Use of RNAi With OsMYB76R as a Reporter for Candidate Genes Can Efficiently Create and Verify Gametophytic Male Sterility in Rice.

Gametophytic male sterility (GMS) plays an important role in the study of pollen development and seed propagation of recessive nuclear male sterile lines insensitive to the environmental conditions in hybrid rice breeding. Since the inherent phenotypic and genetic characteristics of GMS, it is very difficult to find and identify the GMS mutants. However, due to the abundance of gene transcription data, a large number of pollen-specific genes have been found, and most of them may be associated with GMS. To promote the study of these genes in pollen development and heterosis utilization, in this study, an easy and efficient method of creating and identifying GMS was established using RNAi and OsMYB76R as a reporter. First, the OsC1/OsMYB76 gene involved in anthocyanin synthesis was modified, and we have validated that the modified OsMYB76R is workable as the same as the pre-modified OsMYB76 gene. Then, the ascorbic acid oxidase gene OsPTD1 was downregulated using RNAi, driven by its own promoter that resulted in abnormal pollen tube growth. Finally, the RNAi elements were linked with OsMYB76R and transformed into an osmyb76 mutant, and the distortion of purple color segregation was found in T1 and F1 generations. This indicates that the OsPTD1 GMS was prepared successfully. Compared to current methods, there are several advantages to this method. First, time is saved in material preparation, as one generation less needs to be compared than in the conventional method, and mutation screening can be avoided. In addition, for identification, the cost is lower; PCR, electrophoresis, and other processes are not needed; and no expensive chemicals or instruments are required. Finally, the results are more accurate, with much lower background effects, and no damage to the plant. The result is an easy, efficient, low-cost, and accurate method of preparing and identifying GMS genes.

Analgesic effect and related amino acids regulation of ginsenoside Rg3 in mouse pain models.

AIMS: The present study aims to evaluate the analgesic effect of ginsenoside Rg3 in different mouse pain models. MAIN METHODS: Formalin-, carrageenan- and S180 tumor cells induced mouse pain models were built in the study. The licking and biting time and PEG2 contents in the inflammatory sites were measured. The excitatory and inhibitory amino acids in the brains were determined by pre-column derivation FLD-HPLC method. KEY FINDING: We have found that ginsenoside Rg3 treated the pain phases and decreased the PGE2 in formalin and carrageenan induced models, respectively. It significantly increased the contents of EAAs (Asp and Glu) in the brains of S180 tumor inducing pain mice, meanwhile, the IAAs (Gly, Tau and GABA) decreased. SIGNIFICANCE: Our results revealed that ginsenoside Rg3 acted central and peripheral analgesic effect and regulated the inflammatory factors and pain-related amino acids. It could re-balance the abnormal EAAs/IAAs value when the pain occurred. The analgesic mechanism and the clinical application of ginsenoside Rg3 need be evaluated furtherly.

Composition analysis and antioxidant activity of essential oils, lipids and polysaccharides in different phenotypes of Lepidium meyenii.

The phenotypes of Lepidium meyenii (Maca) relate to their difference of chemical compositions and biological activities. Essential oils, lipids and polysaccharides are the main active components in Maca, all of which showed potential antioxidant effect. The essential oil, lipid and polysaccharide compositions were analyzed by GC-MS after the samples were properly pre-treated from yellow, red and black Maca. The antioxidant properties of the three types of components were examined using the DPPH scavenging assay. The correlation of main compositions and the antioxidant activities was evaluated by a statistical method. In Maca essential oil, lipid and polysaccharide samples, thirty volatile compounds, twenty-nine fatty acids and six monosaccharides had been detected, in which benzeneacetonitrile, unsaturation fatty acids and mannose were predominant ingredients, respectively. In three types of components, the DPPH scavenging effect of essential oil was stronger. All of black Maca essential oil, lipid and polysaccharide showed higher effect than yellow and red phenotype. The total activity of the three types of components showed about 60% of the antioxidant activity of entire Maca. Canonical correlation analysis (CCA) results showed that four essential oils, three fatty acids and four monosaccharaides were positively related to the antioxidant activity. The research is helpful to address the quality attributes and the comprehensive application of different phenotypes of Maca.

Binding effect of fluorescence labeled glycyrrhetinic acid with GA receptors in hepatocellular carcinoma cells.

Glycyrrhetinic acid (GA) is a natural active component from licorice, which is broadly used in traditional Chinese medicine. Lots of glycyrrhetinic acid receptors (GA-R) are proved to locate on the surface of liver cells. Many reports about the hepatocellular carcinoma (HCC) treatment were dependent on GA modified carriers. However, the reality of GA-R in HCC cells was not clear. In this paper, 18ß-glycyrrhetinic acid (18ß-GA) was labeled with fluorescence (FITC) by chemical synthesis. Together with the binding effect of fluorescence labeled glycyrrhetinic acid (FITC-GA), the competitive action of 18ß-GA with GA-R was investigated in HCC cells. The results showed that in HepG2 cells, 18ß-GA and FITC-GA presented similar cytotoxicity. The specific binding saturation of GA showed the dissociation constant (Kd) was 7.457±2.122pmol/L and the maximum binding counts (Bmax) was 2.385±0.175pmol/2.5×106 cells, respectively. FITC-GA bound to cytomembrane specifically and 18ß-GA competed to bind the sites significantly in HepG2 cells. Therefore, there is binding effect between fluorescence labeled GA and GA-R. The GA-R on HCC cells is confirmed as expected, which provides a useful reference of active target modified by GA and a novel approach for receptors and ligands study.