaluated, 24 accessions were classified as resistant or moderately resistant to HG Type 7, and five cultivars were classified as resistant or moderately resistant to HG Type 1.3.4.7. Among the tested cultivars, Kangxian 12 and Qingdou 13 had resistance response to both HG types 7 and 1.3.4.7. Thus, these broad-based SCN cultivars will be the valuable materials in the SCN resistance breeding program.

Bioaffinity ultrafiltration coupled with HPLC-ESI-MS/MS for screening potential α-glucosidase inhibitors from pomegranate peel.

Pomegranate peel (PoP) contains plenty of bioactive compounds and exhibits strong activity to prevent postprandial hyperglycaemia and improve diabetes mellitus. Presently, bioaffinity ultrafiltration coupled with high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS/MS) is employed to screen and identify the efficient α-glucosidase inhibitors in PoP and the detailed inhibitory mechanisms are further investigated. The results show that many substances, including ellagic acid, kaempferol, gallic acid, and resveratrol in PoP reveal strong activity to inhibit α-glucosidase and ellagic acid (EA) is screened as the most effective compound. Further research indicates that EA plays a competitive and reversible inhibition role against α-glucosidase with the value of Ki was 6.24 × 105 mol/L. EA also directly interacts with the amino acids of α-glucosidase mainly via van der Waals forces and hydrogen bonds, thereby, influencing the secondary structure and stability of α-glucosidase. Finally, the α-glucosidase inhibitory activity of EA is further confirmed to significantly reduce postprandial blood glucose in vivo.

Application Effect of External and Internal Elevation of Maxillary Sinus in Implant Restoration of Posterior Maxilla.

Objective: To explore and analyze the application effect of external and internal elevation of the maxillary sinus in implant restoration of the posterior maxilla. Methods: A total of 84 patients undergoing implant restoration of the posterior maxilla in the hospital were enrolled between January 2019 and March 2021. According to the random number table method, they were divided into the observation group (n = 42) and the control group (n = 42). The control group underwent external elevation of the maxillary sinus, while the observation group underwent internal elevation of the maxillary sinus. At 6 h, 12 h, and 24 h after surgery, the pain degree between the two groups was compared. All were followed up at 6 months after surgery. The osseointegration (bone resorption around implants, elevation height of maxillary sinus floor, average healing time) and soft tissues (bleeding index, plaque index, probing depth) in both groups were observed. The occurrence of postoperative complications was recorded. Results: At 6 h, 12 h, and 24 h after surgery, VAS scores in the observation group were significantly lower than those in the control group (P < 0.05). At 6 months after surgery, bone resorption and elevation height of the maxillary sinus floor in the observation group were significantly higher than those i.0.0n the control group, and the average healing time was significantly shorter than that in the control group (P < 0.05). The bleeding index, plaque index, and probing depth in the observation group were significantly lower than those in the control group (P < 0.05). There was no significant difference in the incidence of postoperative complications between the observation group and the control group (9.52% vs. 19.05%) (P > 0.05). Conclusion: The application effect of internal elevation of the maxillary sinus is good in implant restoration of the posterior maxilla, which can relieve pain and swelling and improve implant effect.

Fabrication, Properties, and Biomedical Applications of Calcium-Containing Cellulose-Based Composites.

Calcium-containing cellulose-based composites possess the advantages of high mechanical strength, excellent osteoconductivity, biocompatibility, biodegradation, and bioactivity, which represent a promising application system in the biomedical field. Calcium-containing cellulose-based composites have become the hotspot of study of various biomedical fields. In this mini-review article, the synthesis of calcium-containing cellulose-based composites is summarized via a variety of methods such as the biomimetic mineralization method, microwave method, co-precipitation method, hydrothermal method, freeze-drying method, mechanochemical reaction method, and ultrasound method. The development on the fabrication, properties, and applications of calcium-containing cellulose-based composites is highlighted. The as-existed problems and future developments of cellulose-based composites are provided. It is expected that calcium-containing cellulose-based composites are the ideal candidate for biomedical application.

Electrochemical Behavior and Direct Quantitative Determination of Paclitaxel.

The electrochemical behavior and direct quantitative determination of paclitaxel, a poorly soluble drug made into microemulsion, were researched by cyclic voltammetry in acetate buffer solutions (pH = 4.0) at a glassy carbon electrode. The results show that the oxidation process is irreversible and controlled by diffusion. Moreover, the effects of anodic peak current (Ipa), anodic peak potential, scan rate, pH, and the electrochemical redox mechanism have been studied. The anodic peak current varied linearly with paclitaxel concentration in the range of 5 × 10-5 mol/L to 5 × 10-4 mol/L, and the detection limit was 9.15 × 10-8 mol/L. The results of RSD (0.90%) and recovery (99.22%-101.69%) were obtained. Additionally, it has been proved that one electron and one proton are involved in the electrochemical redox process. The present research has been successfully used to determine paclitaxel in pure and real samples, which further supported the electrochemical behavior investigation of paclitaxel and direct determination of micro-emulsion.

Multifunctional Cellulose and Cellulose-Based (Nano) Composite Adsorbents.

In recent years, faced with the improvement of environmental quality problems, cellulose and cellulose-based (nano) composites have attracted great attention as adsorbents. In this review article, we first report the recent progress of modification and functionalization of cellulose adsorbents. In addition, the adsorbents produced by the modification and functionalization of carboxymehyl cellulose are also introduced. Moreover, the cellulose-based (nano) composites as adsorbents are reviewed in detail. Finally, the development prospect of cellulose and cellulose-based (nano) composites is studied in the field of the environment. In this review article, a critical comment is given based on our knowledge. It is believed that these biomass adsorbents will play an increasingly important role in the field of the environment.

Simultaneous detection of mercury (II), lead (II) and silver (I) based on fluorescently labelled aptamer probes and graphene oxide.

We have developed a fluorescence quantitative analysis method for the simultaneous detection of Hg2+, Pb2+ and Ag+ based on fluorescently labelled nucleic acid aptamer probes and graphene oxide (GO). By this method, three nucleic acid aptamer probes (PHg, PPb, PAg) were designed. The carboxyl fluorescein (FAM), tetramethyl-6-carboxyrhodamine (TAMRA) and cyanine-5 (Cy-5) were respectively selected as fluorophore of aptamer probes, and GO was chosen as quencher. In general, these probes were on free single-stranded state and adsorbed on the surface of GO via π-π interactions, which brought fluorophores of probes and GO into close proximity. Due to the fluorescence resonance energy transfer occurred between fluorophores and GO, the fluorescence was quenched and fluorescence signals were all weak. Under the optimal condition, fluorescence intensities of three fluorophores exhibited a good linear dependence on corresponding ions concentration. The detection limit for Hg2+, Pb2+ and Ag+ were 0.2, 0.5 and 2 nmol/L (3σ, n = 11). Average recoveries of this method were 97.56-104.92%, which indicated the method had a high accuracy and low detection limit. In addition, this proposed method has good selectivity, and there was no crosstalk effect among these probes.

Proanthocyanidin B2 attenuates postprandial blood glucose and its inhibitory effect on alpha-glucosidase: analysis by kinetics, fluorescence spectroscopy, atomic force microscopy and molecular docking.

As a dimer of proanthocyanidin, proanthocyanidin B2 (PB2) was found to effectively attenuate postprandial blood glucose in mice after sucrose loading. Further studies showed that PB2 revealed strong inhibitory activity against α-glucosidase with an IC50 value of (0.23 ± 0.01) µg mL-1, and this process was reversible with a mixed-type inhibitory manner. PB2 quenched the intrinsic fluorescence of α-glucosidase through a static quenching mechanism and changed the micro-environments and conformations of α-glucosidase that led to an aggregation phenomenon. A further molecular docking study provided more information about the interactions of PB2 with the amino acid residues of α-glucosidase. Our results suggest that PB2 is useful for protection against hyperglycemia through inhibiting the activity of α-glucosidase.

Impact of exposure of crude oil and dispersant (COREXIT® EC 9500A) on denitrification and organic matter mineralization in a Louisiana salt marsh sediment.

In response to the 2010 oil spill from the explosion of the Deepwater Horizon oil rig in the Gulf of Mexico, this experiment aims to study the ecological impact of the crude oil and dispersant (COREXIT® EC 9500A) in a coastal salt marsh ecosystem. The marsh sediment was incubated under an anaerobic condition with exposure to the crude oil or/and dispersant. The experiments were conducted in two continuous phases of nitrate addition to study denitrification potential using acetylene blockage technique and organic matter mineralization potential indicated by CO2 production in the sediment. Results show that the oil slightly (with no statistical significance p>0.05) increased both the denitrification and organic matter mineralization activities, likely due to oil components serving as additional organic matter. In contrast, the dispersant significantly (p<0.05) inhibited denitrification, but stimulated organic matter mineralization activities in the sediment due to unknown mechanisms. As a consequence, redox potentials (Eh) were much lower in the dispersant treated systems. The ecological impacts from the dispersant exposure may come from two fronts. First, loss of organic matter from the coastal marsh will threaten the long-term stability of the ecosystem, and the decrease in denitrification activity will weaken the N removal efficiency. Secondly, more reducing conditions developed by the dispersant exposure will likely preserve the oil in the ecosystem for an extended period of time due to weaker oil biodegradation under anaerobic conditions.