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FHY3 and its homologous protein FAR1 are the founding members of FRS family. They exhibited diverse and powerful physiological functions during evolution, and participated in the response to multiple abiotic stresses. FRF genes are considered to be truncated FRS family proteins. They competed with FRS for DNA binding sites to regulate gene expression. However, only few studies are available on FRF genes in plants participating in the regulation of abiotic stress. With wide adaptability and high stress-resistance, barley is an excellent candidate for the identification of stress-resistance-related genes. In this study, 22 HvFRFs were detected in barley using bioinformatic analysis from whole genome. According to evolution and conserved motif analysis, the 22 HvFRFs could be divided into subfamilies I and II. Most promoters of subfamily I members contained abscisic acid and methyl jasmonate response elements; however, a large number promoters of subfamily II contained gibberellin and salicylic acid response elements. HvFRF9, one of the members of subfamily II, exhibited a expression advantage in different tissues, and it was most significantly upregulated under drought stress. In-situ PCR revealed that HvFRF9 is mainly expressed in the root epidermal cells, as well as xylem and phloem of roots and leaves, indicating that HvFRF9 may be related to absorption and transportation of water and nutrients. The results of subcellular localization indicated that HvFRF9 was mainly expressed in the nuclei of tobacco epidermal cells and protoplast of arabidopsis. Further, transgenic arabidopsis plants with HvFRF9 overexpression were generated to verify the role of HvFRF9 in drought resistance. Under drought stress, leaf chlorosis and wilting, MDA and O2− contents were significantly lower, meanwhile, fresh weight, root length, PRO content, and SOD, CAT and POD activities were significantly higher in HvFRF9-overexpressing arabidopsis plants than in wild-type plants. Therefore, overexpression of HvFRF9 could significantly enhance the drought resistance in arabidopsis. These results suggested that HvFRF9 may play a key role in drought resistance in barley by increasing the absorption and transportation of water and the activity of antioxidant enzymes. This study provided a theoretical basis for drought resistance in barley and provided new genes for drought resistance breeding.

Glutaredoxins (GRXs) are small-molecular-weight proteins present in a wide range of organisms, and they play a key role in maintaining the redox homeostasis of cells. Most studies on GRXs are conducted in animals and humans, and those conducted on plants are scarce. The number and types of GRX genes vary in different plants. According to the active sites, the GRX family can be further divided into the CPYC, CGFS, and CC subfamilies. The CPYC and CGFS subfamilies are present in eukaryotes. The CC subfamily is exclusively present in higher plants and has the highest number of genes. In this study, 85 GRX genes were identified in common wheat (Triticum aestivum L.) using a bioinformatic method, wherein 12, 9, and 64 belonged to the CPYC, CGFS, and CC subfamilies, respectively. All TaGRX genes were homogeneously distributed in the three subgenomes of wheat. The gene structure analysis revealed that TaGRX members had 1–7 introns. The conserved motif analysis revealed that members of the same TaGRX subfamily had similar motifs. An analysis of cis-regulatory elements of promoters demonstrated that most TaGRX members had auxin-responsive elements; cis-regulatory elements, such as methyl jasmonate (MeJA), MYB, and abscisic acid (ABA), were distributed in all subfamilies, and the cell-cycle regulation element was only observed in the CC and CPYC subfamily members. Additionally, the synteny of the GRX genes in wheat, in wheat and Arabidopsis, and in wheat and barley was analyzed to clarify the evolutionary correlation of TaGRXs. The expression characteristics of TaGRXs were investigated, and TaGRX expression in various tissues and its responses to different abiotic stresses were preliminarily determined. This study provides a reference for the functional analysis of TaGRXs and understanding their role in molecular breeding of wheat.

A new strategy for preparing amphibious ZnO quantum dots (QDs) with blue fluorescence within hyper-branched poly(ethylenimine)s (HPEI) was proposed in this paper. By changing [Zn2+]/[OH−] molar ratio and heating time, ZnO QDs with a quantum yields (QY) of 30% in ethanol were obtained. Benefiting from the amphibious property of HPEI, the ZnO/HPEI nanocomposites in ethanol could be dissolved in chloroform and water, acquiring a QY of 53%, chloroform and 11% in water. By this strategy, the ZnO/HPEI nano-composites could be applied in not only in optoelectronics, but also biomedical fields (such as bio-imaging and gene transfection). The bio-imaging application of water-soluble ZnO/HPEI nanocomposites was investigated and it was found that they could easily be endocytosed by the COS-7 cells, without transfection reagent, and they exhibited excellent biological imaging behavior.

Y2O3 codopedwith different Zr4+ (10% mol, 30%mol, and 49%mol) and constant Er3+ (2% mol) ions were successfully prepared via the laser annealing method. According to the XRD data, the lattice parameters decrease with the increase of Zr4+, and the grain size increases with Zr4+. The crystal space group switches from Ia-3 to Fm-3 m at a Zr4+ concentration of 49% mol. As the concentration of doped Zr4+ increases, the upconversion emission of Er3+ decreases. The nonequivalent substitution of Y3+ by Zr4+ creates lattice defects, which affect the fluorescence intensity of Er3+ ions in the material. The temperature sensing behavior of Y88%Zr10%Er2%O1.55 crystals based on the fluorescence intensity ratio between 4S3/2→4I15/2 and 4I9/2→4I15/2 transitions of Er3+ is studied. The results show that after codoping with Zr4+, the 4S3/2→4I15/2 and 4I9/2→4I15/2 transitions satisfy the Boltzmann distribution formula at temperatures above 333K. And the temperature sensing relative sensitivity can reach 2.96% K-1. [ABSTRACT FROM AUTHOR]