title: Strengthening Triterpene Saponins Biosynthesis by Over-Expression of Farnesyl Pyrophosphate Synthase Gene and RNA Interference of Cycloartenol Synthase Gene in Panax notoginseng Cells.
abstract: To conform to the multiple regulations of triterpene biosynthesis, the gene encoding farnesyl pyrophosphate synthase (FPS) was transformed intoPanax notoginseng(P. notoginseng) cells in which RNA interference (RNAi) of the cycloartenol synthase (CAS) gene had been accomplished. Transgenic cell lines showed both higher expression levels ofFPSand lower expression levels ofCAScompared to the wild-type (WT) cells. In the triterpene and phytosterol analysis, transgenic cell lines provided a higher accumulation of total triterpene saponins, and a lower amount of phytosterols in comparison with the WT cells. Compared with the cells in which RNAi of theCASgene was achieved, the cells with simultaneously over-expressedFPSand silencedCASshowed higher triterpene contents. These results demonstrate that over-expression ofFPScan break the rate-limiting reaction catalyzed by FPS in the triterpene saponins biosynthetic pathway; and inhibition ofCASexpression can decrease the synthesis metabolic flux of the phytosterol branch. Thus, more precursors flow in the direction of triterpene synthesis, and ultimately promote the accumulation ofP. notoginsengsaponins. Meanwhile, silencing and over-expressing key enzyme genes simultaneously is more effective than just manipulating one gene in the regulation of saponin biosynthesis.
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China. yangyan3650199@163.com.|School of Biotechnology and Engineering, Dianxi Science and Technology Normal University, Lincang 677000, China. yangyan3650199@163.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China. zz@kmust.edu.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Ge
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China. zhengfanbj2008@163.com.
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China. dianaloveyou2006@163.com.
authors.forename: Diqiu
authors.initials: D
authors.lastname: Liu
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China. aqjingsheng@163.com.
authors.forename: Chaoyin
authors.initials: C
authors.lastname: Chen
mesh_terms: D053898:Biosynthetic Pathways; D015870:Gene Expression; D023061:Gene Order; D005822:Genetic Vectors / Q000235:genetics; D051228:Geranyltranstransferase / Q000235:genetics*; D019751:Intramolecular Transferases / Q000235:genetics*; D053723:Panax notoginseng / Q000235:genetics* / Q000378:metabolism*; D059828:Plant Cells; D034622:RNA Interference; D012503:Saponins / Q000096:biosynthesis*; D014315:Triterpenes / Q000378:metabolism*
chemical_list: D012503:Saponins; D014315:Triterpenes; D051228:Geranyltranstransferase; D019751:Intramolecular Transferases; C021923:cycloartenol synthase
keywords: Panax; RNA interference; cycloartenol synthase; farnesyl pyrophosphate synthase; over-expression; triterpene