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Molecular Cloning, Escherichia coli Expression and Genomic Organization of squalene synthase Gene from Artemisia annua

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Acta Botanica Sinica 2003年第5期45卷 608-613页

作者：刘彦叶和春王红李国凤中国科学院植物研究所光合作用与环境分子生理重点实验室北京100093

A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 39%a identical to that of squalene synthases from Arabidopsis thaliana, tobacco, human and yeast, respectively. The AaSQS genomic DNA has a complex organization containing 14 exons and 13 introns. Full-length or C-terminal truncated cDNA was subcloned into prokaryotic expression vector pET30a and the constructed plasmid was introduced to Escherichia coli strain BL21 (DE3) for induced overexpression. No squalene synthase protein with expected molecular mass was observed in E. cola containing the putative full-length squalene synthase cDNA, however, overexpression in E. coli was achieved by truncating 30 amino acids of hydrophobic region at the carboxy terminus.

关键词： Artemisia annua squalene synthase Escherachia coli overexpression genomic organization cloning

Cloning and Characterization of squalene synthase（SQS） Gene from Ganoderma lucidum

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Cloning and Characterization of Squalene Synthase（SQS） Gen...

cDNA Cloning and Sequencing of squalene synthase of Artemisa apiacea

第八届海峡两岸菌物学学术研讨会

作者： ZHAO Ming-wen~(1*),WANG Nan~2 (1.College of Life Sciences,Nanjing Agricultural University,Key Laboratory of Microbiological Engineering of Agricultural Environment,Ministry of Agriculture,Nanjing 210095,Jiangsu 2.Institute of Edible Fungi,Shanghai Academy of Agricultural Sciences,Key Laboratory of Agriculture Genetics and Breeding of Shanghai,P.R.China)

＜正＞This report provides the complete nucleotide sequences of the full-length cDNA encoding squalene synthase（SQS） and its genomic DNA sequence from a triterpene-producing fungus,Ganoderma *** cDNA of the squalene synthase（SQS）（GenBank accession number:DQ494674） was found to contain an open reading frame（ORF） of 1404 bp encoding a 468-amino-acid-polypeptide,while the SQS genomic DNA sequence （GenBank accession number:DQ494675） consisted of 1984 bp and contained four exons and three *** one gene copy was present in the *** *** deduced amino acid sequence of *** squalene synthase（Gl-SQS） exhibited a high homology with other fungal squalene synthase genes and contained six conserved domains.A phylogenetic analysis revealed that *** SQS belonged to the fungi SQS group,and was more closely related to the SQS of *** than to those of other fungi.A gene expression analysis showed that the expression level was relatively low in mycelia incubated for 12 days,increased after 14 to 20 days of incubation,and reached a relatively high level in the mushroom *** complementation of Gl-SQS in a SQS-deficient strain of Saccharomyces cerevisiae confirmed that the cloned cDNA encoded a squalene synthase.

关键词： cDNA cloning Ganoderma lucidum squalene synthase functional complement

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Agricultural Science & Technology 2010年第2期11卷 80-83,86页

作者：常晶郭春华尹永志江明锋喻麟徐亚欧郑玉才西南民族大学生命科学与技术学院四川成都610041 国家民委与教育部共建动物科学重点实验室四川成都610041 成都大帝汉克生物科技有限公司四川成都611130

[Objective] cDNA from squalene synthase was cloned and sequenced.[Method] A pair of specific primers was designed according to the cDNA gene sequence of squalene synthase published in *** RNA was extracted from the cell of Artemisia *** genes of squalene synthase were amplified by using *** was connected with pMD19-T vector and the cloned fragment sequences were analyzed.[Result] SS gene with the whole length of 1 257 bp was amplified and the fragment encoded 418 amino *** homo...

关键词： Artemisia apiacea squalene synthase Sequence analysis

Effects of Arsenic Treatments on Saponin Content and Heterogeneity Extracted from Rhizome and Main Root of Panax notoginseng Plants Grown in Shaded Field

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Journal of Geoscience and Environment Protection 2016年第7期4卷 15-27页

作者： Yanqun Zu Jinjin Sun Ni Ma Qiang Min Guangquan Feng Jiong Wu Yuan Li College of Resources and Environment Yunnan Agricultural University Kunmin Yunnan Province China Wenshan Sanqi Research Institute Wenshan College Wenshan Yunnan Province China

As contamination is one of important factors to Panax notoginseng quality and safety. Saponin is one of important compounds with the medicinal values of P. notoginseng. The impact of soil As on production of saponin of P. notoginseng knew very little. This study was performed to determine content and heterogeneity of saponins from P. notoginseng and its mechanisms upon treatments with different concentration levels of As in soil. Plants of P. notoginseng were treated with arsenic [As (V)] at 0, 20, 80, 140, 20 and 260 mg/kg concentration levels which were supplied as sodium arsenate (Na3AsO4). These experimental plants were grown in shade condition in a greenhouse. Plants were harvested at vigorous vegetative growth and fruit ripening stages, separately. Effects of As treatments on saponin content, and heterogeneity of monomers in the mixtures of notoginesenosides and ginsenosides, enzymatic activity and gene expression level of squalene synthetase were determined for rhizome and main root tissues. Results show that:(1) Of all the As treatments from the lowest to the highest concentration levels, the As content in both rhizome and main roots from As-treated plants was within the standard level for superior products derived from P. notoginseng. The content of notoginsenosides from all tissues except the main roots at fruit ripening stage, was 5% higher than the standard level specified in the Chinese Pharmacopoeia;(2) The treatment of As at 20 mg/kg led to an 3.5% - 183.9% increases in total notoginesenosides content in rhizome and main roots, respectively. Treatments with the highest As concentration at 260 mg/kg resulted in a significant decline in total notoginsenosides content, and lower enzymatic activity and gene expression levels of squalene synthetase;(3) Under As treatment conditions, the ratio of Rb1/Rg1 decreased but the ratio of (Rb1 + Rg1)/R1 increased in both rhizomes and main roots. Conclusively, this study d

关键词： Panax notoginseng Saponin As squalene synthase Gene Expression

Effect of light quality on total gypenosides accumulation and related key enzyme gene expression in Gynostemma pentaphyllum

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Chinese Herbal Medicines 2018年第1期10卷 34-39页

作者： ting wang xiang-rong tian xiao-yu wu zhun luo gui li xiao-lie peng shi-biao liu College Biology and Environmental Science Jishou UniversityJishou 416000China

Objective： Light quality has effect on the accumulation of gypenosides in the medicinal plant Gynosternma pentaphyllum in the family Cucurbitaceae, while the squalene synthase （SS） and squalene epoxidase （SE） are the key enzymes for gypenoside biosynthesis, The objective of this study was to elucidate the rela- tionship between light quality and biosynthesis key enzyme involving the regulation of gypenoside accu- mulation. Methods： The content of total gypenosides was measured by colorimetric method and the expression of SS and SE gene was determined by quantitative Real-time PCR in the seedlings of G. pentaphyllum which were grown with different light quality. Results： Light quality showed remarkable impacts on the accumulation of total gypenosides. The highest content of total gypenosides in the plant under red light condition was determined, followed by blue light and white light, while the lowest content was recorded under dark condition, qRT-PCR analysis proved that the expression levels of SS and SE genes were also affected by light quality. The high-level gene expressions of SS and SE were found in the plant under red light condition, followed by blue light, with the least content in darkness. The statistical analysis revealed that the total gypenosides were significantly different in different light treatment and the content of total gypenosides was positively related to the expression of SS and SE genes. Conclusions： Light quality regulates gypenoside accumulation via altering the expression of SS and SE in G. pentaphyllum.

关键词： gene expression Gynostemma pentaphyllum Gypenosides light quality squalene epoxidase squalene synthase

RNA-Seq of Gynostemma Pentaphyllum to Identify Genes and Enzymes Involved in Triterpenoid Biosynthesis

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RNA-Seq of Gynostemma Pentaphyllum to Identify Genes and Enz...