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Abstract Previous studies in Arabidopsis reported that the PPR protein SOAR1 plays critical roles in plant response to salt stress. In this study, we reported that expression of the Arabidopsis SOAR1 (AtSOAR1) in rice significantly enhanced salt tolerance at seedling growth stage and promoted grain productivity under salt stress without affecting plant productivity under non-stressful conditions. The transgenic rice lines expressing AtSOAR1 exhibited increased ABA sensitivity in ABA-induced inhibition of seedling growth, and showed altered transcription and splicing of numerous genes associated with salt stress, which may explain salt tolerance of the transgenic plants. Further, we overexpressed the homologous gene of SOAR1 in rice, OsSOAR1, and showed that transgenic plants overexpressing OsSOAR1 enhanced salt tolerance at seedling growth stage. Five salt- and other abiotic stress-induced SOAR1-like PPRs were also identified. These data showed that the SOAR1-like PPR proteins are positively involved in plant response to salt stress and may be used for crop improvement in rice under salinity conditions through transgenic manipulation.

Marek's disease (MD), an immunosuppressive disease induced by Marek's disease virus (MDV), provides an ideal model for studying diseases caused by a carcinogenic virus. CD79B is a B-cell antigen receptor complex-associated protein β-chain precursor which is involved in the activation, proliferation, differentiation of B-cell and the transmission of downstream signals. This study analyzed CD79B gene mRNA expression and methylation by two schemes #20 (5´ flanking to intron 1) and #27 (intron 2 to intron 3), between MDV-infected tumorous spleens (TS) and non-infected spleens (NS). Results showed that average methylation levels of CpGs in #20 and #27 were higher in TS than in NS (P

ObjectiveThis study aimed to explore the roles of PARP1 mRNA and protein expression in platinum resistance and prognosis of EOC patients, and reveal the different roles of PARP1 protein in epithelial tumor and stroma cells.MethodsThe PARP1 mRNA expression of the EOC tissues was examined by RT-qPCR. The impacts of PARP1 expression on prognosis were measured by Kaplan-Meier and Cox regression. Receiver operating characteristic (ROC) curve analysis was employed for calculating the diagnostic value of PARP1 on platinum resistance. The microarray of formalin-fixed, paraffin-embedded (FFPE) tissues was processed for multiplex immunofluorescence to detect the protein levels of PARP1 and cytokeratin (CK).ResultsThe PARP1mRNA expression of EOC patients was higher in the platinum-resistant group compared with the sensitive group (P

Marek's disease (MD), a highly cell-associated and contagious disease of chickens caused by Marek's disease virus (MDV) can result in neural lesions, immunosuppression and neoplasia in chicken. The Meq gene is an important oncogene in the MDV genome, and it is expressed highly in MD tumor tissues and MD T-lymphoblastoid cell lines. An experiment was conducted to elucidate the role of Meq in MD tumor transformation. RNA interference technology was used to block its expression, and then analyzed the biological effects of Meq knockdown on the MD tumor cell line MSB1. A small interfering RNA with an interference efficiency of 70% (P0.05). B-cell lymphoma 2 gene (BCL2) was anti-apoptotic and caspase-6 was the effector in the apoptosis pathway. The activity of caspase-6 was upregulated (P0.05) post-Meq knockdown, but the expression of two genes (matrix metalloproteinase 2 (MMP2) and MMP9) that are correlated closely to cell invasion was downregulated (P

To understand the effect of nitrogen (N) fertilizer on rice (Oryza sativa L.) eating and cooking quality (ECQ). Here, we investigated the ECQ attributes, physicochemical foundation of ECQ, and amylopectin fine structure of two Waxy (Wx) alleles japonica rice cultivars Nanjing 9108 (NJ9108) and Huaidao 5 (HD5) under four N rates (0, 150, 300, and 450 kg ha−1). Sensory and pasting properties of the two cultivars varied depending on N rates. Compared with the control (0 kg ha−1), the overall eating quality and sensory value were significantly decreased under the N rates of 300 and 450 kg ha−1. Further, conventional descriptive analysis showed that the stickiness and retrogradation of cooked rice were significantly decreased. These results indicated that application of N fertilizer seems to affect the texture of cooked rice, causing it to be less sticky, lowering its retrogradation, and consequently reducing its palatability. Results from rapid visco analyzer (RVA) revealed that the peak and breakdown viscosities significantly decreased, while the setback viscosity and peak time increased under the N rates of 300 and 450 kg ha−1. However, no significant difference was observed when the N rate was 150 kg ha−1, indicating that less N fertilization can maintain rice ECQ. As the N rate increasing, protein content increased, whereas apparent amylose content, starch content, and gel consistency almost unchanged. Interestingly, compared with the control, under N treatments, the percentage of short amylopectin branches in NJ9108 was decreased, but increased in HD5, as controlled by amylopectin synthesis-related genes. Notably, SSI and BEIIb were down-regulated in NJ9108, whereas BEIIb was up-regulated in HD5. Thus, the palatability of both rice cultivars was significantly decreased under excessive N fertilization as a consequence of reduced stickiness and retrogradation of the cooked rice, which might have resulted from an elevated protein content and altered amylopectin fine structure. In addition, amylopectin synthesis appeared to be affected by N fertilizer and the genotype of the rice cultivar.

A novel method for producing high-quality lycopene from Blakeslea trispora through submerged fermentation is studied. 2-Isopropylimidazole at 300 mg/L completely inhibited lycopene cyclase, which limited the accumulation of γ-carotene and β-carotene. 2-Isopropylimidazole also intensified the metabolic flow of lycopene by increasing the expression levels of key enzymes involved in the lycopene synthetic pathway. Ketoconazole at 20 mg/L reduced the metabolic flow of ergosterol and increased lycopene content and production by 76.6% and 64.3%, respectively. Lycopene accounted for approximately 96% of the total carotenoids, whereas cis-lycopene accounted for approximately 35% of the total lycopene. The content and nutritional quality of lycopene from B. trispora were higher than those of lycopene from tomatoes. B. trispora is an ideal source of natural lycopene.

Browning phenomena are ubiquitous in plant cell cultures that severely hamper scientific research and widespread application of plant cell cultures. Up to now, this problem still has not been well controlled due to the unclear browning mechanisms in plant cell cultures. In this paper, the mechanisms were investigated using two typical materials with severe browning phenomena, Taxus chinensis and Glycyrrhiza inflata cells. Our results illustrated that the browning is attributed to a physiological enzymatic reaction, and phenolic biosynthesis regulated by sugar plays a decisive role in the browning. Furthermore, to confirm the specific compounds which participate in the enzymatic browning reaction, transcriptional profile and metabolites of T. chinensis cells, and UV scanning and high-performance liquid chromatography-mass spectrometry (HPLC-MS) profile of the browning compounds extracted from the brown-turned medium were analyzed, flavonoids derived from phenylpropanoid pathway were found to be the main compounds, andmyricetin and quercetin were deduced to be the main substrates of the browning reaction. Inhibition of flavonoid biosynthesis can prevent the browning occurrence, and the browning is effectively controlled via blocking flavonoid biosynthesis by gibberellic acid (GA3) as an inhibitor, which further confirms that flavonoids mainly contribute to the browning. On the basis above, a model elucidating enzymatic browning mechanisms in plant cell cultures was put forward, and effective control approaches were presented. [ABSTRACT FROM AUTHOR]

Background: Methyl jasmonate (MeJA) has been successfully used as an effective elicitor to enhance production of taxol and other taxanes in cultured Taxus cells. However the mechanism of MeJA-mediated taxane biosynthesis remains unclear. Genomic information for species in the genus Taxus is currently unavailable. Therefore, information about the transcriptome of Taxus cells and specifically, description of changes in gene expression in response to MeJA, is needed for the better exploration of the biological mechanisms of MeJA-mediated taxane biosynthesis. Results: In this research, the transcriptome profiles of T. chinensis cells at 16 hours (T16) after MeJA treatment and of mock-treated cells (T0) were analyzed by "RNA-seq" to investigate the transcriptional alterations of Taxus cell in response to MeJA elicitation. More than 58 million reads (200 bp in length) of cDNA from both samples were generated, and 46,581 unigenes were found. There were 13,469 genes found to be expressed differentially between the two timepoints, including all of the known jasmonate (JA) biosynthesis/JA signaling pathway genes and taxol-related genes. The qRT-PCR results showed that the expression profiles of 12 randomly selected DEGs and 10 taxol biosynthesis genes were found to be consistent with the RNA-Seq data. MeJA appeared to stimulate a large number of genes involved in several relevant functional categories, such as plant hormone biosynthesis and phenylpropanoid biosynthesis. Additionally, many genes encoding transcription factors were shown to respond to MeJA elicitation. Conclusions: The results of a transcriptome analysis suggest that exogenous application of MeJA could induce JA biosynthesis/JA signaling pathway/defence responses, activate a series of transcription factors, as well as increase expression of genes in the terpenoid biosynthesis pathway responsible for taxol synthesis. This comprehensive description of gene expression information could greatly facilitate our understanding of the molecular mechanisms of MeJA-mediated taxane biosynthesis in Taxus cells. [ABSTRACT FROM AUTHOR]

Taxus chinensis suspension cells were transformed by the Agrobacterium-mediated transformation method to overexpress the dbat gene coding for 10-deacetylbaccatin III-10 β- O-acetyltransferase, a key enzyme for taxol biosynthesis. A. tumefaciens strain LBA4404 harboring either pCAMBIA1303 or the recombinant plasmid p1303- SdbatN was used. Both plasmids harbored the hygromycin phosphotransferase gene ( hptII) and gusA- mgfp5 gene as selectable markers, but the latter plasmid also harbored the dbat gene in the T-DNA region. The transgenic T. chinensis cells had been maintained in modified Gamborg's B5 medium supplemented with hygromycin for more than 14 months and were subcultured at 4-week intervals. The selected transgenic cells were identified by PCR, Southern blot analysis, β-glucuronidase assay and western blot analysis, and the results showed that the transgenes were integrated in the chromosomal DNA of T. chinensis cells with single-copy style, and that the gusA- mgfp5 reporter gene was expressed in the transgenic cells. The dbat mRNA expression level in the p1303- SdbatN-transgenic T. chinensis cells tested by real-time quantitative PCR was 5.3 ± 0.6 times that of the non-transformed cells. Taxol yield of the p1303- SdbatN-transgenic T. chinensis cells was about 1.7 times that of the non-transformed cells. These results suggest that the overexpression of dbat gene in transgenic T. chinensis cells leads to increased taxol yield. [ABSTRACT FROM AUTHOR]

Pyracantha fortuneana fruit is a potential source of nutraceutical and therapeutic agents. We investigated the effects of P. fortuneana fruit extract (PFE) on hyperlipidaemia, obesity, and oxidative stress in rodents. PFE significantly decreased body weight, triacylglycerol, total cholesterol, low-density lipoprotein-cholesterol, and malondialdehyde levels. By contrast, PFE elevated high-density lipoprotein-cholesterol levels, glutathione peroxidase, and superoxide dismutase activities in both preventive and therapeutic rodent groups. These results indicate that the amelioration of PFE on hyperlipidaemia and obesity was highly associated with the improvement of endogenous antioxidant activity. Polyphenols and saponins were quantified by spectrophotometric and HPLC methods. Several new saponin compounds were identified by liquid chromatography and tandem mass spectrometry as ursolic acid (UA) derivatives. The quercetin, rutin, and procyanidin treatments in HepG2 cells showed increases in low-density lipoprotein receptor activity and apolipoprotein-A1, but UA less affected these protein activities. Therefore, PFE could be promising in ameliorating chronic metabolic diseases via multiple constituent synergies.

Optimized solid–liquid extraction conditions by response surface methodology (RSM) and optimal solvent selectivity liquid–liquid fractionation by mixture design were studied for process of Pyracantha fortuneana fruits (PFF) healthy products. A combination of total polyphenolic content (TPC), total antioxidant activity (TAA) and chromatographic profiling was used to evaluate the optimization. RSM results were ethanol concentration, 71%; extraction temperature, 51 °C; and pH solution, 3.2. The mixture design indicated that the fraction with the highest TAA and TPC was directed to ethyl-acetate phase. The fractions of water-soluble and n-butylalcohol-soluble were rich in TAA and TPC compared with the starting row of PFF. Twenty-seven polyphenols were detected in chromatographic profilings, most of which were reported for the first time in this study. The improvements of accessibility in the optimized fractions suggest their flexible applicabilities for nutraceutical food industries. This study may be crucial approach for all similar natural functional product optimization.