title: Promoting scopolamine biosynthesis in transgenic Atropa belladonna plants with pmt and h6h overexpression under field conditions.
abstract: Atropa belladonna is one of the most important plant sources for producing pharmaceutical tropane alkaloids (TAs). T1 progeny of transgenic A. belladonna, in which putrescine N-methyltransferase (EC. 2.1.1.53) from Nicotiana tabacum (NtPMT) and hyoscyamine 6β-hydroxylase (EC. 1.14.11.14) from Hyoscyamus niger (HnH6H) were overexpressed, were established to investigate TA biosynthesis and distribution in ripe fruits, leaves, stems, primary roots and secondary roots under field conditions. Both NtPMT and HnH6H were detected at the transcriptional level in transgenic plants, whereas they were not detected in wild-type plants. The transgenes did not influence the root-specific expression patterns of endogenous TA biosynthetic genes in A. belladonna. All four endogenous TA biosynthetic genes (AbPMT, AbTRI, AbCYP80F1 and AbH6H) had the highest/exclusive expression levels in secondary roots, suggesting that TAs were mainly synthesized in secondary roots. T1 progeny of transgenic A. belladonna showed an impressive scopolamine-rich chemotype that greatly improved the pharmaceutical value of A. belladonna. The higher efficiency of hyoscyamine conversion was found in aerial than in underground parts. In aerial parts of transgenic plants, hyoscyamine was totally converted to downstream alkaloids, especially scopolamine. Hyoscyamine, anisodamine and scopolamine were detected in underground parts, but scopolamine and anisodamine were more abundant than hyoscyamine. The exclusively higher levels of anisodamine in roots suggested that it might be difficult for its translocation from root to aerial organs. T1 progeny of transgenic A. belladonna, which produces scopolamine at very high levels (2.94-5.13 mg g(-1)) in field conditions, can provide more valuable plant materials for scopolamine production.
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), SWU-TAAHC Medicinal Plant Joint R&D Center, School of Life Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Xia
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), SWU-TAAHC Medicinal Plant Joint R&D Center, School of Life Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), SWU-TAAHC Medicinal Plant Joint R&D Center, School of Life Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Qiaozhuo
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), SWU-TAAHC Medicinal Plant Joint R&D Center, School of Life Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Qiang
authors.affiliation: Institute of Entomology, The Provincial Key Laboratory for Plant Pest Management of Mountainous Region, Guizhou University, Guiyang, 550025, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Guo
authors.affiliation: TAAHC-SWU Medicinal Plant Joint R&D Center, Tibetan Collaborative Innovation Center of Agricultural and Animal Husbandry Resources, Agriculture and Animal Husbandry College, Tibet University, Nyingchi of Tibet, 860000, China.
authors.forename: Xiaozhong
authors.initials: X
authors.lastname: Lan
authors.affiliation: SWU-TAAHC Medicinal Plant Joint R&D Center, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.affiliation: Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), SWU-TAAHC Medicinal Plant Joint R&D Center, School of Life Sciences, Southwest University, Chongqing, 400715, China. Electronic address: zhliao@swu.edu.cn.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Liao
mesh_terms: D001532:Atropa belladonna / Q000235:genetics*; D053898:Biosynthetic Pathways / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D032304:Hyoscyamus / Q000201:enzymology*; D008780:Methyltransferases / Q000235:genetics* / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity / Q000235:genetics; D030821:Plants, Genetically Modified; D012601:Scopolamine / Q000737:chemistry / Q000378:metabolism*; D014026:Nicotiana / Q000201:enzymology*; D019076:Transgenes
chemical_list: D012601:Scopolamine; D006899:Mixed Function Oxygenases; C052273:hyoscyamine (6S)-dioxygenase; D008780:Methyltransferases; C112598:putrescine N-methyltransferase
keywords: Atropa belladonna; Hyoscyamine 6β-hydroxylase; Metabolic engineering; Putrescine N-methyltransferase; Tropane alkaloids