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Jadaun JS, Kushwaha AK, Sangwan NS, Narnoliya LK, Mishra S, Sangwan RS. WRKY1-mediated regulation of tryptophan decarboxylase in tryptamine generation for withanamide production in Withania somnifera (Ashwagandha). PLANT CELL REPORTS 2020; 39:1443-1465. [PMID: 32789542 DOI: 10.1007/s00299-020-02574-4] [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] [Received: 04/21/2020] [Revised: 07/14/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023]
Abstract
WsWRKY1-mediated transcriptional modulation of Withania somnifera tryptophan decarboxylase gene (WsTDC) helps to regulate fruit-specific tryptamine generation for production of withanamides. Withania somnifera is a highly valued medicinal plant. Recent demonstration of novel indolyl metabolites called withanamides in its fruits (berries) prompted us to investigate its tryptophan decarboxylase (TDC), as tryptophan is invariably a precursor for indole moiety. TDC catalyzes conversion of tryptophan into tryptamine, and the catalytic reaction constitutes a committed metabolic step for synthesis of an array of indolyl metabolites. The TDC gene (WsTDC) was cloned from berries of the plant and expressed in E. coli. The recombinant enzyme was purified and characterized for its catalytic attributes. Catalytic and structural aspects of the enzyme indicated its regulatory/rate-limiting significance in generation of the indolyl metabolites. Novel tissue-wise and developmentally differential abundance of WsTDC transcripts reflected its preeminent role in withanamide biogenesis in the fruits. Transgenic lines overexpressing WsTDC gene showed accumulation of tryptamine at significantly higher levels, while lines silenced for WsTDC exhibited considerably depleted levels of tryptamine. Cloning and sequence analysis of promoter of WsTDC revealed the presence of W-box in it. Follow-up studies on isolation of WsWRKY1 transcription factor and its overexpression in W. somnifera revealed that WsTDC expression was substantially induced by WsWRKY1 resulting in overproduction of tryptamine. The study invokes a key role of TDC in regulating the indolyl secondary metabolites through enabling elevated flux/supply of tryptamine at multiple levels from gene expression to catalytic attributes overall coordinated by WsWRKY1. This is the first biochemical, molecular, structural, physiological and regulatory description of a fruit-functional TDC.
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Affiliation(s)
- Jyoti Singh Jadaun
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), Lucknow, 226015, India
| | - Amit Kumar Kushwaha
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), Lucknow, 226015, India
| | - Neelam S Sangwan
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), Lucknow, 226015, India.
- Department of Biochemistry, Central University of Haryana, Mahendergarh, Haryana, 123031, India.
| | - Lokesh Kumar Narnoliya
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), Lucknow, 226015, India
| | - Smrati Mishra
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), Lucknow, 226015, India
| | - Rajender Singh Sangwan
- Department of Metabolic and Structural Biology, CSIR-Central Institute of Medicinal and Aromatic Plants (CSIR-CIMAP), Lucknow, 226015, India.
- Academy of Scientific and Innovative Research (AcSIR), CSIR-HRDC Campus, Sector 19, Kamla Nehru Nagar, Ghaziabad, Uttar Pradesh, 201002, India.
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Paul P, Singh SK, Patra B, Sui X, Pattanaik S, Yuan L. A differentially regulated AP2/ERF transcription factor gene cluster acts downstream of a MAP kinase cascade to modulate terpenoid indole alkaloid biosynthesis in Catharanthus roseus. THE NEW PHYTOLOGIST 2017; 213:1107-1123. [PMID: 27801944 DOI: 10.1111/nph.14252] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/03/2016] [Indexed: 05/23/2023]
Abstract
Catharanthus roseus produces bioactive terpenoid indole alkaloids (TIAs), including the chemotherapeutics, vincristine and vinblastine. Transcriptional regulation of TIA biosynthesis is not fully understood. The jasmonic acid (JA)-responsive AP2/ERF transcription factor (TF), ORCA3, and its regulator, CrMYC2, play key roles in TIA biosynthesis. ORCA3 forms a physical cluster with two uncharacterized AP2/ERFs, ORCA4 and 5. Here, we report that (1) the ORCA gene cluster is differentially regulated; (2) ORCA4, while overlapping functionally with ORCA3, modulates an additional set of TIA genes. Unlike ORCA3, ORCA4 overexpression resulted in dramatic increase of TIA accumulation in C. roseus hairy roots. In addition, CrMYC2 is capable of activating ORCA3 and co-regulating TIA pathway genes concomitantly with ORCA3. The ORCA gene cluster and CrMYC2 act downstream of a MAP kinase cascade that includes a previously uncharacterized MAP kinase kinase, CrMAPKK1. Overexpression of CrMAPKK1 in C. roseus hairy roots upregulated TIA pathways genes and increased TIA accumulation. This work provides detailed characterization of a TF gene cluster and advances our understanding of the transcriptional and post-translational regulatory mechanisms that govern TIA biosynthesis in C. roseus.
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Affiliation(s)
- Priyanka Paul
- Department of Plant and Soil Sciences and Kentucky Tobacco Research Development Center, University of Kentucky, 1401 University Drive, Lexington, KY, 40546, USA
| | - Sanjay K Singh
- Department of Plant and Soil Sciences and Kentucky Tobacco Research Development Center, University of Kentucky, 1401 University Drive, Lexington, KY, 40546, USA
| | - Barunava Patra
- Department of Plant and Soil Sciences and Kentucky Tobacco Research Development Center, University of Kentucky, 1401 University Drive, Lexington, KY, 40546, USA
| | - Xueyi Sui
- Department of Plant and Soil Sciences and Kentucky Tobacco Research Development Center, University of Kentucky, 1401 University Drive, Lexington, KY, 40546, USA
| | - Sitakanta Pattanaik
- Department of Plant and Soil Sciences and Kentucky Tobacco Research Development Center, University of Kentucky, 1401 University Drive, Lexington, KY, 40546, USA
| | - Ling Yuan
- Department of Plant and Soil Sciences and Kentucky Tobacco Research Development Center, University of Kentucky, 1401 University Drive, Lexington, KY, 40546, USA
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Mehrotra S, Goel MK, Srivastava V, Rahman LU. Hairy root biotechnology of Rauwolfia serpentina: a potent approach for the production of pharmaceutically important terpenoid indole alkaloids. Biotechnol Lett 2014; 37:253-63. [DOI: 10.1007/s10529-014-1695-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 10/03/2014] [Indexed: 12/19/2022]
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Yang Z, Patra B, Li R, Pattanaik S, Yuan L. Promoter analysis reveals cis-regulatory motifs associated with the expression of the WRKY transcription factor CrWRKY1 in Catharanthus roseus. PLANTA 2013; 238:1039-49. [PMID: 23979312 DOI: 10.1007/s00425-013-1949-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 08/14/2013] [Indexed: 06/02/2023]
Abstract
WRKY transcription factors (TFs) are emerging as an important group of regulators of plant secondary metabolism. However, the cis-regulatory elements associated with their regulation have not been well characterized. We have previously demonstrated that CrWRKY1, a member of subgroup III of the WRKY TF family, regulates biosynthesis of terpenoid indole alkaloids in the ornamental and medicinal plant, Catharanthus roseus. Here, we report the isolation and functional characterization of the CrWRKY1 promoter. In silico analysis of the promoter sequence reveals the presence of several potential TF binding motifs, indicating the involvement of additional TFs in the regulation of the TIA pathway. The CrWRKY1 promoter can drive the expression of a β-glucuronidase (GUS) reporter gene in native (C. roseus protoplasts and transgenic hairy roots) and heterologous (transgenic tobacco seedlings) systems. Analysis of 5'- or 3'-end deletions indicates that the sequence located between positions -140 to -93 bp and -3 to +113 bp, relative to the transcription start site, is critical for promoter activity. Mutation analysis shows that two overlapping as-1 elements and a CT-rich motif contribute significantly to promoter activity. The CrWRKY1 promoter is induced in response to methyl jasmonate (MJ) treatment and the promoter region between -230 and -93 bp contains a putative MJ-responsive element. The CrWRKY1 promoter can potentially be used as a tool to isolate novel TFs involved in the regulation of the TIA pathway.
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Affiliation(s)
- Zhirong Yang
- Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
- Department of Biochemistry, College of Arts and Sciences, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Barunava Patra
- Department of Plant and Soil Sciences, Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY, 40546, USA
| | - Runzhi Li
- Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Sitakanta Pattanaik
- Department of Plant and Soil Sciences, Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY, 40546, USA.
| | - Ling Yuan
- Department of Plant and Soil Sciences, Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY, 40546, USA.
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Yamada Y, Sato F. Transcription factors in alkaloid biosynthesis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 305:339-82. [PMID: 23890386 DOI: 10.1016/b978-0-12-407695-2.00008-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Higher plants produce a large variety of low-molecular weight secondary compounds. Among them, nitrogen-containing alkaloids are the most biologically active and are often used pharmaceutically. Whereas alkaloid chemistry has been intensively investigated, alkaloid biosynthesis, including the relevant biosynthetic enzymes, genes and their regulation, and especially transcription factors, is largely unknown, as only a limited number of plant species produce certain types of alkaloids and they are difficult to study. Recently, however, several groups have succeeded in isolating the transcription factors that are involved in the biosynthesis of several types of alkaloids, including bHLH, ERF, and WRKY. Most of them show Jasmonate (JA) responsiveness, which suggests that the JA signaling cascade plays an important role in alkaloid biosynthesis. Here, we summarize the types and functions of transcription factors that have been isolated in alkaloid biosynthesis, and characterize their similarities and differences compared to those in other secondary metabolite pathways, such as phenylpropanoid and terpenoid biosyntheses. The evolution of this biosynthetic pathway and regulatory network, as well as the application of these transcription factors to metabolic engineering, is discussed.
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Affiliation(s)
- Yasuyuki Yamada
- Department of Plant Gene and Totipotency, Graduate School of Biostudies, Kyoto University, Kitashirakawa, Sakyo, Kyoto, Japan
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Raina SK, Wankhede DP, Sinha AK. Catharanthus roseus mitogen-activated protein kinase 3 confers UV and heat tolerance to Saccharomyces cerevisiae. PLANT SIGNALING & BEHAVIOR 2013; 8:e22716. [PMID: 23221751 PMCID: PMC3745576 DOI: 10.4161/psb.22716] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 10/30/2012] [Indexed: 06/01/2023]
Abstract
Catharanthus roseus is an important source of pharmaceutically important Monoterpenoid Indole Alkaloids (MIAs). Accumulation of many of the MIAs is induced in response to abiotic stresses such as wound, ultra violet (UV) irradiations, etc. Recently, we have demonstrated a possible role of CrMPK3, a C. roseus mitogen-activated protein kinase in stress-induced accumulation of a few MIAs. Here, we extend our findings using Saccharomyces cerevisiae to investigate the role of CrMPK3 in giving tolerance to abiotic stresses. Yeast cells transformed with CrMPK3 was found to show enhanced tolerance to UV and heat stress. Comparison of CrMPK3 and SLT2, a MAPK from yeast shows high-sequence identity particularly at conserved domains. Additionally, heat stress is also shown to activate a 43 kDa MAP kinase, possibly CrMPK3 in C. roseus leaves. These findings indicate the role of CrMPK3 in stress-induced MIA accumulation as well as in stress tolerance.
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Characterization of variation and quantitative trait loci related to terpenoid indole alkaloid yield in a recombinant inbred line mapping population of Catharanthus roseus. J Genet 2012. [DOI: 10.1007/s12041-012-0150-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Verma P, Mathur AK, Srivastava A, Mathur A. Emerging trends in research on spatial and temporal organization of terpenoid indole alkaloid pathway in Catharanthus roseus: a literature update. PROTOPLASMA 2012; 249:255-68. [PMID: 0 DOI: 10.1007/s00709-011-0291-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 05/17/2011] [Indexed: 05/21/2023]
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Suttipanta N, Pattanaik S, Kulshrestha M, Patra B, Singh SK, Yuan L. The transcription factor CrWRKY1 positively regulates the terpenoid indole alkaloid biosynthesis in Catharanthus roseus. PLANT PHYSIOLOGY 2011; 157:2081-93. [PMID: 21988879 PMCID: PMC3327198 DOI: 10.1104/pp.111.181834] [Citation(s) in RCA: 242] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 10/06/2011] [Indexed: 05/18/2023]
Abstract
Catharanthus roseus produces a large array of terpenoid indole alkaloids (TIAs) that are an important source of natural or semisynthetic anticancer drugs. The biosynthesis of TIAs is tissue specific and induced by certain phytohormones and fungal elicitors, indicating the involvement of a complex transcriptional control network. However, the transcriptional regulation of the TIA pathway is poorly understood. Here, we describe a C. roseus WRKY transcription factor, CrWRKY1, that is preferentially expressed in roots and induced by the phytohormones jasmonate, gibberellic acid, and ethylene. The overexpression of CrWRKY1 in C. roseus hairy roots up-regulated several key TIA pathway genes, especially Tryptophan Decarboxylase (TDC), as well as the transcriptional repressors ZCT1 (for zinc-finger C. roseus transcription factor 1), ZCT2, and ZCT3. However, CrWRKY1 overexpression repressed the transcriptional activators ORCA2, ORCA3, and CrMYC2. Overexpression of a dominant-repressive form of CrWRKY1, created by fusing the SRDX repressor domain to CrWRKY1, resulted in the down-regulation of TDC and ZCTs but the up-regulation of ORCA3 and CrMYC2. CrWRKY1 bound to the W box elements of the TDC promoter in electrophoretic mobility shift, yeast one-hybrid, and C. roseus protoplast assays. Up-regulation of TDC increased TDC activity, tryptamine concentration, and resistance to 4-methyl tryptophan inhibition of CrWRKY1 hairy roots. Compared with control roots, CrWRKY1 hairy roots accumulated up to 3-fold higher levels of serpentine. The preferential expression of CrWRKY1 in roots and its interaction with transcription factors including ORCA3, CrMYC2, and ZCTs may play a key role in determining the root-specific accumulation of serpentine in C. roseus plants.
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10
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Spiering MJ, Urban LA, Nuss DL, Gopalan V, Stoltzfus A, Eisenstein E. Gene identification in black cohosh (Actaea racemosa L.): expressed sequence tag profiling and genetic screening yields candidate genes for production of bioactive secondary metabolites. PLANT CELL REPORTS 2011; 30:613-629. [PMID: 21188383 DOI: 10.1007/s00299-010-0979-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 11/30/2010] [Accepted: 12/08/2010] [Indexed: 05/30/2023]
Abstract
Black cohosh (Actaea racemosa L., syn. Cimicifuga racemosa, Nutt., Ranunculaceae) is a popular herb used for relieving menopausal discomforts. A variety of secondary metabolites, including triterpenoids, phenolic dimers, and serotonin derivatives have been associated with its biological activity, but the genes and metabolic pathways as well as the tissue distribution of their production in this plant are unknown. A gene discovery effort was initiated in A. racemosa by partial sequencing of cDNA libraries constructed from young leaf, rhizome, and root tissues. In total, 2,066 expressed sequence tags (ESTs) were assembled into 1,590 unique genes (unigenes). Most of the unigenes were predicted to encode primary metabolism genes, but about 70 were identified as putative secondary metabolism genes. Several of these candidates were analyzed further and full-length cDNA and genomic sequences for a putative 2,3 oxidosqualene cyclase (CAS1) and two BAHD-type acyltransferases (ACT1 and HCT1) were obtained. Homology-based PCR screening for the central gene in plant serotonin biosynthesis, tryptophan decarboxylase (TDC), identified two TDC-related sequences in A. racemosa. CAS1, ACT1, and HCT1 were expressed in most plant tissues, whereas expression of TDC genes was detected only sporadically in immature flower heads and some very young leaf tissues. The cDNA libraries described and assorted genes identified provide initial insight into gene content and diversity in black cohosh, and provide tools and resources for detailed investigations of secondary metabolite genes and enzymes in this important medicinal plant.
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Affiliation(s)
- Martin J Spiering
- Fischell Department of Bioengineering, Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
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Ramani S, Jayabaskaran C. Enhanced catharanthine and vindoline production in suspension cultures of Catharanthus roseus by ultraviolet-B light. J Mol Signal 2008; 3:9. [PMID: 18439256 PMCID: PMC2386454 DOI: 10.1186/1750-2187-3-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 04/25/2008] [Indexed: 11/10/2022] Open
Abstract
Suspension cultures of Catharanthus roseus were used to evaluate ultraviolet-B (UV-B) treatment as an abiotic elicitor of secondary metabolites. A dispersed cell suspension culture from C. roseus leaves in late exponential phase and stationary phase were irradiated with UV-B for 5 min. The stationary phase cultures were more responsive to UV-B irradiation than late exponential phase cultures. Catharanthine and vindoline increased 3-fold and 12-fold, respectively, on treatment with a 5-min UV-B irradiation.
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Affiliation(s)
- Shilpa Ramani
- Department of Biochemistry, Indian Institute of Science, Bangalore - 560012, India.
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Ramani S, Chelliah J. UV-B-induced signaling events leading to enhanced-production of catharanthine in Catharanthus roseus cell suspension cultures. BMC PLANT BIOLOGY 2007; 7:61. [PMID: 17988378 PMCID: PMC2213653 DOI: 10.1186/1471-2229-7-61] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 11/07/2007] [Indexed: 05/18/2023]
Abstract
BACKGROUND Elicitations are considered to be an important strategy towards improved in vitro production of secondary metabolites. In cell cultures, biotic and abiotic elicitors have effectively stimulated the production of plant secondary metabolites. However, molecular basis of elicitor-signaling cascades leading to increased production of secondary metabolites of plant cell is largely unknown. Exposure of Catharanthus roseus cell suspension culture to low dose of UV-B irradiation was found to increase the amount of catharanthine and transcription of genes encoding tryptophan decarboxylase (Tdc) and strictosidine synthase (Str). In the present study, the signaling pathway mediating UV-B-induced catharanthine accumulation in C. roseus suspension cultures were investigated. RESULTS Here, we investigate whether cell surface receptors, medium alkalinization, Ca2+ influx, H2O2, CDPK and MAPK play required roles in UV-B signaling leading to enhanced production of catharanthine in C. roseus cell suspension cultures. C. roseus cells were pretreated with various agonists and inhibitors of known signaling components and their effects on the accumulation of Tdc and Str transcripts as well as amount of catharanthine production were investigated by various molecular biology techniques. It has been found that the catharanthine accumulation and transcription of Tdc and Str were inhibited by 3-4 fold upon pretreatment of various inhibitors like suramin, N-acetyl cysteine, inhibitors of calcium fluxes, staurosporine etc. CONCLUSION Our results demonstrate that cell surface receptor(s), Ca2+ influx, medium alkalinization, CDPK, H2O2 and MAPK play significant roles in UV-B signaling leading to stimulation of Tdc and Str genes and the accumulation of catharanthine in C. roseus cell suspension cultures. Based on these findings, a model for signal transduction cascade has been proposed.
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Affiliation(s)
- Shilpa Ramani
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
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Ramani S, Chelliah J. UV-B-induced signaling events leading to enhanced-production of catharanthine in Catharanthus roseus cell suspension cultures. BMC PLANT BIOLOGY 2007. [PMID: 17988378 DOI: 10.1186/1471-2229-7-61corde] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
BACKGROUND Elicitations are considered to be an important strategy towards improved in vitro production of secondary metabolites. In cell cultures, biotic and abiotic elicitors have effectively stimulated the production of plant secondary metabolites. However, molecular basis of elicitor-signaling cascades leading to increased production of secondary metabolites of plant cell is largely unknown. Exposure of Catharanthus roseus cell suspension culture to low dose of UV-B irradiation was found to increase the amount of catharanthine and transcription of genes encoding tryptophan decarboxylase (Tdc) and strictosidine synthase (Str). In the present study, the signaling pathway mediating UV-B-induced catharanthine accumulation in C. roseus suspension cultures were investigated. RESULTS Here, we investigate whether cell surface receptors, medium alkalinization, Ca2+ influx, H2O2, CDPK and MAPK play required roles in UV-B signaling leading to enhanced production of catharanthine in C. roseus cell suspension cultures. C. roseus cells were pretreated with various agonists and inhibitors of known signaling components and their effects on the accumulation of Tdc and Str transcripts as well as amount of catharanthine production were investigated by various molecular biology techniques. It has been found that the catharanthine accumulation and transcription of Tdc and Str were inhibited by 3-4 fold upon pretreatment of various inhibitors like suramin, N-acetyl cysteine, inhibitors of calcium fluxes, staurosporine etc. CONCLUSION Our results demonstrate that cell surface receptor(s), Ca2+ influx, medium alkalinization, CDPK, H2O2 and MAPK play significant roles in UV-B signaling leading to stimulation of Tdc and Str genes and the accumulation of catharanthine in C. roseus cell suspension cultures. Based on these findings, a model for signal transduction cascade has been proposed.
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Affiliation(s)
- Shilpa Ramani
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India.
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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: 0.4] [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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The Vinca Alkaloids: From Biosynthesis and Accumulation in Plant Cells, to Uptake, Activity and Metabolism in Animal Cells. STUDIES IN NATURAL PRODUCTS CHEMISTRY 2006. [DOI: 10.1016/s1572-5995(06)80041-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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Pauw B, Hilliou FAO, Martin VS, Chatel G, de Wolf CJF, Champion A, Pré M, van Duijn B, Kijne JW, van der Fits L, Memelink J. Zinc finger proteins act as transcriptional repressors of alkaloid biosynthesis genes in Catharanthus roseus. J Biol Chem 2004; 279:52940-8. [PMID: 15465826 DOI: 10.1074/jbc.m404391200] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In Catharanthus roseus cell suspensions, the expression of several terpenoid indole alkaloid biosynthetic genes, including two genes encoding strictosidine synthase (STR) and tryptophan decarboxylase (TDC), is coordinately induced by fungal elicitors such as yeast extract. To identify molecular mechanisms regulating the expression of these genes, a yeast one-hybrid screening was performed with an elicitor-responsive part of the TDC promoter. This screening identified three members of the Cys(2)/His(2)-type (transcription factor IIIA-type) zinc finger protein family from C. roseus, ZCT1, ZCT2, and ZCT3. These proteins bind in a sequence-specific manner to the TDC and STR promoters in vitro and repress the activity of these promoters in trans-activation assays. In addition, the ZCT proteins can repress the activating activity of APETALA2/ethylene response-factor domain transcription factors, the ORCAs, on the STR promoter. The expression of the ZCT genes is rapidly induced by yeast extract and methyljasmonate. These results suggest that the ZCT proteins act as repressors in the regulation of elicitor-induced secondary metabolism in C. roseus.
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Affiliation(s)
- Bea Pauw
- Institute of Biology, Leiden University, Clusius Laboratory, Wassenaarseweg 64, 2333 AL Leiden, The Netherlands
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Michinov N, Michinov E, Toczek-Capelle MC. Social Identity, Group Processes, and Performance in Synchronous Computer-Mediated Communication. ACTA ACUST UNITED AC 2004. [DOI: 10.1037/1089-2699.8.1.27] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Chapter seven Multiple levels of control in the regulation of alkaloid biosynthesis. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0079-9920(03)80022-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Gantet P, Memelink J. Transcription factors: tools to engineer the production of pharmacologically active plant metabolites. Trends Pharmacol Sci 2002; 23:563-9. [PMID: 12457774 DOI: 10.1016/s0165-6147(02)02098-9] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Plants produce a variety of secondary metabolites, some of which are used as pharmaceuticals or are health promoting as food components. Recent genetic studies on the flavonoid biosynthetic pathway show that transcription factors are efficient new molecular tools for plant metabolic engineering to increase the production of valuable compounds. The use of specific transcription factors would avoid the time-consuming step of acquiring knowledge about all enzymatic steps of a poorly characterized biosynthetic pathway. Although genetic approaches are difficult for most plant species, promoter studies of single-pathway genes and T-DNA activation tagging are feasible alternative approaches for isolating transcription factors, as illustrated for terpenoid indole alkaloid biosynthesis in Catharanthus roseus.
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Affiliation(s)
- Pascal Gantet
- Université de Tours, EA 2106, Biomolécules et Biotechnologies Végétales, UFR des Sciences et Techniques, Laboratoire de Physiologie Végétale, Parc de Grandmont, France.
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De Luca V, Laflamme P. The expanding universe of alkaloid biosynthesis. CURRENT OPINION IN PLANT BIOLOGY 2001; 4:225-33. [PMID: 11312133 DOI: 10.1016/s1369-5266(00)00165-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Characterization of many of the major gene families responsible for the generation of central intermediates and for their decoration, together with the development of large genomics and proteomics databases, has revolutionized our capability to identify exotic and interesting natural-product pathways. Over the next few years, these tools will facilitate dramatic advances in our knowledge of the biosynthesis of alkaloids, which will far surpass that which we have learned in the past 50 years. These tools will also be exploited for the rapid characterization of regulatory genes, which control the development of specialized cell factories for alkaloid biosynthesis.
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Affiliation(s)
- V De Luca
- Institut de Recherche en Biologie Végétale, Département de Sciences Biologiques, Université de Montréal, 4101 rue Sherbrooke est, Montréal, H1X 2B2, Québec, Canada.
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21
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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: 285] [Impact Index Per Article: 12.4] [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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Zhao J, Zhu WH, Hu Q. Selection of fungal elicitors to increase indole alkaloid accumulation in catharanthus roseus suspension cell culture. Enzyme Microb Technol 2001; 28:666-672. [PMID: 11339951 DOI: 10.1016/s0141-0229(01)00309-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Various fungal elicitors derived from 12 fungi were tested to improve indole alkaloid production in Catharanthus roseus cell suspension cultures. Results show that different fungal mycelium homogenates stimulate different kinds of indole alkaloid (ajmalicine, serpentine and catharanthine) accumulation, which ranged from 2- to 5-fold higher than the control. Some fungal culture filtrates also efficiently elicited the biosynthesis of different indole alkaloids. The optimal elicitor addition and exposure time for the maximal alkaloid production were on day 7 after subculture and for 3 days of treatment but different fungal elicitors showed the different optimal treatment dosages. Additions of elicitor at the doses ranging from 5 mg/l to 30 mg/l of carbon hydrate equivalent resulted in varieous amounts and kinds of indole alkaloid accumulation. Exposed to a same fungal elicitor, several different cell lines generated the different responses regarding as growth rate, culture color and alkaloid production.
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Affiliation(s)
- J Zhao
- Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Peking, P.R., China
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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: 166] [Impact Index Per Article: 6.9] [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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