Global Analysis of Gene Expression Profiles in Brassica napus Developing Seeds Reveals a Conserved Lipid Metabolism Regulation with Arabidopsis thaliana

In order to study Brassica napus fatty acid （FA） metabolism and relevant regulatory networks, a systematic identification of fatty acid （FA） biosynthesis-related genes was conducted. Following gene identification, gene expression profiles during B. napus seed development and FA metabolism were performed by cDNA chip hybridization （〉8000 EST clones from seed）. The results showed that FA biosynthesis and regulation, and carbon flux, were conserved between B. napus and Arabidopsis. However, a more critical role of starch metabolism was detected for B. napus seed FA metabolism and storage-component accumulation when compared with Arabidopsis. In addition, a crucial stage for the transition of seed-to-sink tissue was 17-21 d after flowering （DAF）, whereas FA biosynthesis-related genes were highly expressed pri- marily at 21 DAF. Hormone （auxin and jasmonate） signaling is found to be important for FA metabolism. This study helps to reveal the global regulatory network of FA metabolism in developing B. napus seeds.

Identification and activity evaluation of Astragalus Radix from different germplasm resources based on specific oligosaccharide fragments

Objective: Based on trifluoroacetic acid(TFA) hydrolysis, polyacrylamide gel electrophoresis(PAGE) and high performance thin layer chromatography(HPTLC) analysis, the carbohydrate responsible for immunomodulatory activity are used as quality indicators for Astragalus Radix(AR).Methods: In this study, 24 batches of AR from different germplasm resources were selected as the research object, and AR polysaccharides were extracted. PAGE and HPTLC methods were used to analyze the partial acid hydrolyzate of AR polysaccharides and obtain a series of saccharide fingerprints. The data were analyzed by principal component analysis to obtain the difference between AR from different germplasm resources.Results: The results showed that trisaccharide and tetrasaccharide could be used as differential fragments to distinguish AR of different cultivation methods;Disaccharides and trisaccharides can be used as differential fragments to distinguish different species of AR. The immunological activity analysis of the specific oligosaccharide fragment of AR showed that the specific oligosaccharide fragment of AR could promote the secretion of TNF-α, IL-1β, IL-6, and NO in THP-1 cells in a concentration-dependent manner.Conclusion: Both PAGE and HPTLC methods can be used to evaluate AR from different germplasm resources. This study laid the foundation for the quality evaluation of AR medicinal herbs.