Bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is an overwhelming disease in rice-growing regions worldwide. Our previous studies revealed that the executor R gene Xa23 confers broad-spectrum disease resistance to all naturally occurring biotypes of Xoo. In this study, comparative transcriptomic profiling of two near-isogenic lines (NILs), CBB23 (harboring Xa23) and JG30 (without Xa23), before and after infection of the Xoo strain, PXO99^A, was done by RNA sequencing, to identify genes associated with the resistance. After high throughput sequencing, 1645 differentially expressed genes (DEGs) were identified between CBB23 and JG30 at different time points. Gene Ontlogy (GO) analysis categorized the DEGs into biological process, molecular function, and cellular component. KEGG analysis categorized the DEGs into different pathways, and phenylpropanoid biosynthesis was the most prominent pathway, followed by biosynthesis of plant hormones, flavonoid biosynthesis, and glycolysis/gluconeogenesis. Further analysis led to the identification of differentially expressed transcription factors (TFs) and different kinase responsive genes in CBB23, than that in JG30. Besides TFs and kinase responsive genes, DEGs related to ethylene, jasmonic acid, and secondary metabolites were also identified in both genotypes after PXO99^A infection. The data of DEGs are a precious resource for further clarifying the network of Xa23-mediated resistance.

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HIV-1 glycoprotein 41 (gp41) mediates viral entry into host cells by coupling its folding energy to membrane fusion. Gp41 folding is blocked by fusion inhibitors, including the commercial drug T20, to treat HIV/AIDS. However, gp41 folding intermediates, energy, and kinetics are poorly understood. Here, we identified the folding intermediates of a single gp41 trimer-of-hairpins and measured their associated energy and kinetics using high-resolution optical tweezers. We found that folding of gp41 hairpins was energetically independent but kinetically coupled: Each hairpin contributed a folding energy of ∼−23 k_BT, but folding of one hairpin successively accelerated the folding rate of the next one by ∼20-fold. Membrane-mimicking micelles slowed down gp41 folding and reduced the stability of the six-helix bundle. However, the stability was restored by cooperative folding of the membrane-proximal external region. Surprisingly, T20 strongly inhibited gp41 folding by actively displacing the C-terminal hairpin strand in a force-dependent manner. The inhibition was abolished by a T20-resistant gp41 mutation. The energetics and kinetics of gp41 folding established by us provides a basis to understand viral membrane fusion, infection, and therapeutic intervention.

Water-soluble polysaccharide from tea plant flower (TFP) was screened for its biological and biophysical effects. TFP-1, one of the major constituents, yielded after removing the proteins and purification by Sephadex G-100 (Sigma-Aldrich Pty Ltd., Castle Hill, Australia). It was subjected to chemical identification and the result indicated its average molecular weight (132 kDa) and its formation which consisted of xylose, glucose, arabinose and galactose with the molar ratio of 1.0: 2.9: 4.6: 21.8. Presence of TFP-1 displayed reactive oxygen radicals scavenging activity and it showed dose-dependent antioxidant activity by comparing with three commonly used antioxidants. The research showed that administration of TFP-1 for 28d continuously was found not only to be protective on liver lipid peroxidation induced by bromobenzene in mice through increasing the activity of superoxidase dismutase, total antioxidant capacity, but also markedly to attenuate the enhancement of malondialdehyde content in dose-dependent manner. Altogether, these results suggest that TFP-1 could be considered as a potential antioxidant. PRACTICAL APPLICATIONS The resources of tea (Camellia sinesis) flower is abundant in China with low utilization, as tea farmers buried their trim and had little utilization of them. Tea flower is rich in proteins, tea polysaccharides, amino acids, vitamins and other active substances, and its toxicological safety and pesticide residues in volume come up to European standards. At present, commonly low-grade tea is preferred to tea flowers to extract the tea polysaccharide. To make full use of the abandoned tea flower resource to extract polysaccharides can greatly reduce the cost of tea products. Moreover, the research on antioxidant activity of tea flower polysaccharide provides a scientific basis for tea flower as a cheap and effective antioxidant product, additives in food and cosmetic. Secondly, the use of tea flower can also reduce the consumption of tea nutrient and make it turn to vegetative growth, which can improve yield and quality of tea.

Subcutaneous adipose tissue is a loose connective tissue specializing in the regulation of energy storage and metabolization. In domesticated pigs (Sus scrofa), the temporal development of subcutaneous adipose tissue is critical for meat production. However, the regulation of adipose tissue development remains unclear. Here, the subcutaneous adipose tissue development was characterized and compared in lean (Danish-Landrace) and obese (Min) pigs at juvenile and the juvenile-to-adult growth stages. Using RNA sequencing, we profiled the transcriptome of subcutaneous adipose tissue isolated from 4- and 16-week-old pigs and identified 24,718 expressed transcription units. Of them, 6327 genes were differentially expressed between the breeds and/or developmental stages. Compared with obese pigs, upregulated genes in lean pigs showed significant function and pathway enrichment in fatty acid degradation and mitochondrial functions. Further analysis uncovered the distinct usage preferences of the three alternative peroxisome proliferator-activated receptor γ (PPARγ) promoters associated with the development of subcutaneous adipose tissue in both breeds. Transcriptome analysis of subcutaneous adipose tissue in lean and obese pigs suggested that marker-assisted selection of fatty acid degradation and PPARγ signaling pathways could be important directions for future pork quality improvement and modern breeding.