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Yamunarani R, Ramegowda V, Senthil-Kumar M, Mysore KS. High-Throughput Analysis of Gene Function under Multiple Abiotic Stresses Using Leaf Disks from Silenced Plants. Methods Mol Biol 2022; 2408:181-189. [PMID: 35325423 DOI: 10.1007/978-1-0716-1875-2_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The high throughputness and affordability of "omics" technologies is leading to the identification of a large number of abiotic stress genes, with many of them responsive to multiple stresses. In vivo functional characterization of these genes under multiple stresses is challenging but essential to develop resilient crops for the changing climate. Here we describe a high-throughput Virus-Induced Gene Silencing-based methodology for functional analysis of genes under multiple abiotic stresses using leaf disks. Leaves with maximal silencing, which is localized to only a few leaves and to a short period, can be effectively used for multiple stress imposition and stress affect quantification.
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Affiliation(s)
- Ramegowda Yamunarani
- Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India
| | - Venkategowda Ramegowda
- Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
| | | | - Kirankumar S Mysore
- Institute for Agricultural Biosciences, Oklahoma State University, Ardmore, OK, USA
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Liu Q, Xu K, Yi L, Hou Y, Li D, Hu H, Zhou F, Song P, Yu Y, Wei Q, Guan Y, Hu P, Bu R, Chen E, Su X, Li H, Li C. A rapid, simple, and highly efficient method for VIGS and in vitro-inoculation of plant virus by INABS applied to crops that develop axillary buds and can survive from cuttings. BMC PLANT BIOLOGY 2021; 21:545. [PMID: 34800968 PMCID: PMC8605592 DOI: 10.1186/s12870-021-03331-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Virus-induced gene silencing (VIGS) is one of the most convenient and powerful methods of reverse genetics. In vitro-inoculation of plant virus is an important method for studying the interactions between viruses and plants. Agrobacterium-based infiltration has been widely adopted as a tool for VIGS and in vitro-inoculation of plant virus. Most agrobacterium-based infiltration methods applied to VIGS and virus inoculation have the characteristics of low transformation efficiencies, long plant growth time, large amounts of plant tissue, large test spaces, and complex preparation procedures. Therefore, a rapid, simple, economical, and highly efficient VIGS and virus inoculation method is in need. Previous studies have shown that the selection of suitable plant tissues and inoculation sites is the key to successful infection. RESULTS In this study, Tobacco rattle virus (TRV) mediated VIGS and Tomato yellow leaf curl virus (TYLCV) for virus inoculation were developed in tomato plants based on the agrobacterium tumefaciens-based infiltration by injection of the no-apical-bud stem section (INABS). The no-apical-bud stem section had a "Y- type" asymmetric structure and contained an axillary bud that was about 1-3 cm in length. This protocol provides high transformation (56.7%) and inoculation efficiency (68.3%), which generates VIGS transformants or diseased plants in a very short period (8 dpi). Moreover, it greatly reduces the required experimental space. This method will facilitate functional genomic studies and large-scale disease resistance screening. CONCLUSIONS Overall, a rapid, simple, and highly efficient method for VIGS and virus inoculation by INABS was developed in tomato. It was reasonable to believe that it can be used as a reference for the other virus inoculation methods and for the application of VIGS to other crops (such as sweet potato, potato, cassava and tobacco) that develop axillary buds and can survive from cuttings.
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Affiliation(s)
- Qili Liu
- College of Plant Protection, Henan Agricultural University, Zhengzhou, 450002, China
- Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, 453001, China
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Kedong Xu
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou, 466000, China
| | - Lun Yi
- Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Yalin Hou
- Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Dongxiao Li
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Haiyan Hu
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Feng Zhou
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Puwen Song
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Yongang Yu
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Qichao Wei
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Yuanyuan Guan
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Ping Hu
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Ruifang Bu
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Eryong Chen
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Xiaojia Su
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China
| | - Honglian Li
- College of Plant Protection, Henan Agricultural University, Zhengzhou, 450002, China.
| | - Chengwei Li
- Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, 453001, China.
- Henan Engineering Research Center of Crop Genome Editing, Henan Institute of Science and Technology, Xinxiang, 453001, China.
- College of Biological Engineering, Henan University of Technology, Zhengzhou, 450001, China.
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Xiao Z, Xing M, Liu X, Fang Z, Yang L, Zhang Y, Wang Y, Zhuang M, Lv H. An efficient virus-induced gene silencing (VIGS) system for functional genomics in Brassicas using a cabbage leaf curl virus (CaLCuV)-based vector. PLANTA 2020; 252:42. [PMID: 32870402 DOI: 10.1007/s00425-020-03454-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
CaLCuV-based VIGS effectively works in cabbage and contributes to efficient functional genomics research in Brassica crop species. Virus-induced gene silencing (VIGS), a posttranscriptional gene silencing method, is an effective technique for analysing the functions of genes in plants. However, no VIGS vectors have been available for Brassica oleracea until now. Here, tobacco rattle virus (TRV), pTYs and cabbage leaf curl virus (CaLCuV) gene-silencing vectors (PCVA/PCVB) were chosen to improve the VIGS system in cabbage using the phytoene desaturase (PDS) gene as an efficient visual indicator of VIGS. We successfully silenced the expression of PDS and observed photobleaching phenomena in cabbage in response to pTYs and CaLCuV, with the latter being more easy to operate and less expensive. The parameters potentially affecting the silencing efficiency of VIGS by CaLCuV in cabbage, including the targeting fragment strategy, inoculation method and incubation temperature, were then compared. The optimized CaLCuV-based VIGS system involves the following: an approximately 500 bp insert sequence, an Agrobacterium OD600 of 1.0, use of the vacuum osmosis method applied at the bud stage, and an incubation temperature of 22 °C. Using these parameters, we achieved a stable silencing efficiency of 65%. To further test the effectiveness of the system, we selected the Mg-chelatase H subunit (ChlH) gene in cabbage and knocked down its expression, and we observed yellow leaves, as expected. We successfully applied the CaLCuV-based VIGS system to two other representative Brassica crop species, B. rapa and B. nigra, and thus expanded the application scope of this system. Our VIGS system described here will contribute to efficient functional genomics research in Brassica crop species.
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Affiliation(s)
- Zhiliang Xiao
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Miaomiao Xing
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Xing Liu
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Zhiyuan Fang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Limei Yang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Yangyong Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Yong Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China
| | - Mu Zhuang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China.
| | - Honghao Lv
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie Street, Beijing, 100081, China.
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Mdodana NT, Jewell JF, Phiri EE, Smith ML, Oberlander K, Mahmoodi S, Kossmann J, Lloyd JR. Mutations in Glucan, Water Dikinase Affect Starch Degradation and Gametophore Development in the Moss Physcomitrella patens. Sci Rep 2019; 9:15114. [PMID: 31641159 PMCID: PMC6805951 DOI: 10.1038/s41598-019-51632-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 10/01/2019] [Indexed: 11/23/2022] Open
Abstract
The role of starch degradation in non-vascular plants is poorly understood. To expand our knowledge of this area, we have studied this process in Physcomitrella patens. This has been achieved through examination of the step known to initiate starch degradation in angiosperms, glucan phosphorylation, catalysed by glucan, water dikinase (GWD) enzymes. Phylogenetic analysis indicates that GWD isoforms can be divided into two clades, one of which contains GWD1/GWD2 and the other GWD3 isoforms. These clades split at a very early stage within plant evolution, as distinct sequences that cluster within each were identified in all major plant lineages. Of the five genes we identified within the Physcomitrella genome that encode GWD-like enzymes, two group within the GWD1/GWD2 clade and the others within the GWD3 clade. Proteins encoded by both loci in the GWD1/GWD2 clade, named PpGWDa and PpGWDb, are localised in plastids. Mutations of either PpGWDa or PpGWDb reduce starch phosphate abundance, however, a mutation at the PpGWDa locus had a much greater influence than one at PpGWDb. Only mutations affecting PpGWDa inhibited starch degradation. Mutants lacking this enzyme also failed to develop gametophores, a phenotype that could be chemically complemented using glucose supplementation within the growth medium.
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Affiliation(s)
- Ntombizanele T Mdodana
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa
| | - Jonathan F Jewell
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa
| | - Ethel E Phiri
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa
| | - Marthinus L Smith
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa
| | - Kenneth Oberlander
- Schweickerdt Herbarium, Department of Plant and Soil Sciences, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa
| | - Saire Mahmoodi
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa
| | - Jens Kossmann
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa
| | - James R Lloyd
- Department of Genetics, Institute for Plant Biotechnology, University of Stellenbosch, Stellenbosch, South Africa.
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Zhang J, Yu D, Zhang Y, Liu K, Xu K, Zhang F, Wang J, Tan G, Nie X, Ji Q, Zhao L, Li C. Vacuum and Co-cultivation Agroinfiltration of (Germinated) Seeds Results in Tobacco Rattle Virus (TRV) Mediated Whole-Plant Virus-Induced Gene Silencing (VIGS) in Wheat and Maize. FRONTIERS IN PLANT SCIENCE 2017; 8:393. [PMID: 28382049 PMCID: PMC5360694 DOI: 10.3389/fpls.2017.00393] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/07/2017] [Indexed: 05/06/2023]
Abstract
Tobacco rattle virus (TRV)-mediated virus-induced gene silencing (VIGS) has been frequently used in dicots. Here we show that it can also be used in monocots, by presenting a system involving use of a novel infiltration solution (containing acetosyringone, cysteine, and Tween 20) that enables whole-plant level VIGS of (germinated) seeds in wheat and maize. Using the established system, phytoene desaturase (PDS) genes were successfully silenced, resulting in typical photo-bleaching symptoms in the leaves of treated wheat and maize. In addition, three wheat homoeoalleles of MLO, a key gene repressing defense responses to powdery mildew in wheat, were simultaneously silenced in susceptible wheat with this system, resulting in it becoming resistant to powdery mildew. The system has the advantages generally associated with TRV-mediated VIGS systems (e.g., high-efficiency, mild virus infection symptoms, and effectiveness in different organs). However, it also has the following further advantages: (germinated) seed-stage agroinfiltration; greater rapidity and convenience; whole-plant level gene silencing; adequately stable transformation; and suitability for studying functions of genes involved in seed germination and early plant development stages.
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Affiliation(s)
- Ju Zhang
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
| | - Deshui Yu
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
| | - Yi Zhang
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
- College of Agronomy, Henan Agricultural University, ZhengzhouChina
| | - Kun Liu
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
| | - Kedong Xu
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
| | - Fuli Zhang
- College of Life Science and Agronomy, Zhoukou Normal University, ZhoukouChina
| | - Jian Wang
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
| | - Guangxuan Tan
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
| | - Xianhui Nie
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
- College of Life Science and Agronomy, Zhoukou Normal University, ZhoukouChina
| | - Qiaohua Ji
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
- College of Life Science and Agronomy, Zhoukou Normal University, ZhoukouChina
| | - Lu Zhao
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
- College of Life Science and Agronomy, Zhoukou Normal University, ZhoukouChina
| | - Chengwei Li
- Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, ZhoukouChina
- Henan Key Laboratory of Crop Molecular Breeding and Bioreactor, ZhoukouChina
- College of Life Science and Technology, Henan Institute of Science and Technology, XinxiangChina
- *Correspondence: Chengwei Li,
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Zhirnov IV, Trifonova EA, Kochetov AV, Shumny VK. Virus-induced silencing as a method for studying gene functions in higher plants. RUSS J GENET+ 2015. [DOI: 10.1134/s1022795415050099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zheng LL, Qu LH. Application of microRNA gene resources in the improvement of agronomic traits in rice. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:329-36. [PMID: 25583449 DOI: 10.1111/pbi.12321] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/02/2014] [Accepted: 12/02/2014] [Indexed: 05/20/2023]
Abstract
microRNAs (miRNAs) are important nonprotein-coding genes that are involved in almost all biological processes, including cell differentiation and fate determination, developmental regulation, and immune responses. Investigations have shown that some miRNAs can highly affect plant agricultural traits, including virus resistance, nematode resistance, drought and salinity tolerance, heavy metal detoxification, biomass yield, grain yield, fruit development and flower development. Therefore, these miRNAs are considered a newly identified gene resource for the genetic improvement of crops. In this review, we will summarize the recent findings of the rice miRNA-directed regulatory network, which controls agronomic traits such as yield, quality and stress tolerance, and explore the outlook for the uses of these miRNA-associated traits in rice biotechnology.
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Affiliation(s)
- Ling-Ling Zheng
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, Sun Yat-sen University, Guangzhou, China
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George GM, Ruckle ME, Lloyd JR. Virus-induced gene silencing as a scalable tool to study drought tolerance in plants. Methods Mol Biol 2015; 1287:243-53. [PMID: 25740370 DOI: 10.1007/978-1-4939-2453-0_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Here we describe the methodology of using virus-induced gene silencing (VIGS) as a powerful and scalable tool to screen the function of genes that participate in adaptation to drought. Silencing of endogenous gene expression in Nicotiana benthamiana is achieved by systemic infection of the aerial parts of the plant with a virus engineered to contain homologous fragments of the target gene(s) of interest. Silenced plant material can be consistently produced with little optimization in less than 1 month without specialized equipment, using only simple cloning and transformation techniques. Although maximal silencing is localized to only a few leaves, when whole plants are subjected to water stress, the tissue from these silenced leaves can be characterized for physiological, biochemical, and transcriptional responses to determine the role of the candidate genes in drought tolerance.
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Affiliation(s)
- Gavin M George
- Department of Biology, ETH Zurich, Universitaetsstrasse 2, Zurich, CH-8092, Switzerland
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Desgagné-Penix I, Facchini PJ. Systematic silencing of benzylisoquinoline alkaloid biosynthetic genes reveals the major route to papaverine in opium poppy. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:331-44. [PMID: 22725256 DOI: 10.1111/j.1365-313x.2012.05084.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Papaverine, a major benzylisoquinoline alkaloid in opium poppy (Papaver somniferum), is used as a vasodilator and antispasmodic. Conversion of the initial intermediate (S)-norcoclaurine to papaverine involves 3'-hydroxylation, four O-methylations and dehydrogenation. However, our understanding of papaverine biosynthesis remains controversial more than a century after an initial scheme was proposed. In vitro assays and in vivo labeling studies have been insufficient to establish the sequence of conversions, the potential role of the intermediate (S)-reticuline, and the enzymes involved. We used virus-induced gene silencing in opium poppy to individually suppress the expression of six genes with putative roles in papaverine biosynthesis. Suppression of the gene encoding coclaurine N-methyltransferase dramatically increased papaverine levels at the expense of N-methylated alkaloids, indicating that the main biosynthetic route to papaverine proceeds via N-desmethylated compounds rather than through (S)-reticuline. Suppression of genes encoding (S)-3'-hydroxy-N-methylcoclaurine 4-O-methyltransferase and norreticuline 7-O-methyltransferase, which accept certain N-desmethylated alkaloids, reduced papaverine content. In contrast, suppression of genes encoding N-methylcoclaurine 3'-hydroxylase or reticuline 7-O-methyltransferase, which are specific for N-methylated alkaloids, did not affect papaverine levels. Suppression of norcoclaurine 6-O-methyltransferase transcript levels significantly suppressed total alkaloid accumulation, implicating (S)-coclaurine as a key branch-point intermediate. The differential detection of N-desmethylated compounds in response to suppression of specific genes highlights the primary route to papaverine.
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Affiliation(s)
- Isabel Desgagné-Penix
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada
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