Study on Sparganium stoloniferum from different regions in China based on appearance characters and ISSR markers / 中国中药杂志

Based on the characteristics and ISSR molecular marker technology, the study is aimed to compare and perform genetic diversity analysis on Sparganium stoloniferum from 7 regions. Molecular identification method was established for S. stoloniferum from Hunan province. Differences among Sparganii Rhizoma samples from seven habitats were analyzed via measuring weight, length, width and thickness of them. Genetic diversity of S. stoloniferum from 7 regions was analyzed by screening out primers amplifying clear band and showing rich polymorphism, then a cultivars dendrogram was built. The target primer was screened out, and the specific band was sequenced. Nine ISSR primers were selected to amplified clear band, rich polymorphism. A total of 73 bands were amplified by nine ISSR primers selected from 27 ISSR primers. On average, each primer produced 8.0 bands. A total of 38 bands were polymorphic, which occupied 52.8% of all bands. The cultivars dendrogram showed the genetic similarity was 0.54-0.94. Genetic similarity coefficient of S. stoloniferum from Jiangsu province, Anhui province and Jiangxi province was big, indicating the differences among them were slight on genetic level. S. stoloniferum from Hunan province is quite different from samples from the other six habitats on appea-rance and genetic level. A specific band(327 bp) in S. stoloniferum from Hunan province was obtained via ISSR-857 primer, and was sequenced. According BLASTn database, there were few sequences similar to the gene fragment and had little correlation with the growth process of plant. ISSR molecular marker technology provides a new idea for the identification of S. stoloniferum. This result confirmed the particularity of S. stoloniferum from ancient Jingzhou.

Gene Cloning and Bioinformatics Analysis of Limonene-3-hydroxylase from Schizonepeta tenuifolia / 中国实验方剂学杂志

Objective:This paper aims to clone the cDNA sequence of<italic> limonene</italic>-3-<italic>hydroxylase</italic>（<italic>StL</italic>3<italic>OH</italic>） in <italic>Schizonepeta tenuifolia</italic> and analyze its sequence by bioinformatics. Method:Specific primers were designed based on sequences of<italic> StL</italic>3<italic>OH </italic>gene screened from transcriptome sequencing data of <italic>S. tenuifolia</italic> and the cDNA sequence of <italic>StL</italic>3<italic>OH </italic>gene was cloned by reverse transcription polymerase chain reaction （RT-PCR） and analyzed for its bioinformatics. Result:The <italic>StL3OH</italic> gene cDNA sequence length was 1 598 bp，containing a 1 497 bp long complete open reading frame which encoded 498 amino acids. StL3OH protein had a theoretical relative molecular mass of 56.40 kDa，with a hydrophilic and unstable nature. Bioinformatics analysis showed that StL3OH protein had no signal peptide but had a transmembrane domain which might be located in endoplasmic reticulum. Multiple sequence alignment and cluster analysis showed that the amino acid sequence of MsL3OH protein had a high similarity with StL3OH protein，both of which contained cytochrome P450 heme binding region，belonging to the D subfamily of cytochrome CYP71 family. Codon bias analysis showed that <italic>StL</italic>3<italic>OH</italic> gene preferred guanine/cytosine（G/C） ending codon，with 27 skewed codons， and Nicotiana benthamiana was proven to be the most suitable host for exogenous expression of <italic>StL</italic>3<italic>OH</italic> gene. Conclusion:The cDNA sequence of<italic> StL3OH</italic> gene was cloned from <italic>S. tenuifolia</italic> for the first time，which will provide a basis for further study on the structure and function of StL3OH protein and the regulation mechanism of <italic>StL3OH </italic>gene in the accumulation and biosynthesis of monoterpenes in<italic> S. tenuifolia</italic>.