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Abiotic stresses are major environmental factors that affect agricultural productivity worldwide. NAC transcription factors play pivotal roles in abiotic stress signaling in plants. As a staple crop, wheat production is severely constrained by abiotic stresses whereas only a few NAC transcription factors have been characterized functionally. To promote the application of NAC genes in wheat improvement by biotechnology, a novel NAC gene designated TaNAC67 was characterized in common wheat. To determine its role, transgenic Arabidopsis overexpressing TaNAC67-GFP controlled by the CaMV-35S promoter was generated and subjected to various abiotic stresses for morphological and physiological assays. Gene expression showed that TaNAC67 was involved in response to drought, salt, cold and ABA treatments. Localization assays revealed that TaNAC67 localized in the nucleus. Morphological analysis indicated the transgenics had enhanced tolerances to drought, salt and freezing stresses, simultaneously supported by enhanced expression of multiple abiotic stress responsive genes and improved physiological traits, including strengthened cell membrane stability, retention of higher chlorophyll contents and Na+ efflux rates, improved photosynthetic potential, and enhanced water retention capability. Overexpression of TaNAC67 resulted in pronounced enhanced tolerances to drought, salt and freezing stresses, therefore it has potential for utilization in transgenic breeding to improve abiotic stress tolerance in crops.

Environmental stresses such as drought, salinity, and cold are major adverse factors that significantly affect agricultural productivity. Protein phosphorylation/dephosphorylation is a major signalling event induced by osmotic stress in higher plants. Sucrose non-fermenting 1-related protein kinase 2 (SnRK2) family members play essential roles in the response to hyperosmotic stresses in plants. In this study, the TaSnRK2.3 gene, a novel SnRK2 member was cloned, and three copies located on chromosomes 1A, 1B, and 1D were identified in common wheat. TaSnRK2.3 was strongly expressed in leaves, and responded to polyethylene glycol, NaCl, abscisic acid, and cold stresses. To characterize its function, transgenic Arabidopsis overexpressing TaSnRK2.3–GFP controlled by the cauliflower mosaic virus 35S promoter was generated and subjected to severe abiotic stresses. Overexpression of TaSnRK2.3 resulted in an improved root system and significantly enhanced tolerance to drought, salt, and freezing stresses, simultaneously demonstrated by enhanced expression of abiotic stress-responsive genes and ameliorative physiological indices, including a decreased rate of water loss, enhanced cell membrane stability, improved photosynthetic potential, and significantly increased osmotic potential and free proline content under normal and/or stressed conditions. These results demonstrate that TaSnRK2.3 is a multifunctional regulator, with potential for utilization in transgenic breeding for improved abiotic stress tolerance in crop plants.

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Salix matsudana is a deciduous, rapidly growing willow species commonly cultivated in China, which can tolerate drought, salt, and heavy metal stress conditions. Selection of suitable reference genes for quantitative real-time PCR is important for normalizing the expression of the key genes associated with various stresses. To validate suitable reference genes, we selected 11 candidate reference genes (five traditional housekeeping genes and six novel genes) and analyzed their expression stability in various samples, including different tissues and under different abiotic stress treatments. The expression of these genes was determined using five programs—geNorm, NormFinder, BestKeeper, ΔCt, and RefFinder. The results showed that α-TUB2 (alpha-tubulin 2) and DnaJ (chaperone protein DnaJ 49) were the most stable reference genes across all the tested samples. We measured the expression profiles of the defense response gene SmCAT (catalase) using the two most stable and one least stable reference genes in all samples of S. matsudana. The relative quantification of SmCAT varied greatly according to the different reference genes. We propose that α-TUB2 and DnaJ should be the preferred reference genes for normalization and quantification of transcript levels in future gene expression studies in willow species under various abiotic stress conditions.

MicroRNAs play an essential role in stroke pathology. Here, we investigated the role of a newly identified microRNA, miR-3473b, in stroke pathology. The expression of miR-3473b was upregulated in the cortex and striatum in mice following transient middle cerebral artery occlusion (MCAO). Intracerebroventricular injection of the miR-3473b antagomir prior to MCAO remarkably attenuated ischemia-induced expression of miR-3473b and pro-inflammatory factors in the ischemic brain and decreased infarct volumes in mice following MCAO. Using in vitro approaches, we showed that the miR-3473b antagomir reduced the mRNA and protein levels of pro-inflammatory factors (iNOS, COX-2, TNF-α, and IL-6) in BV2 microglial cells subjected to LPS stimulation. The miR-3473b antagomir also decreased the expression of pro-inflammatory factors in BV2 cells activated with conditioned medium collected from oxygen-glucose deprivation (OGD)-treated neurons. Suppressor of cytokine signaling 3 (SOCS3), a physiological regulator of innate and adaptive immunity, was predicted to be a potential target of miR-3473b. We verified that the miR-3473b mimic decreased SOCS3 expression in BV2 cells. Meanwhile, the miR-3473b antagomir significantly increased both SOCS3 mRNA and protein levels in the BV2 cells treated with LPS as well as in the ischemic brain. By using the dual luciferase assay, we further showed that the 3′-untranslational region of SOCS3 was directly targeted by miR-3473b. In conclusion, induction of miR-3473b, which is likely targeted to SOCS3, contributes to stroke pathogenesis by enhancing post-stroke neuroinflammation injury.

Efficient Si/organic hybrid solar cells were fabricated with dimethyl sulfoxide (DMSO) and surfactant-doped poly(3,4-ethylenedioxythiophene): polystyrene (PEDOT:PSS). A post-treatment on PEDOT:PSS films with polar solvent was performed to increase the device performance. We found that the performance of hybrid solar cells increase with the polarity of solvent. A high conductivity of 1105 S cm − 1 of PEDOT:PSS was achieved by adopting methanol treatment, and the best efficiency of corresponding hybrid solar cells reaches 12.22%. X-ray photoelectron spectroscopy (XPS) and RAMAN spectroscopy were utilized to conform to component changes of PEDOT:PSS films after solvent treatment. It was found that the removal of the insulator PSS from the film and the conformational changes are the determinants for the device performance enhancement. Electrochemical impedance spectroscopy (EIS) was used to investigate the recombination resistance and capacitance of methanol-treated and untreated hybrid solar cells, indicating that methanol-treated devices had a larger recombination resistance and capacitance. Our findings bring a simple and efficient way for improving the performance of hybrid solar cell.