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Sun L, Yin J, Wang L, Li J, Hu C, Liu B, Zheng C, Chen J, Fotopoulos V, Shu Q, Jiang M. Role of serotonin in plant stress responses: Quo vadis? JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2025. [PMID: 40098453 DOI: 10.1111/jipb.13882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2024] [Accepted: 02/16/2025] [Indexed: 03/19/2025]
Abstract
Serotonin (5-hydroxytryptamine (5-HT)) is a pineal hormone and a secondary metabolite related to various hormonal and physiological functions at the organ, tissue, and cellular levels. It is considered increasingly important in regulating animal behavior, but the function of serotonin in plants is far less known. According to recent research, serotonin is vital for plant growth, development, and stress responses, achieved through transcriptional and phytohormonal interplay. Specifically, this review addresses critical gaps in the understanding of serotonin's function in plants by examining its biosynthesis, metabolism, and its multifaceted role in mitigating both abiotic stresses (salinity, drought, heat, cold, and heavy metals) as well as biotic challenges (pathogens, pests, and herbivores). As a pivotal player, it engages in a variety of significant cellular and molecular interactions, including those with reactive oxygen and nitrogen species (RONS), and various phytohormones such as auxin, abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), ethylene (ET), and cytokinin (CK). Advances in serotonin-related research are anticipated to offer a valuable basis for uncovering the regulatory pathways by which serotonin impacts the resilience of crops against abiotic stress.
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Affiliation(s)
- Like Sun
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Jiaxi Yin
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Long Wang
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Jingjing Li
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Can Hu
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Bo Liu
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Chenfan Zheng
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Jiale Chen
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Vasileios Fotopoulos
- Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, Lemesos, 3603, Cyprus
| | - Qingyao Shu
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
| | - Meng Jiang
- Hainan Institute, Zhejiang University, Yazhou Bay Science and Technology City, Sanya, 572025, China
- National Key Laboratory of Rice Biology and Breeding, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, The Advanced Seed Institute, Zhejiang University, Hangzhou, 310058, China
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Spiering MJ, Parsons JF, Eisenstein E. On the Biosynthesis of Bioactive Tryptamines in Black Cohosh ( Actaea racemosa L.). PLANTS (BASEL, SWITZERLAND) 2025; 14:292. [PMID: 39861645 PMCID: PMC11768127 DOI: 10.3390/plants14020292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2024] [Revised: 01/10/2025] [Accepted: 01/12/2025] [Indexed: 01/27/2025]
Abstract
Botanical dietary supplements are widely used, but issues of authenticity, consistency, safety, and efficacy that complicate their poorly understood mechanism of action have prompted questions and concerns in the popular and scientific literature. Black cohosh (Actaea racemosa L., syn. Cimicifuga racemosa, Nutt., Ranunculaceae) is a multicomponent botanical therapeutic used as a popular remedy for menopause and dysmenorrhea and explored as a treatment in breast and prostate cancer. However, its use and safety are controversial. A. racemosa tissues contain the bioactive serotonin analog N-methylserotonin, which is thought to contribute to the serotonergic activities of black cohosh-containing preparations. A. racemosa has several TDC-like genes hypothesized to encode tryptophan decarboxylases (TDCs) converting L-tryptophan to tryptamine, a direct serotonin precursor in plants. Expression of black cohosh TDC1, TDC2, and TDC3 in Saccharomyces cerevisiae resulted in the production of tryptamine. TDC1 and TDC3 had approximately fourfold higher activity than TDC2, which was attributable to a variable Cys/Ser active site residue identified by site-directed mutagenesis. Co-expression in yeast of the high-activity black cohosh TDCs with the next enzyme in serotonin biosynthesis, tryptamine 5-hydroxylase (T5H), from rice (Oryza sativa) resulted in the production of serotonin, whereas co-expression with low-activity TDCs did not, suggesting that TDC activity is a rate-limiting step in serotonin biosynthesis. Two T5H-like sequences were identified in A. racemose, but their co-expression with the high-activity TDCs in yeast did not result in serotonin production. TDC expression was detected in several black cohosh tissues, and phytochemical analysis using LC-MS revealed several new tryptamines, including tryptamine and serotonin, along with N-methylserotonin and, interestingly, N-N-dimethyl-5-hydroxytryptamine (bufotenine), which may contribute to hepatotoxicity. Incubation of A. racemosa leaves with tryptamine and N-methyltryptamine resulted in increased concentrations of serotonin and N-methylserotonin, respectively, suggesting that methylation of tryptamine precedes hydroxylation in the biosynthesis of N-methylserotonin. This work indicates a significantly greater variety of serotonin derivatives in A. racemosa than previously reported. Moreover, the activities of the TDCs underscore their key role in the production of serotonergic compounds in A. racemosa. Finally, it is proposed that tryptamine is first methylated and then hydroxylated to form the black cohosh signature compound N-methylserotonin.
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Affiliation(s)
- Martin J. Spiering
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
| | - James F. Parsons
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
| | - Edward Eisenstein
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
- Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
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3
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Erland LA. Views and perspectives on the indoleamines serotonin and melatonin in plants: past, present and future. PLANT SIGNALING & BEHAVIOR 2024; 19:2366545. [PMID: 38899558 PMCID: PMC11195476 DOI: 10.1080/15592324.2024.2366545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 06/05/2024] [Indexed: 06/21/2024]
Abstract
In the decades since their discovery in plants in the mid-to-late 1900s, melatonin (N-acetyl-5-methoxytryptamine) and serotonin (5-methoxytryptamine) have been established as their own class of phytohormone and have become popular targets for examination and study as stress ameliorating compounds. The indoleamines play roles across the plant life cycle from reproduction to morphogenesis and plant environmental perception. There is growing interest in harnessing the power of these plant neurotransmitters in applied and agricultural settings, particularly as we face increasingly volatile climates for food production; however, there is still a lot to learn about the mechanisms of indoleamine action in plants. A recent explosion of interest in these compounds has led to exponential growth in the field of melatonin research in particular. This concept paper aims to summarize the current status of indoleamine research and highlight some emerging trends.
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Malakar P, Gupta SK, Chattopadhyay D. Role of plant neurotransmitters in salt stress: A critical review. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2024; 211:108601. [PMID: 38696867 DOI: 10.1016/j.plaphy.2024.108601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 03/22/2024] [Accepted: 04/03/2024] [Indexed: 05/04/2024]
Abstract
Neurotransmitters are naturally found in many plants, but the molecular processes that govern their actions still need to be better understood. Acetylcholine, γ-Aminobutyric acid, histamine, melatonin, serotonin, and glutamate are the most common neurotransmitters in animals, and they all play a part in the development and information processing. It is worth noting that all these chemicals have been found in plants. Although much emphasis has been placed on understanding how neurotransmitters regulate mood and behaviour in humans, little is known about how they regulate plant growth and development. In this article, the information was reviewed and updated considering current thinking on neurotransmitter signaling in plants' metabolism, growth, development, salt tolerance, and the associated avenues for underlying research. The goal of this study is to advance neurotransmitter signaling research in plant biology, especially in the area of salt stress physiology.
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Affiliation(s)
- Paheli Malakar
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India.
| | - Santosh K Gupta
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India.
| | - Debasis Chattopadhyay
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India.
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Mishra V, Sarkar AK. Serotonin: A frontline player in plant growth and stress responses. PHYSIOLOGIA PLANTARUM 2023; 175:e13968. [PMID: 37402164 DOI: 10.1111/ppl.13968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 06/20/2023] [Indexed: 07/06/2023]
Abstract
Serotonin is a well-studied pineal hormone that functions as a neurotransmitter in mammals and is found in varying amounts in diverse plant species. By modulating gene and phytohormonal crosstalk, serotonin has a significant role in plant growth and stress response, including root, shoot, flowering, morphogenesis, and adaptability responses to numerous environmental signals. Despite its prevalence and importance in plant growth and development, its molecular action, regulation and signalling processes remain unknown. Here, we highlight the current knowledge of the role of serotonin-mediated regulation of plant growth and stress response. We focus on serotonin and its regulatory connections with phytohormonal crosstalk and address their possible functions in coordinating diverse phytohormonal responses during distinct developmental phases, correlating with melatonin. Additionally, we have also discussed the possible role of microRNAs (miRNAs) in the regulation of serotonin biosynthesis. In summary, serotonin may act as a node molecule to coordinate the balance between plant growth and stress response, which may shed light on finding its key regulatory pathways for uncovering its mysterious molecular network.
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Affiliation(s)
- Vishnu Mishra
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Ananda K Sarkar
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
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6
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Rosignoli S, Cosenza F, Moscou MJ, Civolani L, Musiani F, Forestan C, Milner SG, Savojardo C, Tuberosa R, Salvi S. Cloning the barley nec3 disease lesion mimic mutant using complementation by sequencing. THE PLANT GENOME 2022; 15:e20187. [PMID: 35302294 DOI: 10.1002/tpg2.20187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/17/2021] [Indexed: 06/14/2023]
Abstract
Disease lesion mimic (DLM) or necrotic mutants display necrotic lesions in the absence of pathogen infections. They can show improved resistance to some pathogens and their molecular dissection can contribute to revealing components of plant defense pathways. Although forward-genetics strategies to find genes causal to mutant phenotypes are available in crops, these strategies require the production of experimental cross populations, mutagenesis, or gene editing and are time- and resource-consuming or may have to deal with regulated plant materials. In this study, we described a collection of 34 DLM mutants in barley (Hordeum vulgare L.) and applied a novel method called complementation by sequencing (CBS), which enables the identification of the gene responsible for a mutant phenotype given the availability of two or more chemically mutagenized individuals showing the same phenotype. Complementation by sequencing relies on the feasibility to obtain all induced mutations present in chemical mutants and on the low probability that different individuals share the same mutated genes. By CBS, we identified a cytochrome P450 CYP71P1 gene as responsible for orange blotch DLM mutants, including the historical barley nec3 locus. By comparative phylogenetic analysis we showed that CYP71P1 gene family emerged early in angiosperm evolution but has been recurrently lost in some lineages including Arabidopsis thaliana (L.) Heynh. Complementation by sequencing is a straightforward cost-effective approach to clone genes controlling phenotypes in a chemically mutagenized collection. The TILLMore (TM) collection will be instrumental for understanding the molecular basis of DLM phenotypes and to contribute knowledge about mechanisms of host-pathogen interaction.
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Affiliation(s)
- Serena Rosignoli
- Dep. of Agricultural and Food Sciences, Univ. of Bologna, Viale G. Fanin 44, Bologna, Italy, 40127
| | - Francesco Cosenza
- Dep. of Agricultural and Food Sciences, Univ. of Bologna, Viale G. Fanin 44, Bologna, Italy, 40127
- The Sainsbury Laboratory, Univ. of East Anglia, Norwich Research Park, Norwich, NR4 7UK, UK
| | - Matthew J Moscou
- The Sainsbury Laboratory, Univ. of East Anglia, Norwich Research Park, Norwich, NR4 7UK, UK
| | - Laura Civolani
- Dep. of Agricultural and Food Sciences, Univ. of Bologna, Viale G. Fanin 44, Bologna, Italy, 40127
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry, Dep. of Pharmacy and Biotechnology, Univ. of Bologna, Via Belmeloro 6, Bologna, Italy, 40126
| | - Cristian Forestan
- Dep. of Agricultural and Food Sciences, Univ. of Bologna, Viale G. Fanin 44, Bologna, Italy, 40127
| | - Sara Giulia Milner
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Seeland, D
| | - Castrense Savojardo
- Biocomputing Group, Dep. of Pharmacy and Biotechnology, Univ. of Bologna, Via Belmeloro 6, Bologna, Italy, 40126
| | - Roberto Tuberosa
- Dep. of Agricultural and Food Sciences, Univ. of Bologna, Viale G. Fanin 44, Bologna, Italy, 40127
| | - Silvio Salvi
- Dep. of Agricultural and Food Sciences, Univ. of Bologna, Viale G. Fanin 44, Bologna, Italy, 40127
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Li Q, Jia E, Yan Y, Ma R, Dong J, Ma P. Using the Strategy of Inducing and Genetically Transforming Plant Suspension Cells to Produce High Value-Added Bioactive Substances. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:699-710. [PMID: 35018771 DOI: 10.1021/acs.jafc.1c05712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Plants can produce many functional bioactive substances. The suspension cell system of plants can be constructed based on its characteristics to realize the large-scale production of valuable products. In this review, we mainly talk about the main strategies, elicitation, and genetic transformation to improve the yield of active substances by using this system. Meanwhile, we focus on the challenges hiding in the practical application and the future prospects and provide new ideas and the theoretical basis for obtaining numerous bioactive substances from plants.
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Affiliation(s)
- Qian Li
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Entong Jia
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Yurong Yan
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Rui Ma
- Jilin Provincial Key Laboratory of Agricultural Biotechnology, Jilin Academy of Agricultural Sciences, Changchun, Jilin 130033, People's Republic of China
| | - Juane Dong
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
| | - Pengda Ma
- College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, People's Republic of China
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Negri S, Commisso M, Avesani L, Guzzo F. The case of tryptamine and serotonin in plants: a mysterious precursor for an illustrious metabolite. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:5336-5355. [PMID: 34009335 DOI: 10.1093/jxb/erab220] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
Indolamines are tryptophan-derived specialized metabolites belonging to the huge and ubiquitous indole alkaloids group. Serotonin and melatonin are the best-characterized members of this family, given their many hormonal and physiological roles in animals. Following their discovery in plants, the study of plant indolamines has flourished and their involvement in important processes, including stress responses, growth and development, and reproduction, has been proposed, leading to their classification as a new category of phytohormones. However, the complex indolamine puzzle is far from resolved, particularly the biological roles of tryptamine, the early serotonin precursor representing the central hub of many downstream indole alkaloids. Tryptophan decarboxylase, which catalyzes the synthesis of tryptamine, strictly regulates the flux of carbon and nitrogen from the tryptophan pool into the indolamine pathway. Furthermore, tryptamine accumulates to high levels in the reproductive organs of many plant species and therefore cannot be classed as a mere intermediate but rather as an end product with potentially important functions in fruits and seeds. This review summarizes current knowledge on the role of tryptamine and its close relative serotonin, emphasizing the need for a clear understanding of the functions of, and mutual relations between, these indolamines and their biosynthesis pathways in plants.
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Affiliation(s)
- Stefano Negri
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
| | - Mauro Commisso
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
| | - Linda Avesani
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
| | - Flavia Guzzo
- Department of Biotechnology, University of Verona, Strada Le Grazie, Verona, Italy
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Back K. Melatonin metabolism, signaling and possible roles in plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:376-391. [PMID: 32645752 DOI: 10.1111/tpj.14915] [Citation(s) in RCA: 129] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 06/15/2020] [Accepted: 06/24/2020] [Indexed: 05/20/2023]
Abstract
Melatonin is a multifunctional biomolecule found in both animals and plants. In this review, the biosynthesis, levels, signaling, and possible roles of melatonin and its metabolites in plants is summarized. Tryptamine 5-hydroxylase (T5H), which catalyzes the conversion of tryptamine into serotonin, has been proposed as a target to create a melatonin knockout mutant presenting a lesion-mimic phenotype in rice. With a reduced anabolic capacity for melatonin biosynthesis and an increased catabolic capacity for melatonin metabolism, all plants generally maintain low melatonin levels. Some plants, including Arabidopsis and Nicotiana tabacum (tobacco), do not possess tryptophan decarboxylase (TDC), the first committed step enzyme required for melatonin biosynthesis. Major melatonin metabolites include cyclic 3-hydroxymelatonin (3-OHM) and 2-hydroxymelatonin (2-OHM). Other melatonin metabolites such as N1 -acetyl-N2 -formyl-5-methoxykynuramine (AFMK), N-acetyl-5-methoxykynuramine (AMK) and 5-methoxytryptamine (5-MT) are also produced when melatonin is applied to Oryza sativa (rice). The signaling pathways of melatonin and its metabolites act via the mitogen-activated protein kinase (MAPK) cascade, possibly with Cand2 acting as a melatonin receptor, although the integrity of Cand2 remains controversial. Melatonin mediates many important functions in growth stimulation and stress tolerance through its potent antioxidant activity and function in activating the MAPK cascade. The concentration distribution of melatonin metabolites appears to be species specific because corresponding enzymes such as M2H, M3H, catalases, indoleamine 2,3-dioxygenase (IDO) and N-acetylserotonin deacetylase (ASDAC) are differentially expressed among plant species and even among different tissues within species. Differential levels of melatonin and its metabolites can lead to differential physiological effects among plants when melatonin is either applied exogenously or overproduced through ectopic overexpression.
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Affiliation(s)
- Kyoungwhan Back
- Department of Biotechnology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61186, Republic of Korea
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10
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Hairy root culture technology: applications, constraints and prospect. Appl Microbiol Biotechnol 2020; 105:35-53. [PMID: 33226470 DOI: 10.1007/s00253-020-11017-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/04/2020] [Accepted: 11/09/2020] [Indexed: 12/18/2022]
Abstract
Hairy root (HR) culture, a successful biotechnology combining in vitro tissue culture with recombinant DNA machinery, is intended for the genetic improvement of plants. This technology has been put to use since the last three decades for genetic advancement of medicinal and aromatic plants and also to harvest the economical products in the form of secondary metabolites that are significantly important for their ethnobotanical and pharmacological properties. It also provides an efficient way out for the quicker extraction and quantification of the valuable phytochemicals. The current review provides an account of the in vitro HR culture technology and its wide-scale applications in the field of research as well as in pharmaceutical industries. Different facets of HR with respect to the culture establishment, phytochemical production as well as research investigations concerning the areas of gene manipulation, biotransformation of the secondary metabolites, phytoremediation, their industrial utilisations and different problems encountered during the application of this technology have been covered in this appraisal. Eventually, an idea has been provided on HR about the recent trends on the progress of this technology that may open up newer prospects in near future and calls for further research and explorations in this field. KEY POINTS: • Genetic engineering-based HR culture aims towards enhanced secondary metabolite production. • This review explores an insight in the HR technology and its multi-faceted approaches. • Up-to-date ground-breaking research applications and constraints of HR culture are discussed.
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Erland LAE, Saxena P. Auxin driven indoleamine biosynthesis and the role of tryptophan as an inductive signal in Hypericum perforatum (L.). PLoS One 2019; 14:e0223878. [PMID: 31622392 PMCID: PMC6797091 DOI: 10.1371/journal.pone.0223878] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 10/01/2019] [Indexed: 11/19/2022] Open
Abstract
In the 60 years since Skoog and Miller first reported the chemical redirection of plant growth the underlying biochemical mechanisms are still poorly understood, with one challenge being the capacity for applied growth regulators to act indirectly or be metabolized to active phytohormones. We hypothesized that tryptophan is metabolized to auxin, melatonin or serotonin inducing organogenesis in St. John's wort (Hypericum perforatum L.). Root explants from two germplasm lines of St. John's wort with altered melatonin metabolism and wildtype were incubated with auxin or tryptophan for 24, 48 or 72 h to induce regeneration. In wildtype, tryptophan had little effect on the indoleamine pathway, and was found to promote primary growth, suggesting excess tryptophan moved quickly through various secondary metabolite pathways and protein synthesis. In lines 4 and 112 tryptophan was associated with modified morphogenesis, indoleamine and auxin levels. Incubation with tryptophan increased shoot organogenesis while incubation with auxin led to root regeneration. The established paradigm of thought views tryptophan primarily as a precursor for auxin and indoleamines, among other metabolites, and mediation of auxin action by the indoleamines as a one-way interaction. We propose that these processes run in both directions with auxin modifying indoleamine biosynthesis and the melatonin:serotonin balance contributing to its effects on plant morphogenesis, and that tryptophan also functions as an inductive signal to mediate diverse phytochemical and morphogenetic pathways.
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Affiliation(s)
- Lauren A. E. Erland
- Department of Plant Agriculture, Gosling Research Institute for Plant Preservation, University of Guelph, Guelph, Ontario, Canada
| | - Praveen Saxena
- Department of Plant Agriculture, Gosling Research Institute for Plant Preservation, University of Guelph, Guelph, Ontario, Canada
- * E-mail:
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Huang Q, Li L, Zheng M, Chen F, Long H, Deng G, Pan Z, Liang J, Li Q, Yu M, Zhang H. The Tryptophan decarboxylase 1 Gene From Aegilops variabilis No.1 Regulate the Resistance Against Cereal Cyst Nematode by Altering the Downstream Secondary Metabolite Contents Rather Than Auxin Synthesis. FRONTIERS IN PLANT SCIENCE 2018; 9:1297. [PMID: 30233630 PMCID: PMC6132075 DOI: 10.3389/fpls.2018.01297] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 08/17/2018] [Indexed: 05/24/2023]
Abstract
Cereal cyst nematode (CCN, Heterodera avenae) is a most important pathogen of wheat and causes tremendous yield loss annually over the world. Since the lack of resistance materials among wheat cultivars, identification and characterization of the resistance-related genes from the relatives of wheat is a necessary and efficient way. As a close relative of wheat with high resistance against CCN, Aegilops variabilis No.1 is believed to be a valuable source for wheat breeding against this devastating disease. However so far, very few resistance-associated genes have been characterized from this species. In this study, we present that the tryptophan decarboxylase genes from Ae. variabilis No.1 (AeVTDC1 and AeVTDC2) were both induced by CCN juveniles at the early stage of resistance response (30 h post-inoculation), with AeVTDC1 more sensitive to CCN infection than AeVTDC2. Silencing of AeVTDC1 led to compromised immunity to CCN with more CCN intrusion into roots; while overexpression AeVTDC1 in Nicotiana tabacum dramatically enhanced the resistance of plants by reducing the knots formed on roots. Metabolism analysis showed that the contents of secondary metabolites with activity of resistance to varied pathogens correlated with the expression level of AeVTDC1 in both Ae. variabilis No.1 and the transgenic tobacco plants. In addition, the content of IAA was not affected by either silencing or overexpressing of AeVTDC1. Hence, our research provided AeVTDC1 a valuable target that mediates resistance to CCN and root knot nematode (RKN, Meloidogyne naasi) without influencing the auxin biosynthesis.
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Affiliation(s)
- Qiulan Huang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- College of Life Sciences, Sichuan University, Chengdu, China
- University of the Chinese Academy of Sciences, Beijing, China
| | - Lin Li
- School of Basic Medical Sciences, Zunyi Medical University, Zunyi, China
| | - Minghui Zheng
- School of Basic Medical Sciences, Zunyi Medical University, Zunyi, China
| | - Fang Chen
- College of Life Sciences, Sichuan University, Chengdu, China
| | - Hai Long
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Guangbing Deng
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Zhifen Pan
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Junjun Liang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Qiao Li
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Maoqun Yu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
| | - Haili Zhang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
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Back K, Tan DX, Reiter RJ. Melatonin biosynthesis in plants: multiple pathways catalyze tryptophan to melatonin in the cytoplasm or chloroplasts. J Pineal Res 2016; 61:426-437. [PMID: 27600803 DOI: 10.1111/jpi.12364] [Citation(s) in RCA: 281] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 09/02/2016] [Indexed: 02/06/2023]
Abstract
Melatonin is an animal hormone as well as a signaling molecule in plants. It was first identified in plants in 1995, and almost all enzymes responsible for melatonin biosynthesis had already been characterized in these species. Melatonin biosynthesis from tryptophan requires four-step reactions. However, six genes, that is, TDC, TPH, T5H, SNAT, ASMT, and COMT, have been implicated in the synthesis of melatonin in plants, suggesting the presence of multiple pathways. Two major pathways have been proposed based on the enzyme kinetics: One is the tryptophan/tryptamine/serotonin/N-acetylserotonin/melatonin pathway, which may occur under normal growth conditions; the other is the tryptophan/tryptamine/serotonin/5-methoxytryptamine/melatonin pathway, which may occur when plants produce large amounts of serotonin, for example, upon senescence. The melatonin biosynthetic capacity associated with conversion of tryptophan to serotonin is much higher than that associated with conversion of serotonin to melatonin, which yields a low level of melatonin synthesis in plants. Many melatonin intermediates are produced in various subcellular compartments, such as the cytoplasm, endoplasmic reticulum, and chloroplasts, which either facilitates or impedes the subsequent enzymatic steps. Depending on the pathways, the final subcellular sites of melatonin synthesis vary at either the cytoplasm or chloroplasts, which may differentially affect the mode of action of melatonin in plants.
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Affiliation(s)
- Kyoungwhan Back
- Department of Biotechnology, Bioenergy Research Center, Chonnam National University, Gwangju, Korea.
| | - Dun-Xian Tan
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
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Erland LAE, Turi CE, Saxena PK. Serotonin: An ancient molecule and an important regulator of plant processes. Biotechnol Adv 2016; 34:1347-1361. [PMID: 27742596 DOI: 10.1016/j.biotechadv.2016.10.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 10/07/2016] [Accepted: 10/09/2016] [Indexed: 02/07/2023]
Abstract
Serotonin is an ancient indoleamine that was presumably part of the life cycle of the first prokaryotic life forms on Earth millions of years ago where it functioned as a powerful antioxidant to combat the increasingly oxygen rich atmosphere. First identified as a neurotransmitter signaling molecule in mammals, it is ubiquitous across all forms of life. Serotonin was discovered in plants many years after its discovery in mammals; however, it has now been confirmed in almost all plant families, where it plays important roles in plant growth and development, including functions in energy acquisition, seasonal cycles, modulation of reproductive development, control of root and shoot organogenesis, maintenance of plant tissues, delay of senescence, and responses to biotic and abiotic stresses. Despite its widespread presence and activity, there are many questions which remain unanswered about the role of serotonin in plants including the mode of signaling and receptor identity as well as the mechanisms of action of this important molecule. This review provides an overview of the role of serotonin in plant life and their ability to adapt.
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Affiliation(s)
- Lauren A E Erland
- Gosling Research Institute for Plant Preservation, Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Ontario N1G 2W1, Canada
| | - Christina E Turi
- Gosling Research Institute for Plant Preservation, Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Ontario N1G 2W1, Canada
| | - Praveen K Saxena
- Gosling Research Institute for Plant Preservation, Department of Plant Agriculture, University of Guelph, 50 Stone Road E, Guelph, Ontario N1G 2W1, Canada.
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Ludwig-Müller J, Jahn L, Lippert A, Püschel J, Walter A. Improvement of hairy root cultures and plants by changing biosynthetic pathways leading to pharmaceutical metabolites: strategies and applications. Biotechnol Adv 2014; 32:1168-79. [PMID: 24699436 DOI: 10.1016/j.biotechadv.2014.03.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 03/17/2014] [Accepted: 03/24/2014] [Indexed: 12/20/2022]
Abstract
A plethora of bioactive plant metabolites has been explored for pharmaceutical, food chemistry and agricultural applications. The chemical synthesis of these structures is often difficult, so plants are favorably used as producers. While whole plants can serve as a source for secondary metabolites and can be also improved by metabolic engineering, more often cell or organ cultures of relevant plant species are of interest. It should be noted that only in few cases the production for commercial application in such cultures has been achieved. Their genetic manipulation is sometimes faster and the production of a specific metabolite is more reliable, because of less environmental influences. In addition, upscaling in bioreactors is nowadays possible for many of these cultures, so some are already used in industry. There are approaches to alter the profile of metabolites not only by using plant genes, but also by using bacterial genes encoding modifying enzymes. Also, strategies to cope with unwanted or even toxic compounds are available. The need for metabolic engineering of plant secondary metabolite pathways is increasing with the rising demand for (novel) compounds with new bioactive properties. Here, we give some examples of recent developments for the metabolic engineering of plants and organ cultures, which can be used in the production of metabolites with interesting properties.
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Affiliation(s)
- Jutta Ludwig-Müller
- Technische Universität Dresden, Institut für Botanik, 01062 Dresden, Germany.
| | - Linda Jahn
- Technische Universität Dresden, Institut für Botanik, 01062 Dresden, Germany
| | - Annemarie Lippert
- Technische Universität Dresden, Institut für Botanik, 01062 Dresden, Germany
| | - Joachim Püschel
- Technische Universität Dresden, Institut für Botanik, 01062 Dresden, Germany
| | - Antje Walter
- Technische Universität Dresden, Institut für Botanik, 01062 Dresden, Germany
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16
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Vuković R, Bauer N, Curković-Perica M. Genetic elicitation by inducible expression of β-cryptogein stimulates secretion of phenolics from Coleus blumei hairy roots. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2013; 199-200:18-28. [PMID: 23265315 DOI: 10.1016/j.plantsci.2012.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2012] [Revised: 10/27/2012] [Accepted: 10/31/2012] [Indexed: 06/01/2023]
Abstract
The accumulation of phenolic compounds in plants is often part of the defense response against stress and pathogen attack, which can be triggered and activated by elicitors. Oomycetal proteinaceous elicitor, β-cryptogein, induces hypersensitive response and systemic acquired resistance against some pathogens. In order to test the effect of endogenously synthesized cryptogein protein on phenolic compounds accumulation in tissue, and secretion into the culture medium, Coleus blumei hairy roots were generated. Agrobacterium rhizogenes was employed to insert synthetic crypt gene, encoding β-cryptogein, under the control of alcohol-inducible promoter. The expression of β-cryptogein, in C. blumei hairy roots, was controlled by application of 1% and 2% ethanol, during 21 days induction period. Ethanol-induced expression of β-cryptogein caused significant decrease of soluble phenolics and rosmarinic acid (RA) in hairy root lines and increase of phenolics, RA and caffeic acid in culture medium. These data suggest that β-cryptogein might be a potential regulatory factor for phenolics secretion from the roots.
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Affiliation(s)
- Rosemary Vuković
- Department of Biology, J.J. Strossmayer University of Osijek, Osijek, Croatia
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Kanjanaphachoat P, Wei BY, Lo SF, Wang IW, Wang CS, Yu SM, Yen ML, Chiu SH, Lai CC, Chen LJ. Serotonin accumulation in transgenic rice by over-expressing tryptophan decarboxylase results in a dark brown phenotype and stunted growth. PLANT MOLECULAR BIOLOGY 2012; 78:525-43. [PMID: 22297847 DOI: 10.1007/s11103-012-9882-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Accepted: 01/03/2012] [Indexed: 05/08/2023]
Abstract
A mutant M47286 with a stunted growth, low fertility and dark-brown phenotype was identified from a T-DNA-tagged rice mutant library. This mutant contained a copy of the T-DNA tag inserted at the location where the expression of two putative tryptophan decarboxylase genes, TDC-1 and TDC-3, were activated. Enzymatic assays of both recombinant proteins showed tryptophan decarboxylase activities that converted tryptophan to tryptamine, which could be converted to serotonin by a constitutively expressed tryptamine 5' hydroxylase (T5H) in rice plants. Over-expression of TDC-1 and TDC-3 in transgenic rice recapitulated the stunted growth, darkbrown phenotype and resulted in a low fertility similar to M47286. The degree of stunted growth and dark-brown color was proportional to the expression levels of TDC-1 and TDC-3. The levels of tryptamine and serotonin accumulation in these transgenic rice lines were also directly correlated with the expression levels of TDC-1 and TDC-3. A mass spectrometry assay demonstrated that the darkbrown leaves and hulls in the TDC-overexpressing transgenic rice were caused by the accumulation of serotonin dimer and that the stunted growth and low fertility were also caused by the accumulation of serotonin and serotonin dimer, but not tryptamine. These results represent the first evidence that over-expression of TDC results in stunted growth, low fertility and the accumulation of serotonin, which when converted to serotonin dimer, leads to a dark brown plant color.
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Rostampour S, Hashemi Sohi H, Jourabchi E, Ansari E. Influence of Agrobacterium rhizogenes on induction of hairy roots and benzylisoquinoline alkaloids production in Persian poppy (Papaver bracteatum Lindl.): preliminary report. World J Microbiol Biotechnol 2009. [DOI: 10.1007/s11274-009-0081-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Ishihara A, Hashimoto Y, Tanaka C, Dubouzet JG, Nakao T, Matsuda F, Nishioka T, Miyagawa H, Wakasa K. The tryptophan pathway is involved in the defense responses of rice against pathogenic infection via serotonin production. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 54:481-95. [PMID: 18266919 DOI: 10.1111/j.1365-313x.2008.03441.x] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The upregulation of the tryptophan (Trp) pathway in rice leaves infected by Bipolaris oryzae was indicated by: (i) enhanced enzyme activity of anthranilate synthase (AS), which regulates metabolic flux in the Trp pathway; (ii) elevated levels of the AS (OASA2, OASB1, and OASB2) transcripts; and (iii) increases in the contents of anthranilate, indole, and Trp. The measurement of the contents of Trp-derived metabolites by high-performance liquid chromatography coupled with tandem mass spectrometry revealed that serotonin and its hydroxycinnamic acid amides were accumulated in infected leaves. Serotonin accumulation was preceded by a transient increase in the tryptamine content and by marked activation of Trp decarboxylase, indicating that enhanced Trp production is linked to the formation of serotonin from Trp via tryptamine. Feeding of radiolabeled serotonin to inoculated leaves demonstrated that serotonin is incorporated into the cell walls of lesion tissue. The leaves of a propagating-type lesion mimic mutant (sl, Sekiguchi lesion) lacked both serotonin production and deposition of unextractable brown material at the infection sites, and showed increased susceptibility to B. oryzae infection. Treating the mutant with serotonin restored deposition of brown material at the lesion site. In addition, the serotonin treatment suppressed the growth of fungal hyphae in the leaf tissues of the sl mutant. These findings indicated that the activation of the Trp pathway is involved in the establishment of effective physical defenses by producing serotonin in rice leaves.
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Affiliation(s)
- Atsushi Ishihara
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
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21
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Kang S, Kang K, Lee K, Back K. Characterization of rice tryptophan decarboxylases and their direct involvement in serotonin biosynthesis in transgenic rice. PLANTA 2007; 227:263-72. [PMID: 17763868 DOI: 10.1007/s00425-007-0614-z] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Accepted: 08/15/2007] [Indexed: 05/17/2023]
Abstract
L-Tryptophan decarboxylase (TDC) and L-tyrosine decarboxylase (TYDC) belong to a family of aromatic L-amino acid decarboxylases and catalyze the conversion of tryptophan and tyrosine into tryptamine and tyramine, respectively. The rice genome has been shown to contain seven TDC or TYDC-like genes. Three of these genes for which cDNA clones were available were characterized to assign their functions using heterologous expression in Escherichia coli and rice (Oryza sativa cv. Dongjin). The purified products of two of the genes were expressed in E. coli and exhibited TDC activity, whereas the remaining gene could not be expressed in E. coli. The recombinant TDC protein with the greatest TDC activity showed a K (m) of 0.69 mM for tryptophan, and its activity was not inhibited by phenylalanine or tyrosine, indicating a high level of substrate specificity toward tryptophan. The ectopic expression of the three cDNA clones in rice led to the abundant production of the products of the encoded enzymes, tyramine and tryptamine. The overproduction of TYDC resulted in stunted growth and a lack of seed production due to tyramine accumulation, which increased as the plant aged. In contrast, transgenic plants that produced TDC showed a normal phenotype and contained 25-fold and 11-fold higher serotonin in the leaves and seeds, respectively, than the wild-type plants. The overproduction of either tyramine or serotonin was not strongly related to the enhanced synthesis of tyramine or serotonin derivatives, such as feruloyltyramine and feruloylserotonin, which are secondary metabolites that act as phytoalexins in plants.
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Affiliation(s)
- Sei Kang
- Department of Molecular Biotechnology, Agricultural Plant Stress Research Center, Biotechnology Research Institute, Chonnam National University, Gwangju, South Korea
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22
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Gómez-Galera S, Pelacho AM, Gené A, Capell T, Christou P. The genetic manipulation of medicinal and aromatic plants. PLANT CELL REPORTS 2007; 26:1689-715. [PMID: 17609957 DOI: 10.1007/s00299-007-0384-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Revised: 05/04/2007] [Accepted: 05/11/2007] [Indexed: 05/16/2023]
Abstract
Medicinal and aromatic plants have always been intimately linked with human health and culture. Plant-derived medicines constitute a substantial component of present day human healthcare systems in industrialized as well as developing countries. They are products of plant secondary metabolism and are involved in many other aspects of a plant's interaction with its immediate environment. The genetic manipulation of plants together with the establishment of in vitro plant regeneration systems facilitates efforts to engineer secondary product metabolic pathways. Advances in the cloning of genes involved in relevant pathways, the development of high throughput screening systems for chemical and biological activity, genomics tools and resources, and the recognition of a higher order of regulation of secondary plant metabolism operating at the whole plant level facilitate strategies for the effective manipulation of secondary products in plants. Here, we discuss advances in engineering metabolic pathways for specific classes of compounds in medicinal and aromatic plants and we identify remaining constraints and future prospects in the field. In particular we focus on indole, tropane, nicotine, isoquinoline alcaloids, monoterpenoids such as menthol and related compounds, diterpenoids such as taxol, sequiterpenoids such as artemisinin and aromatic amino acids.
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Affiliation(s)
- Sonia Gómez-Galera
- Departament de Producció Vegetal i Ciència Forestal, Universitat de Lleida, Av. Alcalde Rovira Roure, 191, 25198, Lleida, Spain
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Facchini PJ. Regulation of alkaloid biosynthesis in plants. THE ALKALOIDS. CHEMISTRY AND BIOLOGY 2007; 63:1-44. [PMID: 17133713 DOI: 10.1016/s1099-4831(06)63001-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Affiliation(s)
- Peter J Facchini
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
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Pasquali G, Porto DD, Fett-Neto AG. Metabolic engineering of cell cultures versus whole plant complexity in production of bioactive monoterpene indole alkaloids: Recent progress related to old dilemma. J Biosci Bioeng 2006; 101:287-96. [PMID: 16716935 DOI: 10.1263/jbb.101.287] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Accepted: 11/12/2005] [Indexed: 11/17/2022]
Abstract
Monoterpene indole alkaloids (MIAs) are a large class of plant alkaloids with significant pharmacological interest. The sustained production of MIAs at high yields is an important goal in biotechnology. Intensive effort has been expended toward the isolation, cloning, characterization and transgenic modulation of genes involved in MIA biosynthesis and in the control of the expression of these biosynthesis-related genes. At the same time, considerable progress has been made in the detailed description of the subcellular-, cellular-, tissue- and organ-specific expressions of portions of the biosynthetic pathways leading to the production of MIAs, revealing a complex picture of the transport of biosynthetic intermediates among membrane compartments, cells and tissues. The identification of the particular environmental and ontogenetic requirements for maximum alkaloid yield in MIA-producing plants has been useful in improving the supply of bioactive molecules. The search for new bioactive MIAs, particularly in tropical and subtropical regions, is continuously increasing the arsenal for therapeutic, industrially and agriculturally useful molecules. In this review we focus on recent progress in the production of MIAs in transgenic cell cultures and organs (with emphasis on Catharanthus roseus and Rauvolfia serpentina alkaloids), advances in the understanding of in planta spatial-temporal expression of MIA metabolic pathways, and on the identification of factors capable of modulating bioactive alkaloid accumulation in nontransgenic differentiated cultures and plants (with emphasis on new MIAs from Psychotria species). The combined use of metabolic engineering and physiological modulation in transgenic and wild-type plants, although not fully exploited to date, is likely to provide the sustainable and rational supply of bioactive MIAs needed for human well being.
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Affiliation(s)
- Giancarlo Pasquali
- Programa de Pós-graduação em Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, Pr. 43.431, P.O. Box 15.005, CEP 91.501-970, Porto Alegre, RS, Brazil
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Hong SB, Peebles CAM, Shanks JV, San KY, Gibson SI. Expression of the Arabidopsis feedback-insensitive anthranilate synthase holoenzyme and tryptophan decarboxylase genes in Catharanthus roseus hairy roots. J Biotechnol 2006; 122:28-38. [PMID: 16188339 DOI: 10.1016/j.jbiotec.2005.08.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2005] [Revised: 07/28/2005] [Accepted: 08/05/2005] [Indexed: 11/17/2022]
Abstract
In plants, the indole pathway provides precursors for a variety of secondary metabolites. In Catharanthus roseus, a decarboxylated derivative of tryptophan, tryptamine, is a building block for the biosynthesis of terpenoid indole alkaloids. Previously, we manipulated the indole pathway by introducing an Arabidopsis feedback-insensitive anthranilate synthase (AS) alpha subunit (trp5) cDNA and C. roseus tryptophan decarboxylase gene (TDC) under the control of a glucocorticoid-inducible promoter into C. roseus hairy roots [Hughes, E.H., Hong, S.-B., Gibson, S.I., Shanks, J.V., San, K.-Y. 2004a. Expression of a feedback-resistant anthranilate synthase in Catharanthus roseus hairy roots provides evidence for tight regulation of terpenoid indole alkaloid levels. Biotechnol. Bioeng. 86, 718-727; Hughes, E.H., Hong, S.-B., Gibson, S.I., Shanks, J.V., San, K.-Y. 2004b. Metabolic engineering of the indole pathway in Catharanthus roseus hairy roots and increased accumulation of tryptamine and serpentine. Metabol. Eng. 6, 268-276]. Inducible expression of either or both transgenes did not lead to significant increases in overall alkaloid levels despite the considerable accumulation of tryptophan and tryptamine. In an attempt to more successfully engineer the indole pathway, a wild type Arabidopsis ASbeta subunit (ASB1) cDNA was constitutively expressed along with the inducible expression of trp5 and TDC in C. roseus hairy roots. Transgenic hairy roots expressing both trp5 and ASB1 show a significantly greater resistance to feedback inhibition of AS activity by tryptophan than plants expressing only trp5. In fact, a 4.5-fold higher concentration of tryptophan is required to achieve 50% inhibition of AS activity in plants overexpressing both genes than in plants expressing only trp5. In addition, upon a 3 day induction during the exponential phase, a trp5:ASB1 hairy root line produced 1.8 times more tryptophan (specific yield ca. 3.0 mg g(-1) dry weight) than the trp5 hairy root line. Concurrently, tryptamine levels increase up to 9-fold in the induced trp5:ASB1 line (specific yield ca. 1.9 mg g(-1) dry weight) as compared with only a 4-fold tryptamine increase in the induced trp5 line (specific yield ca. 0.3 mg g(-1) dry weight). However, endogenous TDC activities of both trp5:ASB1 and trp5 lines remain unchanged irrespective of induction. When TDC is ectopically expressed together with trp5 and ASB1, the induced trp5:ASB1:TDC hairy root line accumulates tryptamine up to 14-fold higher than the uninduced line. In parallel with the remarkable accumulation of tryptamine upon induction, alkaloid accumulation levels were significantly changed depending on the duration and dosage of induction.
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Affiliation(s)
- Seung-Beom Hong
- Department of Biochemistry and Cell Biology, MS-140, Rice University, Houston, TX 77005, USA
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26
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Di Fiore S, Li Q, Leech MJ, Schuster F, Emans N, Fischer R, Schillberg S. Targeting tryptophan decarboxylase to selected subcellular compartments of tobacco plants affects enzyme stability and in vivo function and leads to a lesion-mimic phenotype. PLANT PHYSIOLOGY 2002; 129:1160-9. [PMID: 12114570 PMCID: PMC166510 DOI: 10.1104/pp.010889] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2001] [Revised: 03/06/2002] [Accepted: 04/08/2002] [Indexed: 05/18/2023]
Abstract
Tryptophan decarboxylase (TDC) is a cytosolic enzyme that catalyzes an early step of the terpenoid indole alkaloid biosynthetic pathway by decarboxylation of L-tryptophan to produce the protoalkaloid tryptamine. In the present study, recombinant TDC was targeted to the chloroplast, cytosol, and endoplasmic reticulum (ER) of tobacco (Nicotiana tabacum) plants to evaluate the effects of subcellular compartmentation on the accumulation of functional enzyme and its corresponding enzymatic product. TDC accumulation and in vivo function was significantly affected by the subcellular localization. Immunoblot analysis demonstrated that chloroplast-targeted TDC had improved accumulation and/or stability when compared with the cytosolic enzyme. Because ER-targeted TDC was not detectable by immunoblot analysis and tryptamine levels found in transient expression studies and in transgenic plants were low, it was concluded that the recombinant TDC was most likely unstable if ER retained. Targeting TDC to the chloroplast stroma resulted in the highest accumulation level of tryptamine so far reported in the literature for studies on heterologous TDC expression in tobacco. However, plants accumulating high levels of functional TDC in the chloroplast developed a lesion-mimic phenotype that was probably triggered by the relatively high accumulation of tryptamine in this compartment. We demonstrate that subcellular targeting may provide a useful strategy for enhancing accumulation and/or stability of enzymes involved in secondary metabolism and to divert metabolic flux toward desired end products. However, metabolic engineering of plants is a very demanding task because unexpected, and possibly unwanted, effects may be observed on plant metabolism and/or phenotype.
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Affiliation(s)
- Stefano Di Fiore
- Institut für Molekulare Biotechnologie (Biologie VII) Rheinisch-Westfälische Technische Hochschule Aachen, 52074 Aachen, Germany
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Abstract
Alkaloids purified from plants provide many pharmacologically active compounds, including leading chemotherapy drugs. As is generally true of secondary metabolites, overall productivity is low, making commercial production expensive. Alternative production methods remain impractical, leaving the plant as the best source for these valuable chemicals. Recently, significant progress in characterizing the biosynthetic pathways leading to various alkaloids has been made, and a number of relevant genes have been cloned. Metabolic engineering employing such genes provides a promising technology for improved productivity in plant cell cultures, plant tissue cultures, or intact plants. In exploring solutions though, metabolic engineers must be careful to recognize the limitations inherent in designing plant systems.
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Affiliation(s)
- Erik H Hughes
- Department of Chemical Engineering, Rice University, Houston, Texas 77030, USA
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Facchini PJ. ALKALOID BIOSYNTHESIS IN PLANTS: Biochemistry, Cell Biology, Molecular Regulation, and Metabolic Engineering Applications. ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY 2001; 52:29-66. [PMID: 11337391 DOI: 10.1146/annurev.arplant.52.1.29] [Citation(s) in RCA: 288] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent advances in the cell, developmental, and molecular biology of alkaloid biosynthesis have heightened our appreciation for the complexity and importance of plant secondary pathways. Several biosynthetic genes involved in the formation of tropane, benzylisoquinoline, and terpenoid indole alkaloids have now been isolated. The early events of signal perception, the pathways of signal transduction, and the function of gene promoters have been studied in relation to the regulation of alkaloid metabolism. Enzymes involved in alkaloid biosynthesis are associated with diverse subcellular compartments including the cytosol, vacuole, tonoplast membrane, endoplasmic reticulum, chloroplast stroma, thylakoid membranes, and perhaps unique "biosynthetic" or transport vesicles. Localization studies have shown that sequential alkaloid biosynthetic enzymes can also occur in distinct cell types, suggesting the intercellular transport of pathway intermediates. Isolated genes have also been used to genetically alter the accumulation of specific alkaloids and other plant secondary metabolites. Metabolic modifications include increased indole alkaloid levels, altered tropane alkaloid accumulation, elevated serotonin synthesis, reduced indole glucosinolate production, redirected shikimate metabolism, and increased cell wall-bound tyramine formation. This review discusses the biochemistry, cell biology, molecular regulation, and metabolic engineering of alkaloid biosynthesis in plants.
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Affiliation(s)
- Peter J Facchini
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada; e-mail:
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Facchini PJ, Huber-Allanach KL, Tari LW. Plant aromatic L-amino acid decarboxylases: evolution, biochemistry, regulation, and metabolic engineering applications. PHYTOCHEMISTRY 2000; 54:121-38. [PMID: 10872203 DOI: 10.1016/s0031-9422(00)00050-9] [Citation(s) in RCA: 176] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A comprehensive survey of the extensive literature relevant to the evolution, physiology, biochemistry, regulation, and genetic engineering applications of plant aromatic L-amino acid decarboxylases (AADCs) is presented. AADCs catalyze the pyridoxal-5'-phosphate (PLP)-dependent decarboxylation of select aromatic L-amino acids in plants, mammals, and insects. Two plant AADCs, L-tryptophan decarboxylase (TDC) and L-tyrosine decarboxylase (TYDC), have attracted considerable attention because of their role in the biosynthesis of pharmaceutically important monoterpenoid indole alkaloids and benzylisoquinoline alkaloids, respectively. Although plant and animal AADCs share extensive amino acid homology, the enzymes display striking differences in their substrate specificities. AADCs from mammals and insects accept a broad range of aromatic L-amino acids, whereas TDC and TYDC from plants exhibit exclusive substrate specificity for L-amino acids with either indole or phenol side chains, but not both. Recent biochemical and kinetic studies on animal AADCs support basic features of the classic AADC reaction mechanism. The catalytic mechanism involves the formation of a Schiff base between PLP and an invariable lysine residue, followed by a transaldimination reaction with an aromatic L-amino acid substrate. Both TDC and TYDC are primarily regulated at the transcriptional level by developmental and environmental factors. However, the putative post-translational regulation of TDC via the ubiquitin pathway, by an ATP-dependent proteolytic process, has also been suggested. Isolated TDC and TYDC genes have been used to genetically alter the regulation of secondary metabolic pathways derived from aromatic amino acids in several plant species. The metabolic modifications include increased serotonin levels, reduced indole glucosinolate levels, redirected shikimate metabolism, increased indole alkaloid levels, and increased cell wall-bound tyramine levels.
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Affiliation(s)
- P J Facchini
- Department of Biological Sciences, University of Calgary, Alta., Canada.
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Abstract
Agrobacterium rhizogenes causes hairy root disease in plants. The neoplastic roots produced by A. rhizogenes infection is characterized by high growth rate and genetic stability. These genetically transformed root cultures can produce higher levels of secondary metabolites or amounts comparable to that of intact plants. Hairy root cultures offer promise for production of valuable secondary metabolites in many plants. The main constraint for commercial exploitation of hairy root cultures is their scaling up, as there is a need for developing a specially designed bioreactor that permits the growth of interconnected tissues unevenly distributed throughout the vessel. Rheological characteristics of heterogeneous system should also be taken into consideration during mass scale culturing of hairy roots. Development of bioreactor models for hairy root cultures is still a recent phenomenon. It is also necessary to develop computer-aided models for different parameters such as oxygen consumption and excretion of product to the medium. Further, transformed roots are able to regenerate genetically stable plants as transgenics or clones. This property of rapid growth and high plantlet regeneration frequency allows clonal propagation of elite plants. In addition, the altered phenotype of hairy root regenerants (hairy root syndrome) is useful in plant breeding programs with plants of ornamental interest. In vitro transformation and regeneration from hairy roots facilitates application of biotechnology to tree species. The ability to manipulate trees at a cellular and molecular level shows great potential for clonal propagation and genetic improvement. Transgenic root system offers tremendous potential for introducing additional genes along with the Ri T-DNA genes for alteration of metabolic pathways and production of useful metabolites or compounds of interest. This article discusses various applications and perspectives of hairy root cultures and the recent progress achieved with respect to transformation of plants using A. rhizogenes.
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Affiliation(s)
- A Giri
- School of Biotechnology, Jawaharlal Nehru Technological University, Hyderabad 500028, India
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Abstract
Plant cell cultures are being widely used in scientific studies on the physiology, biochemistry and molecular biology of primary and secondary metabolism, developmental regulation and cellular responses to pathogens and stress. In this chapter the significance of plant cell cultures in biotechnology is discussed with special emphasis on commercial production of secondary metabolites and pharmaceuticals, the potential of genetically transformed cell cultures, photosynthetically active cell cultures, production of somatic embryos, and novel assay systems based on the use of plant cells. Future aspects of biotechnical applications with respect to the potentials and limitations of these approaches are assessed, particularly in comparison with the productivity of lower eucaryotes.
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Affiliation(s)
- H P Mühlbach
- Department of Genetics, University of Hamburg, Germany.
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Chapter 12 Plant Biotechnology and the Production of Alkaloids: Prospects of Metabolic Engineering. THE ALKALOIDS: CHEMISTRY AND BIOLOGY 1998. [DOI: 10.1016/s1099-4831(08)60050-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Verpoorte R, van der Heijden R, Moreno PR. Chapter 3 Biosynthesis of Terpenoid Indole Alkaloids in Catharanthus roseus Cells. THE ALKALOIDS: CHEMISTRY AND PHARMACOLOGY 1997. [DOI: 10.1016/s0099-9598(08)60017-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Herminghaus S, Tholl D, Rügenhagen C, Fecker LF, Leuschner C, Berlin J. Improved metabolic action of a bacterial lysine decarboxylase gene in tobacco hairy root cultures by its fusion to a rbcS transit peptide coding sequence. Transgenic Res 1996; 5:193-201. [PMID: 8673147 DOI: 10.1007/bf01969709] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The gene of a bacterial lysine decarboxylase (ldc) fused to a rbcS transit peptide coding sequence (tp), and under the control of the CaMV 35S promoter, was expressed in hairy root cultures of Nicotiana tabacum. The fusion of the ldc to the targeting signal sequence improved the performance of the bacterial gene in the plant cells in many respects. Nearly all transgenic hairy root cultures harbouring the 35S-tp-ldc gene contained distinctly higher lysine decarboxylase activity (from 1.5 to 30 pkat LDC per mg protein) than those which had been transformed with constructs in which the gene had been directly cloned behind the CaMV 35S promoter. The higher enzyme activity led to the accumulation of up to 0.7% cadaverine on a dry mass basis. In addition, part of the cadaverine pool was used for increased biosynthesis of anabasine, an alkaloid which was hardly detectable in control cultures. The best line contained anabasine levels of 0.5% dry mass, which could be further be enhanced by feeding of lysine.
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Affiliation(s)
- S Herminghaus
- Gesellschaft f. Biotechnologische Forschung m.b.H., Braunschweig, Germany
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Goddijn OJ, Pennings EJ, van der Helm P, Schilperoort RA, Verpoorte R, Hoge JH. Overexpression of a tryptophan decarboxylase cDNA in Catharanthus roseus crown gall calluses results in increased tryptamine levels but not in increased terpenoid indole alkaloid production. Transgenic Res 1995; 4:315-23. [PMID: 8589734 DOI: 10.1007/bf01972528] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The enzyme tryptophan decarboxylase (TDC) (EC 4.1.1.28) catalyses a key step in the biosynthesis of terpenoid indole alkaloids in C. roseus by converting tryptophan into tryptamine. Hardly any tdc mRNA could be detected in hormone-independent callus and cell suspension cultures transformed by the oncogenic T-DNA of Agrobacterium tumefaciens. Supply of tryptamine may therefore represent a limiting factor in the biosynthesis of alkaloids by such cultures. To investigate this possibility, chimaeric gene constructs, in which a tdc cDNA is linked in the sense or antisense orientation to the cauliflower mosaic virus 35S promoter and terminator, were introduced in C. roseus cells by infecting seedlings with an oncogenic A. tumefaciens strain. In the resulting crown gall tumour calluses harbouring the tdc sense construct, an increased TDC protein level, TDC activity and tryptamine content but no significant increase in terpenoid indole alkaloid production were observed compared to empty-vector-transformed tumour calluses. In tumour calluses containing the tdc antisense construct, decreased levels of TDC activity were measured. Factors which might be responsible for the lack in increased terpenoid indole alkaloid production in the tdc cDNA overexpressing crown gall calluses are discussed.
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Affiliation(s)
- O J Goddijn
- Institute of Molecular Plant Sciences, Leiden University, Clusius Laboratory, Netherlands
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Poulsen C, Goddijn OJM, Hoge JHC, Verpoorte R. Anthranilate synthase and chorismate mutase activities in transgenic tobacco plants overexpressing tryptophan decarboxylase fromCatharanthus roseus. Transgenic Res 1994. [DOI: 10.1007/bf01976026] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Fecker LF, Rügenhagen C, Berlin J. Increased production of cadaverine and anabasine in hairy root cultures of Nicotiana tabacum expressing a bacterial lysine decarboxylase gene. PLANT MOLECULAR BIOLOGY 1993; 23:11-21. [PMID: 8219043 DOI: 10.1007/bf00021415] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Several hairy root cultures of Nicotiana tabacum varieties, carrying two direct repeats of a bacterial lysine decarboxylase (ldc) gene controlled by the cauliflower mosaic virus (CaMV) 35S promoter expressed LDC activity up to 1 pkat/mg protein. Such activity was, for example, sufficient to increase cadaverine levels of the best line SR3/1-K1,2 from ca. 50 micrograms (control cultures) to about 700 micrograms/g dry mass. Some of the overproduced cadaverine of this line was used for the formation of anabasine, as shown by a 3-fold increase of this alkaloid. In transgenic lines with lower LDC activity the changes of cadaverine and anabasine levels were correspondingly lower and sometimes hardly distinguishable from controls. Feeding of lysine to root cultures, even to those with low LDC activity, greatly enhanced cadaverine and anabasine levels, while the amino acid had no or very little effect on controls and LDC-negative lines.
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Affiliation(s)
- L F Fecker
- Institut für Biochemie und Pflanzenvirologie, Biologische Bundesanstalt für Land- und Forstwirtschaft, Braunschweig, Germany
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