title: Transcriptional Responses and Gentiopicroside Biosynthesis in Methyl Jasmonate-Treated Gentiana macrophylla Seedlings.
abstract: Gentiana macrophylla, a medicinal plant with significant pharmacological properties, contains the bioactive compound gentiopicroside. Methyl jasmonate (MeJA) is an effective elicitor for enhancing the production of such compounds. However, little is known about MeJA-mediated biosynthesis of gentiopicroside. We investigated this phenomenon as well as gene expression profiles to determine the molecular mechanisms for MeJA-mediated gentiopicroside biosynthesis and regulation in G. macrophylla. Our HPLC results showed that Gentiana macrophylla seedlings exposed to MeJA had significantly higher concentrations of gentiopicroside when compared with control plants. We used RNA sequencing to compare transcriptional profiles in seedlings treated for 5 d with either 0 μmol L-1 MeJA (C) or 250 μmol L-1 MeJA (M5) and detected differentially expressed genes (DEGs). In total, 77,482 unique sequences were obtained from approximately 34 million reads. Of these, 48,466 (57.46%) sequences were annotated based on BLASTs performed against public databases. We identified 5,206 DEGs between the C and M5 samples, including genes related to the α-lenolenic acid degradation pathway, JA signaling pathway, and gentiopicroside biosynthesis. Expression of numerous enzyme genes in the glycolysis pathway was significantly up-regulated. Many genes encoding transcription factors (e.g. ERF, bHLH, MYB, and WRKY) also responded to MeJA elicitation. Rapid acceleration of the glycolysis pathway that supplies precursors for IPP biosynthesis and up-regulates the expression of enzyme genes in that IPP pathway are probably most responsible for MeJA stimulation of gentiopicroside synthesis. Our qRT-PCR results showed that the expression profiles of 12 gentiopicroside biosynthesis genes were consistent with the RNA-Seq data. These results increase our understanding about how the gentiopicroside biosynthesis pathway in G. macrophylla responds to MeJA.
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Cao
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Guo
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Xinbing
authors.initials: X
authors.lastname: Yang
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Huaiqin
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Biological Science and Technology, Shaanxi XueQian Normal University, Xi'an, China.
authors.forename: Wenping
authors.initials: W
authors.lastname: Hua
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Yihan
authors.initials: Y
authors.lastname: He
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Jiefang
authors.initials: J
authors.lastname: Kang
authors.affiliation: Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.
authors.forename: Zhezhi
authors.initials: Z
authors.lastname: Wang
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D053898:Biosynthetic Pathways / Q000187:drug effects / Q000235:genetics*; D003517:Cyclopentanes / Q000378:metabolism / Q000494:pharmacology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D030012:Gentiana / Q000187:drug effects / Q000235:genetics*; D006019:Glycolysis / Q000187:drug effects; D057888:Iridoid Glucosides / Q000378:metabolism*; D058977:Molecular Sequence Annotation; D054883:Oxylipins / Q000378:metabolism / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D015203:Reproducibility of Results; D064210:Secondary Metabolism / Q000187:drug effects / Q000235:genetics; D036226:Seedlings / Q000187:drug effects / Q000235:genetics*; D017423:Sequence Analysis, RNA; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects*; D059467:Transcriptome; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D017962:alpha-Linolenic Acid / Q000378:metabolism
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D057888:Iridoid Glucosides; D054883:Oxylipins; D014157:Transcription Factors; D017962:alpha-Linolenic Acid; C012997:gentiopicroside; C011006:jasmonic acid; C072239:methyl jasmonate