RESUMEN
The AP2/ERF gene family is one of the largest transcription factor families in the plant kingdom, and plays an important role in response to biological and abiotic stresses, plant hormone responses, and plant growth and development. In this study, the AP2/ERF family of Panax notoginseng was identified by bioinformatics methods, and the physicochemical properties, structure, phylogenetic relationship, expression pattern and function of PnDREB4 gene of the family were analyzed. The results showed that 140 AP2/ERF family members were identified in P. notoginseng, which were divided into DREB, ERF, AP2, RAV and Sololit subgroups. The physicochemical properties and motifs of proteins were similar among the subgroups. There were 34 differentially expressed genes in the AP2/ERF family of Fusarium oxysporum infected P. notoginseng plants, and 19 genes were up-regulated. The expression level of PnDREB84 was up-regulated with the extension of Fusarium oxysporum infection time in the range of 0-96 h. The content of ABA and SA in P. notoginseng plants overexpressing PnDREB84 gene increased after 4 ℃ stress. The results showed that PnDREB84 gene plays a dual regulatory role in the process of biological stress and abiotic stress. PnDREB84 gene can be used as a potential molecular marker for the breeding of new varieties of P. notoginseng. The identification of AP2/ERF transcription factor and function analysis of PnDREB84 gene of P. notoginseng provided data support for the analysis of stress resistance mechanism of P. notoginseng and the breeding of new varieties.
RESUMEN
Acute lung injury (ALI) is a kind of lung disease mainly caused by excessive inflammatory reaction. At present, there is a lack of effective therapeutic drugs in clinic. The aim of this study was to investigate the improvement effect of Panax notoginseng saponins (PNS) on ALI and its potential mechanism. The model of wild-type C57BL/6J mice was established by intratracheal instillation of 50 μL 25 mg·mL-1 lipopolysaccharide (LPS). 24 h later, 200 and 400 mg·kg-1 PNS was given intragastric, respectively. 24 h after administration, the improvement effect of PNS on ALI mice was evaluated by lung function, wet-to-dry weight ratio (W/D), total protein, interleukin 6 (IL6) and tumor necrosis factor α (TNFα) concentration of bronchoalveolar lavage fluid (BALF), expression levels of IL6 and TNFα in lung tissues, pathological changes of lung tissues and expression of inflammatory cells in BALF. The protein expression levels of NF-κB and its upstream kinases in Raw264.7 cells and ALI mice lung tissues were further detected to evaluate the potential mechanism of PNS improving ALI mice. The experimental scheme was approved by the Animal Experiment Ethics Committee of Shanghai University of Traditional Chinese Medicine. It was found that 400 mg·kg-1 PNS could significantly improve the lung function of ALI mice, reduce the contents of W/D, BALF total protein, IL6 and TNFα, neutrophils expression in BALF and the infiltration of inflammatory cells in lung tissue. In Raw264.7 cells and ALI mice lung tissue, PNS significantly reduced the expression of NF-κB, reduced the protein expression and phosphorylation of NF-κB, promoted the expression of IκBα, and inhibited the inflammatory response. This study showed that PNS can improve ALI by inhibiting the activity of NF-κB, inhibiting the release of inflammatory factors and inflammatory cells infiltration, alleviating lung inflammation.
RESUMEN
MYB transcription factors, one of the largest transcription factor families in plants, play an important role in signal transduction, plant growth and plant resistance. In this study a full-length cDNA of the PnMYB1R1 gene was cloned from Panax notoginseng. Sequence analysis, prokaryotic expression and purification, subcellular location, transcriptional activity analysis, tissue-specific analysis and expression analysis under different abiotic stresses was performed. The open reading frame (ORF) of PnMYB1R gene was 738 bp, encoding a protein of 245 amino acids with a predicted molecular mass (MW) of 27.0 kD. The sequence analysis and polygenetic analysis indicated that the PnMYB1R1 protein contains a conserved R3 domain, belonging to TRF-like protein in 1R-MYB-type transcription factors. The recombinant PnMYB1R1 protein was expressed in Escherichia coli BL21(DE3) cells using the prokaryotic expression vector pET28a-PnMYB1R1 and was purified. Subcellular localization analysis showed that PnMYB1R1 was localized in the nucleus. Transcriptional activity analysis indicated that the PnMYB1R1 transcription factor has transcriptional activation activity. Expression analysis indicated that PnMYB1R1 was primarily expressed in roots, followed by stems and leaves, and then rootlets. The expression level of PnMYB1R1 in root, stems, leaves and rootlets was influenced by salt, low temperature and drought treatment, while the abundance of PnMYB1R1 was significantly induced by salt stress in these tissues. These results provide valuable insights into the role of 1R-MYB transcription factors in plant defense.
RESUMEN
Notoginseng (Sanqi), the root of Panax notoginseng (Burk.) F. H. Chen (Araliaceae), is one of the most valuable traditional Chinese medicines (TCM). It has been widely used in China with a long history for treatment of haemorrhage, edema, and cardiovascular disorders. Steamed P. notoginseng has been considered to have stronger therapeutic functions than raw P. notoginseng in the treatment of tumors, cardiovascular diseases, etc. Saponins are the principal chemical and pharmacological constituents in P. notoginseng. Thus, it is of great importance to determine the constituent saponins and determine any differences between fresh P. notoginseng and steamed P. notoginseng. We used a rapid and direct analytical method based on liquid extraction surface analysis combined with mass spectrometry (LESA-MS) to identify saponins in the xylem, phloem and cambium of fresh and steamed P. notoginseng root slices. The results revealed that ginsenosides Rg1, Rb1, Re, Rd, notoginsenoside R1 and their malonyl group versions were most abundant in fresh root slices, while in steamed slices ginsenosides Rg5, Rk1 and other minor polar components could be detected, and the relative content of large polar components was lower. The described method is fast, robust and sensitive and the process does not need traditional and cumbersome pretreatment such as crushing, extraction and separation. It is the first non-destructive study on the differences in saponins between fresh and steamed P. notoginseng root slices.