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Nishiguchi M, Ali ME, Kaya T, Kobayashi K. Plant virus disease control by vaccination and transgenic approaches: Current status and perspective. PLANT RNA VIRUSES 2023:373-424. [DOI: 10.1016/b978-0-323-95339-9.00028-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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2
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Kernodle SP, Webb S, Steede TM, Lewis RS. Combined reduced expression of two gene families lowers nicotine content to ultra-low levels in cultivated tobacco. PLANT CELL REPORTS 2022; 41:1853-1862. [PMID: 35779084 DOI: 10.1007/s00299-022-02895-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/12/2022] [Indexed: 06/15/2023]
Abstract
KEY MESSAGE Reduced expression of two gene families results in ultra-low nicotine accumulation in Nicotiana tabacum. The potential for mandated lowering of tobacco cigarette filler nicotine levels to below 0.4 mg g-1 is currently being discussed by regulatory and public health organizations. Commercial tobacco cultivars that would routinely meet this proposed standard do not currently exist. Inactivation or silencing of gene families corresponding to single enzymatic steps in the nicotine biosynthetic pathways have not resulted in tobacco genotypes that would meet this standard under conventional agronomic management. Here, we produced and evaluated under field conditions tobacco genotypes expressing an RNAi construct designed to reduce expression of the Methyl Putrescine Oxidase (MPO) gene family associated with nicotine biosynthesis. In a standard flue-cured genetic background, cured leaf nicotine levels were reduced to only 1.08 to 1.65 mg g-1. When MPO RNAi was combined with reduced Berberine Bridge Like (BBL) activity conferred by induced mutations, genotypes producing cured leaf nicotine levels slightly lower than 0.4 mg g-1 were generated. Past research has suggested that MPO activity may contribute to the biosynthesis of nornicotine in a route that does not involve nicotine. However, nornicotine was not reduced to zero in MPO-silenced plants that were also homozygous for induced mutations in known Nicotine Demethylase genes that are responsible for the vast majority of nornicotine accumulation.
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Affiliation(s)
- Sheri P Kernodle
- Department of Crop and Soil Sciences, North Carolina State University, Campus Box 7620, Raleigh, NC, 27695, USA
| | - Sydney Webb
- Department of Crop and Soil Sciences, North Carolina State University, Campus Box 7620, Raleigh, NC, 27695, USA
| | - Tyler M Steede
- Department of Crop and Soil Sciences, North Carolina State University, Campus Box 7620, Raleigh, NC, 27695, USA
| | - Ramsey S Lewis
- Department of Crop and Soil Sciences, North Carolina State University, Campus Box 7620, Raleigh, NC, 27695, USA.
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Gupta D, Dey N, Leelavathi S, Ranjan R. Development of efficient synthetic promoters derived from pararetrovirus suitable for translational research. PLANTA 2021; 253:42. [PMID: 33475866 DOI: 10.1007/s00425-021-03565-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
MAIN CONCLUSION In this study, useful hybrid promoters were developed for efficient ectopic gene expression in monocot and dicot plants, and they hold strong prominence in both transgenic research and biotech industries. This study deals with developing novel synthetic promoters derived from Rice Tungro Bacilliform Virus (RTBV) and Mirabilis Mosaic Virus (MMV). Despite numerous availability, there is a severe scarcity of promoters universally suitable for monocot and dicot plants. Here, eight chimeric promoter constructs were synthesized as gBlocks gene fragments through domain swapping and hybridization by incorporating important domains of previously characterized RTBV and MMV promoters. The developed promoter constructs were assessed for transient GUS expression in tobacco protoplast (Xanthi Brad) and agro-infiltrated tobacco, petunia, rice and pearl millet. Protoplast expression analysis showed that two promoter constructs, namely pUPMA-RP1-MP1GUS and pUPMA-RP4-MP1GUS exhibited 3.56 and 2.5 times higher activities than that of the CaMV35S promoter. We had observed the similar type of expression patterns of these promoters in agroinfiltration-based transient studies. RP1-MP1 and RP4-MP1 promoters exhibited 1.87- and 1.68-fold increase expression in transgenic tobacco plants; while, a 1.95-fold increase was found in RP1-MP1 transgenic rice plants when compared their activities with CaMV35S promoter. Furthermore, on evaluating these promoter constructs for their expression in the bacterial system, pUPMA-RP1-MP1GFP was found to have the highest GFP expression. Moreover, the promoter construct was also evaluated for its capacity to express the HMP3 gene. Biobeads of encapsulated bacterial cells expressing HMP3 gene under control of the pUPMA-RP4-MP1 promoter were found to reduce 72.9% copper and 29.2% zinc concentration from wastewater. Our results had demonstrated that the developed promoter constructs could be used for translational research in dicot, monocot plants and bacterial systems for efficient gene expression.
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Affiliation(s)
- Dipinte Gupta
- Plant Biotechnology Lab, Department of Botany, Faculty of Science, Dayalbagh Educational Institute (Deemed University), Dayalbagh, Agra, 282005, India
| | - Nrisingha Dey
- Institute of Life Science, Nalco Square, Bhubaneshwar, Odisha, 751023, India
| | - Sadhu Leelavathi
- Plant Biology: Plant Transformation Research Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, 110067, India
| | - Rajiv Ranjan
- Plant Biotechnology Lab, Department of Botany, Faculty of Science, Dayalbagh Educational Institute (Deemed University), Dayalbagh, Agra, 282005, India.
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Transgenic tobacco expressing Medicago sativa Defensin (Msdef1) confers resistance to various phyto-pathogens. THE NUCLEUS 2020. [DOI: 10.1007/s13237-020-00307-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Wu W, Liu LL, Yang T, Wang JH, Wang JY, Lv P, Yan YC. Gene expression analysis reveals function of TERF1 in plastid-nucleus retrograde signaling under drought stress conditions. BIOLOGIA PLANTARUM 2018. [PMID: 0 DOI: 10.1007/s10535-018-0771-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
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Lu T, Liu L, Wei M, Liu Y, Qu Z, Yang C, Wei H, Wei Z. The Effect of Poplar PsnGS1.2 Overexpression on Growth, Secondary Cell Wall, and Fiber Characteristics in Tobacco. FRONTIERS IN PLANT SCIENCE 2018; 9:9. [PMID: 29403519 PMCID: PMC5780347 DOI: 10.3389/fpls.2018.00009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 01/03/2018] [Indexed: 05/23/2023]
Abstract
The glutamine synthetase (GS1) is a key enzyme that catalyzes the reaction of glutamate and ammonia to produce glutamine in the nitrogen (N) metabolism. Previous studies on GS1s in several plant species suggest that overexpression of GS1s can enhance N utilization, accelerate plant vegetative growth, and change wood formation. In this study, we isolated a GS1 gene, termed PsnGS1.2, from Populus simonii × Populus nigra. This gene was expressed at a higher level in roots, and relatively lower but detectable levels in xylem, leaves and phloem of P. simonii × P. nigra. The protein encoded by PsnGS1.2 is primarily located in the cytoplasm. Overexpression of PsnGS1.2 in tobacco led to the increased GS1 activity and IAA content, the augmented N assimilation, and the enlarged leaves with altered anatomical structures. These changes presumably promoted photosynthetic, growth, and biomass productivity. It was noteworthy that the secondary cell walls and fiber characteristics changed remarkably in PsnGS1.2 transgenic tobacco. These changes aligned well with the altered expression levels of the genes involved in fiber development, secondary cell wall component biosynthesis, IAA biosynthesis, amino acid transport, and starch breakdown. Taken together, the results from our study suggest that catalytic functions of PsnGS1.2 on N assimilation and metabolism in transgenic tobacco had significant effects on vegetative growth, leaf development, and secondary cell wall formation and properties through acceleration of photosynthesis and IAA biosynthesis, and redirection of carbon flux to synthesis of more cellulose and hemicellulose.
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Affiliation(s)
- Tingting Lu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Lulu Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Minjing Wei
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Yingying Liu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Zianshang Qu
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Chuanping Yang
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
| | - Hairong Wei
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, United States
| | - Zhigang Wei
- State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China
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Khan A, Shrestha A, Bhuyan K, Maiti IB, Dey N. Structural characterization of a novel full-length transcript promoter from Horseradish Latent Virus (HRLV) and its transcriptional regulation by multiple stress responsive transcription factors. PLANT MOLECULAR BIOLOGY 2018; 96:179-196. [PMID: 29327227 DOI: 10.1007/s11103-017-0693-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/04/2017] [Indexed: 06/07/2023]
Abstract
KEY MESSAGE The promoter fragment described in this study can be employed for strong transgene expression under both biotic and abiotic stress conditions. Plant-infecting Caulimoviruses have evolved multiple regulatory mechanisms to address various environmental stimuli during the course of evolution. One such mechanism involves the retention of discrete stress responsive cis-elements which are required for their survival and host-specificity. Here we describe the characterization of a novel Caulimoviral promoter isolated from Horseradish Latent Virus (HRLV) and its regulation by multiple stress responsive Transcription factors (TFs) namely DREB1, AREB1 and TGA1a. The activity of full length transcript (Flt-) promoter from HRLV (- 677 to + 283) was investigated in both transient and transgenic assays where we identified H12 (- 427 to + 73) as the highest expressing fragment having ~ 2.5-fold stronger activity than the CaMV35S promoter. The H12 promoter was highly active and near-constitutive in the vegetative and reproductive parts of both Tobacco and Arabidopsis transgenic plants. Interestingly, H12 contains a distinct cluster of cis-elements like dehydration-responsive element (DRE-core; GCCGAC), an ABA-responsive element (ABRE; ACGTGTC) and as-1 element (TGACG) which are known to be induced by cold, drought and pathogen/SA respectively. The specific binding of DREB1, AREB1 and TGA1a to DRE, ABRE and as-1 elements respectively were confirmed by the gel-binding assays using H12 promoter-specific probes. Detailed mutational analysis of the H12 promoter suggested that the presence of DRE-core and as-1 element was indispensable for its activity which was further confirmed by the transactivation assays. Our studies imply that H12 could be a valuable genetic tool for regulated transgene expression under diverse environmental conditions.
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Affiliation(s)
- Ahamed Khan
- Department of Gene Function and Regulation, Department of Biotechnology, Government of India, Institute of Life Sciences, Chandrasekharpur, Bhubaneswar, Odisha, India
| | - Ankita Shrestha
- Department of Gene Function and Regulation, Department of Biotechnology, Government of India, Institute of Life Sciences, Chandrasekharpur, Bhubaneswar, Odisha, India
| | - Kashyap Bhuyan
- Department of Gene Function and Regulation, Department of Biotechnology, Government of India, Institute of Life Sciences, Chandrasekharpur, Bhubaneswar, Odisha, India
| | - Indu B Maiti
- Department of Molecular Plant Virology and Plant Genetic Engineering, KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, 40546-0236, USA
| | - Nrisingha Dey
- Department of Gene Function and Regulation, Department of Biotechnology, Government of India, Institute of Life Sciences, Chandrasekharpur, Bhubaneswar, Odisha, India.
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8
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Chatterjee A, Das NC, Raha S, Maiti IB, Shrestha A, Khan A, Acharya S, Dey N. Enrichment of apoplastic fluid with therapeutic recombinant protein for efficient biofarming. Biotechnol Prog 2017; 33:726-736. [PMID: 28371174 DOI: 10.1002/btpr.2461] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 01/19/2017] [Indexed: 11/10/2022]
Abstract
OBJECTIVE For efficient biofarming we attempted to enrich plant interstitial fluid (IF)/apoplastic fluid with targeted recombinant therapeutic protein. We employed a synthetic human Glucocerebrosidase (GCB), a model biopharmaceutical protein gene in this study. RESULTS Twenty one Nicotiana varieties, species and hybrids were initially screened for individual IF recovery and based on the findings, we selected Nicotiana tabacum NN (S-9-6), Nicotiana tabacum nn (S-9-7) and Nicotiana benthamiana (S-6-6) as model plants for raising transgenic expressing GCB via Agrobacterium mediated transformation under the control of M24 promoter; GCB specific activity in each transgenic lines were analyzed and we observed higher concentration of recombinant GCB in IF of these transgenic lines (S-9-6, S-9-7, and S-6-6) in comparison to their concentration in crude leaf extracts. CONCLUSION Recovery of valuable therapeutics in plant IF as shown in the present study holds great promise for promoting plant based biofarming. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:726-736, 2017.
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Affiliation(s)
- Aparajita Chatterjee
- Dept. of Molecular Plant Virology and Plant Genetic Engineering, KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, 40546-0236
| | - Narayan C Das
- Dept. of Molecular Plant Virology and Plant Genetic Engineering, KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, 40546-0236
| | - Sumita Raha
- Dept. of Molecular Plant Virology and Plant Genetic Engineering, KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, 40546-0236
| | - Indu B Maiti
- Dept. of Molecular Plant Virology and Plant Genetic Engineering, KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, 40546-0236
| | - Ankita Shrestha
- Dept. of Gene Function and Regulation, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
- Dept. of Biotechnology, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
| | - Ahamed Khan
- Dept. of Gene Function and Regulation, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
- Dept. of Biotechnology, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
| | - Sefali Acharya
- Dept. of Gene Function and Regulation, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
- Dept. of Biotechnology, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
| | - Nrisingha Dey
- Dept. of Gene Function and Regulation, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
- Dept. of Biotechnology, Institute of Life Sciences, Government of India, Chandrasekharpur, Bhubaneswar, Odisha, India
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Abstract
Transgenic resistance to plant viruses is an important technology for control of plant virus infection, which has been demonstrated for many model systems, as well as for the most important plant viruses, in terms of the costs of crop losses to disease, and also for many other plant viruses infecting various fruits and vegetables. Different approaches have been used over the last 28 years to confer resistance, to ascertain whether particular genes or RNAs are more efficient at generating resistance, and to take advantage of advances in the biology of RNA interference to generate more efficient and environmentally safer, novel "resistance genes." The approaches used have been based on expression of various viral proteins (mostly capsid protein but also replicase proteins, movement proteins, and to a much lesser extent, other viral proteins), RNAs [sense RNAs (translatable or not), antisense RNAs, satellite RNAs, defective-interfering RNAs, hairpin RNAs, and artificial microRNAs], nonviral genes (nucleases, antiviral inhibitors, and plantibodies), and host-derived resistance genes (dominant resistance genes and recessive resistance genes), and various factors involved in host defense responses. This review examines the above range of approaches used, the viruses that were tested, and the host species that have been examined for resistance, in many cases describing differences in results that were obtained for various systems developed in the last 20 years. We hope this compilation of experiences will aid those who are seeking to use this technology to provide resistance in yet other crops, where nature has not provided such.
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Affiliation(s)
| | - Peter Palukaitis
- Department of Horticultural Sciences, Seoul Women's University, Seoul, Republic of Korea.
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10
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Sahoo DK, Dey N, Maiti IB. pSiM24 is a novel versatile gene expression vector for transient assays as well as stable expression of foreign genes in plants. PLoS One 2014; 9:e98988. [PMID: 24897541 PMCID: PMC4045853 DOI: 10.1371/journal.pone.0098988] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 05/08/2014] [Indexed: 01/03/2023] Open
Abstract
We have constructed a small and highly efficient binary Ti vector pSiM24 for plant transformation with maximum efficacy. In the pSiM24 vector, the size of the backbone of the early binary vector pKYLXM24 (GenBank Accession No. HM036220; a derivative of pKYLX71) was reduced from 12.8 kb to 7.1 kb. The binary vector pSiM24 is composed of the following genetic elements: left and right T-DNA borders, a modified full-length transcript promoter (M24) of Mirabilis mosaic virus with duplicated enhancer domains, three multiple cloning sites, a 3'rbcsE9 terminator, replication functions for Escherichia coli (ColE1) and Agrobacterium tumefaciens (pRK2-OriV) and the replicase trfA gene, selectable marker genes for kanamycin resistance (nptII) and ampicillin resistance (bla). The pSiM24 plasmid offers a wide selection of cloning sites, high copy numbers in E. coli and a high cloning capacity for easily manipulating different genetic elements. It has been fully tested in transferring transgenes such as green fluorescent protein (GFP) and β-glucuronidase (GUS) both transiently (agro-infiltration, protoplast electroporation and biolistic) and stably in plant systems (Arabidopsis and tobacco) using both agrobacterium-mediated transformation and biolistic procedures. Not only reporter genes, several other introduced genes were also effectively expressed using pSiM24 expression vector. Hence, the pSiM24 vector would be useful for various plant biotechnological applications. In addition, the pSiM24 plasmid can act as a platform for other applications, such as gene expression studies and different promoter expressional analyses.
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Affiliation(s)
- Dipak Kumar Sahoo
- KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, Kentucky, United States of America
| | - Nrisingha Dey
- Department of Gene Function and Regulation, Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Indu Bhushan Maiti
- KTRDC, College of Agriculture, Food and Environment, University of Kentucky, Lexington, Kentucky, United States of America
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11
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Sahoo DK, Raha S, Hall JT, Maiti IB. Overexpression of the synthetic chimeric native-T-phylloplanin-GFP genes optimized for monocot and dicot plants renders enhanced resistance to blue mold disease in tobacco (N. tabacum L.). ScientificWorldJournal 2014; 2014:601314. [PMID: 24778589 PMCID: PMC3980785 DOI: 10.1155/2014/601314] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 02/16/2014] [Indexed: 11/20/2022] Open
Abstract
To enhance the natural plant resistance and to evaluate the antimicrobial properties of phylloplanin against blue mold, we have expressed a synthetic chimeric native-phylloplanin-GFP protein fusion in transgenic Nicotiana tabacum cv. KY14, a cultivar that is highly susceptible to infection by Peronospora tabacina. The coding sequence of the tobacco phylloplanin gene along with its native signal peptide was fused with GFP at the carboxy terminus. The synthetic chimeric gene (native-phylloplanin-GFP) was placed between the modified Mirabilis mosaic virus full-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. The chimeric gene, expressed in transgenic tobacco, was stably inherited in successive plant generations as shown by molecular characterization, GFP quantification, and confocal fluorescent microscopy. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effects due to transgene expression. Blue mold-sensitivity assays of tobacco lines were performed by applying P. tabacina sporangia to the upper leaf surface. Transgenic lines expressing the fused synthetic native-phyllopanin-GFP gene in the leaf apoplast showed resistance to infection. Our results demonstrate that in vivo expression of a synthetic fused native-phylloplanin-GFP gene in plants can potentially achieve natural protection against microbial plant pathogens, including P. tabacina in tobacco.
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Affiliation(s)
- Dipak K. Sahoo
- Kentucky Tobacco Research and Development Center, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546-0236, USA
| | - Sumita Raha
- Kentucky Tobacco Research and Development Center, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546-0236, USA
- Department of Radiation Oncology, Feinberg School of Medicine, Northwestern University, Ward-13-002, 303 East Chicago Avenue, Chicago, IL 60611, USA
| | - James T. Hall
- Kentucky Tobacco Research and Development Center, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546-0236, USA
| | - Indu B. Maiti
- Kentucky Tobacco Research and Development Center, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546-0236, USA
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Sorel M, Garcia JA, German-Retana S. The Potyviridae cylindrical inclusion helicase: a key multipartner and multifunctional protein. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:215-226. [PMID: 24405034 DOI: 10.1094/mpmi-11-13-0333-cr] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A unique feature shared by all plant viruses of the Potyviridae family is the induction of characteristic pinwheel-shaped inclusion bodies in the cytoplasm of infected cells. These cylindrical inclusions are composed of the viral-encoded cylindrical inclusion helicase (CI protein). Its helicase activity was characterized and its involvement in replication demonstrated through different reverse genetics approaches. In addition to replication, the CI protein is also involved in cell-to-cell and long-distance movements, possibly through interactions with the recently discovered viral P3N-PIPO protein. Studies over the past two decades demonstrate that the CI protein is present in several cellular compartments interacting with viral and plant protein partners likely involved in its various roles in different steps of viral infection. Furthermore, the CI protein acts as an avirulence factor in gene-for-gene interactions with dominant-resistance host genes and as a recessive-resistance overcoming factor. Although a significant amount of data concerning the potential functions and subcellular localization of this protein has been published, no synthetic review is available on this important multifunctional protein. In this review, we compile and integrate all information relevant to the current understanding of this viral protein structure and function and present a mode of action for CI, combining replication and movement.
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Kittur FS, Bah M, Archer-Hartmann S, Hung CY, Azadi P, Ishihara M, Sane DC, Xie J. Cytoprotective effect of recombinant human erythropoietin produced in transgenic tobacco plants. PLoS One 2013; 8:e76468. [PMID: 24124563 PMCID: PMC3790672 DOI: 10.1371/journal.pone.0076468] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 08/28/2013] [Indexed: 11/19/2022] Open
Abstract
Asialo-erythropoietin, a desialylated form of human erythropoietin (EPO) lacking hematopoietic activity, is receiving increased attention because of its broader protective effects in preclinical models of tissue injury. However, attempts to translate its protective effects into clinical practice is hampered by unavailability of suitable expression system and its costly and limit production from expensive mammalian cell-made EPO (rhuEPO(M)) by enzymatic desialylation. In the current study, we took advantage of a plant-based expression system lacking sialylating capacity but possessing an ability to synthesize complex N-glycans to produce cytoprotective recombinant human asialo-rhuEPO. Transgenic tobacco plants expressing asialo-rhuEPO were generated by stably co-expressing human EPO and β1,4-galactosyltransferase (GalT) genes under the control of double CaMV 35S and glyceraldehyde-3-phosphate gene (GapC) promoters, respectively. Plant-produced asialo-rhuEPO (asialo-rhuEPO(P)) was purified by immunoaffinity chromatography. Detailed N-glycan analysis using NSI-FTMS and MS/MS revealed that asialo-rhuEPO(P) bears paucimannosidic, high mannose-type and complex N-glycans. In vitro cytoprotection assays showed that the asialo-rhuEPO(P) (20 U/ml) provides 2-fold better cytoprotection (44%) to neuronal-like mouse neuroblastoma cells from staurosporine-induced cell death than rhuEPO(M) (21%). The cytoprotective effect of the asialo-rhuEPO(P) was found to be mediated by receptor-initiated phosphorylation of Janus kinase 2 (JAK2) and suppression of caspase 3 activation. Altogether, these findings demonstrate that plants are a suitable host for producing cytoprotective rhuEPO derivative. In addition, the general advantages of plant-based expression system can be exploited to address the cost and scalability issues related to its production.
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Affiliation(s)
- Farooqahmed S. Kittur
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute & Technology Enterprise, North Carolina Central University, Durham, North Carolina, United States of America
| | - Mamudou Bah
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute & Technology Enterprise, North Carolina Central University, Durham, North Carolina, United States of America
| | - Stephanie Archer-Hartmann
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Chiu-Yueh Hung
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute & Technology Enterprise, North Carolina Central University, Durham, North Carolina, United States of America
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Mayumi Ishihara
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia, United States of America
| | - David C. Sane
- Carilion Clinic and Virginia Tech Carilion School of Medicine, Roanoke, Virginia, United States of America
| | - Jiahua Xie
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute & Technology Enterprise, North Carolina Central University, Durham, North Carolina, United States of America
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Sahoo DK, Stork J, DeBolt S, Maiti IB. Manipulating cellulose biosynthesis by expression of mutant Arabidopsis proM24::CESA3(ixr1-2) gene in transgenic tobacco. PLANT BIOTECHNOLOGY JOURNAL 2013; 11:362-72. [PMID: 23527628 DOI: 10.1111/pbi.12024] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 10/04/2012] [Accepted: 10/05/2012] [Indexed: 05/19/2023]
Abstract
Manipulation of the cellulose biosynthetic machinery in plants has the potential to provide insight into plant growth, morphogenesis and to create modified cellulose for anthropogenic use. Evidence exists that cellulose microfibril structure and its recalcitrance to enzymatic digestion can ameliorated via mis-sense mutation in the primary cell wall-specific gene AtCELLULOSE SYNTHASE (CESA)3. This mis-sense mutation has been identified based on conferring drug resistance to the cellulose inhibitory herbicide isoxaben. To examine whether it would be possible to introduce mutant CESA alleles via a transgenic approach, we overexpressed a modified version of CESA3, AtCESA3(ixr1-2) derived from Arabidopsis thaliana L. Heynh into a different plant family, the Solanceae dicotyledon tobacco (Nicotiana tabacum L. variety Samsun NN). Specifically, a chimeric gene construct of CESA3(ixr1-2) , codon optimized for tobacco, was placed between the heterologous M24 promoter and the rbcSE9 gene terminator. The results demonstrated that the tobacco plants expressing M24-CESA3(ixr1-2) displayed isoxaben resistance, consistent with functionality of the mutated AtCESA3(ixr1-2) in tobacco. Secondly, during enzymatic saccharification, transgenic leaf- and stem-derived cellulose is 54%-66% and 40%-51% more efficient, respectively, compared to the wild type, illustrating translational potential of modified CESA loci. Moreover, the introduction of M24-AtCESA3(ixr1-2) caused aberrant spatial distribution of lignified secondary cell wall tissue and a reduction in the zone occupied by parenchyma cells.
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Affiliation(s)
- Dipak K Sahoo
- KTRDC, College of Agriculture, University of Kentucky, Lexington, KY, USA
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Kumar D, Patro S, Ghosh J, Das A, Maiti IB, Dey N. Development of a salicylic acid inducible minimal sub-genomic transcript promoter from Figwort mosaic virus with enhanced root- and leaf-activity using TGACG motif rearrangement. Gene 2012; 503:36-47. [PMID: 22561698 DOI: 10.1016/j.gene.2012.04.053] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 04/14/2012] [Accepted: 04/18/2012] [Indexed: 11/24/2022]
Abstract
In Figwort mosaic virus sub-genomic transcript promoter (F-Sgt), function of the TGACG-regulatory motif, was investigated in the background of artificially designed promoter sequences. The 131bp (FS, -100 to +31) long F-Sgt promoter sequence containing one TGACG motif [FS-(TGACG)] was engineered to generate a set of three modified promoter constructs: [FS-(TGACG)(2), containing one additional TGACG motif at 7 nucleotides upstream of the original one], [FS-(TGACG)(3), containing two additional TGACG motifs at 7 nucleotides upstream and two nucleotides downstream of the original one] and [FS-(TGCTG)(mu), having a mutated TGACG motif]. EMSA and foot-printing analysis confirmed binding of tobacco nuclear factors with modified TGACG motif/s. The transcription-activation of the GUS gene by the TGACG motif/s in above promoter constructs was examined in transgenic tobacco and Arabidopsis plants and observed that the transcription activation was affected by the spacing/s and number/s of the TGACG motif/s. The FS-(TGACG)(2) promoter showed strongest root-activity compared to other modified and CaMV35S promoters. Also under salicylic acid (SA) stress, the leaf-activity of the said promoter was further enhanced. All above findings were confirmed by real-time and semi-qRT PCR analysis. Taken together, these results clearly demonstrated that the TGACG motif plays an important role in inducing the root-specific expression of the F-Sgt promoter. This study advocates the importance of genetic manipulation of functional cis-motif for amending the tissue specificity of a plant promoter. SA inducible FS-(TGACG)(2) promoter with enhanced activity could be a useful candidate promoter for developing plants with enhanced crop productivity.
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Affiliation(s)
- Deepak Kumar
- Department of Gene Function and Regulation, Institute of Life Sciences, Government of India, Chandrasekherpur, Orissa, India.
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Kumar D, Patro S, Ranjan R, Sahoo DK, Maiti IB, Dey N. Development of useful recombinant promoter and its expression analysis in different plant cells using confocal laser scanning microscopy. PLoS One 2011; 6:e24627. [PMID: 21931783 PMCID: PMC3170401 DOI: 10.1371/journal.pone.0024627] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 08/16/2011] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Designing functionally efficient recombinant promoters having reduced sequence homology and enhanced promoter activity will be an important step toward successful stacking or pyramiding of genes in a plant cell for developing transgenic plants expressing desired traits(s). Also basic knowledge regarding plant cell specific expression of a transgene under control of a promoter is crucial to assess the promoter's efficacy. METHODOLOGY/PRINCIPAL FINDINGS We have constructed a set of 10 recombinant promoters incorporating different up-stream activation sequences (UAS) of Mirabilis mosaic virus sub-genomic transcript (MS8, -306 to +27) and TATA containing core domains of Figwort mosaic virus sub-genomic transcript promoter (FS3, -271 to +31). Efficacies of recombinant promoters coupled to GUS and GFP reporter genes were tested in tobacco protoplasts. Among these, a 369-bp long hybrid sub-genomic transcript promoter (MSgt-FSgt) showed the highest activity in both transient and transgenic systems. In a transient system, MSgt-FSgt was 10.31, 2.86 and 2.18 times more active compared to the CaMV35S, MS8 and FS3 promoters, respectively. In transgenic tobacco (Nicotiana tabaccum, var. Samsun NN) and Arabidopsis plants, the MSgt-FSgt hybrid promoter showed 14.22 and 7.16 times stronger activity compared to CaMV35S promoter respectively. The correlation between GUS activity and uidA-mRNA levels in transgenic tobacco plants were identified by qRT-PCR. Both CaMV35S and MSgt-FSgt promoters caused gene silencing but the degree of silencing are less in the case of the MSgt-FSgt promoter compared to CaMV35S. Quantification of GUS activity in individual plant cells driven by the MSgt-FSgt and the CaMV35S promoter were estimated using confocal laser scanning microscopy and compared. CONCLUSION AND SIGNIFICANCE We propose strong recombinant promoter MSgt-FSgt, developed in this study, could be very useful for high-level constitutive expression of transgenes in a wide variety of plant cells.
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Affiliation(s)
- Deepak Kumar
- Department of Gene Function and Regulation, Institute of Life Sciences, Department of Biotechnology, Government of India, Nalco Square, Chandrasekherpur, Bhubaneswar, Orissa, India
| | - Sunita Patro
- Department of Gene Function and Regulation, Institute of Life Sciences, Department of Biotechnology, Government of India, Nalco Square, Chandrasekherpur, Bhubaneswar, Orissa, India
| | - Rajiv Ranjan
- Department of Gene Function and Regulation, Institute of Life Sciences, Department of Biotechnology, Government of India, Nalco Square, Chandrasekherpur, Bhubaneswar, Orissa, India
| | - Dipak K. Sahoo
- Department of Gene Function and Regulation, Institute of Life Sciences, Department of Biotechnology, Government of India, Nalco Square, Chandrasekherpur, Bhubaneswar, Orissa, India
- Kentucky Tobacco Research and Development Center (KTRDC), College of Agriculture, University of Kentucky, Lexington, Kentucky, United States of America
| | - Indu B. Maiti
- Kentucky Tobacco Research and Development Center (KTRDC), College of Agriculture, University of Kentucky, Lexington, Kentucky, United States of America
| | - Nrisingha Dey
- Department of Gene Function and Regulation, Institute of Life Sciences, Department of Biotechnology, Government of India, Nalco Square, Chandrasekherpur, Bhubaneswar, Orissa, India
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Hu Q, Niu Y, Zhang K, Liu Y, Zhou X. Virus-derived transgenes expressing hairpin RNA give immunity to Tobacco mosaic virus and Cucumber mosaic virus. Virol J 2011; 8:41. [PMID: 21269519 PMCID: PMC3038950 DOI: 10.1186/1743-422x-8-41] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 01/27/2011] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND An effective method for obtaining resistant transgenic plants is to induce RNA silencing by expressing virus-derived dsRNA in plants and this method has been successfully implemented for the generation of different plant lines resistant to many plant viruses. RESULTS Inverted repeats of the partial Tobacco mosaic virus (TMV) movement protein (MP) gene and the partial Cucumber mosaic virus (CMV) replication protein (Rep) gene were introduced into the plant expression vector and the recombinant plasmids were transformed into Agrobacterium tumefaciens. Agrobacterium-mediated transformation was carried out and three transgenic tobacco lines (MP16-17-3, MP16-17-29 and MP16-17-58) immune to TMV infection and three transgenic tobacco lines (Rep15-1-1, Rep15-1-7 and Rep15-1-32) immune to CMV infection were obtained. Virus inoculation assays showed that the resistance of these transgenic plants could inherit and keep stable in T₄ progeny. The low temperature (15 °C did not influence the resistance of transgenic plants. There was no significant correlation between the resistance and the copy number of the transgene. CMV infection could not break the resistance to TMV in the transgenic tobacco plants expressing TMV hairpin MP RNA. CONCLUSIONS We have demonstrated that transgenic tobacco plants expressed partial TMV movement gene and partial CMV replicase gene in the form of an intermolecular intron-hairpin RNA exhibited complete resistance to TMV or CMV infection.
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Affiliation(s)
- Qiong Hu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, P.R. China
- Hangzhou Wanxiang polytechnic, Hangzhou, 310023, P.R. China
| | - Yanbing Niu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, P.R. China
| | - Kai Zhang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, P.R. China
| | - Yong Liu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, P.R. China
| | - Xueping Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310029, P.R. China
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Genetically engineered virus-resistant plants in developing countries: current status and future prospects. Adv Virus Res 2010; 75:185-220. [PMID: 20109667 DOI: 10.1016/s0065-3527(09)07506-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Plant viruses cause severe crop losses worldwide. Conventional control strategies, such as cultural methods and biocide applications against arthropod, nematode, and plasmodiophorid vectors, have limited success at mitigating the impact of plant viruses. Planting resistant cultivars is the most effective and economical way to control plant virus diseases. Natural sources of resistance have been exploited extensively to develop virus-resistant plants by conventional breeding. Non-conventional methods have also been used successfully to confer virus resistance by transferring primarily virus-derived genes, including viral coat protein, replicase, movement protein, defective interfering RNA, non-coding RNA sequences, and protease, into susceptible plants. Non-viral genes (R genes, microRNAs, ribosome-inactivating proteins, protease inhibitors, dsRNAse, RNA modifying enzymes, and scFvs) have also been used successfully to engineer resistance to viruses in plants. Very few genetically engineered (GE) virus resistant (VR) crops have been released for cultivation and none is available yet in developing countries. However, a number of economically important GEVR crops, transformed with viral genes are of great interest in developing countries. The major issues confronting the production and deregulation of GEVR crops in developing countries are primarily socio-economic and related to intellectual property rights, biosafety regulatory frameworks, expenditure to generate GE crops and opposition by non-governmental activists. Suggestions for satisfactory resolution of these factors, presumably leading to field tests and deregulation of GEVR crops in developing countries, are given.
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Shand K, Theodoropoulos C, Stenzel D, Dale JL, Harrison MD. Expression of Potato virus Y cytoplasmic inclusion protein in tobacco results in disorganization of parenchyma cells, distortion of epidermal cells, and induces mitochondrial and chloroplast abnormalities, formation of membrane whorls and atypical lipid accumulation. Micron 2009; 40:730-6. [PMID: 19477654 DOI: 10.1016/j.micron.2009.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 04/27/2009] [Accepted: 04/28/2009] [Indexed: 10/20/2022]
Abstract
Infection of plant cells by potyviruses induces the formation of cytoplasmic inclusions ranging in size from 200 to 1000 nm. To determine if the ability to form these ordered, insoluble structures is intrinsic to the potyviral cytoplasmic inclusion protein, we have expressed the cytoplasmic inclusion protein from Potato virus Y in tobacco under the control of the chrysanthemum ribulose-1,5-bisphosphate carboxylase small subunit promoter, a highly active, green tissue promoter. No cytoplasmic inclusions were observed in the leaves of transgenic tobacco using transmission electron microscopy, despite being able to clearly visualize these inclusions in Potato virus Y infected tobacco leaves under the same conditions. However, we did observe a wide range of tissue and sub-cellular abnormalities associated with the expression of the Potato virus Y cytoplasmic inclusion protein. These changes included the disruption of normal cell morphology and organization in leaves, mitochondrial and chloroplast internal reorganization, and the formation of atypical lipid accumulations. Despite these significant structural changes, however, transgenic tobacco plants were viable and the results are discussed in the context of potyviral cytoplasmic inclusion protein function.
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Affiliation(s)
- Kylie Shand
- Centre for Tropical Crops and Biocommodities, Queensland University of Technology, 2 George Street, Brisbane, Queensland 4001, Australia
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Mialoundama AS, Heintz D, Debayle D, Rahier A, Camara B, Bouvier F. Abscisic acid negatively regulates elicitor-induced synthesis of capsidiol in wild tobacco. PLANT PHYSIOLOGY 2009; 150:1556-66. [PMID: 19420326 PMCID: PMC2705044 DOI: 10.1104/pp.109.138420] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Accepted: 05/01/2009] [Indexed: 05/04/2023]
Abstract
In the Solanaceae, biotic and abiotic elicitors induce de novo synthesis of sesquiterpenoid stress metabolites known as phytoalexins. Because plant hormones play critical roles in the induction of defense-responsive genes, we have explored the effect of abscisic acid (ABA) on the synthesis of capsidiol, the major wild tobacco (Nicotiana plumbaginifolia) sesquiterpenoid phytoalexin, using wild-type plants versus nonallelic mutants Npaba2 and Npaba1 that are deficient in ABA synthesis. Npaba2 and Npaba1 mutants exhibited a 2-fold higher synthesis of capsidiol than wild-type plants when elicited with either cellulase or arachidonic acid or when infected by Botrytis cinerea. The same trend was observed for the expression of the capsidiol biosynthetic genes 5-epi-aristolochene synthase and 5-epi-aristolochene hydroxylase. Treatment of wild-type plants with fluridone, an inhibitor of the upstream ABA pathway, recapitulated the behavior of Npaba2 and Npaba1 mutants, while the application of exogenous ABA reversed the enhanced synthesis of capsidiol in Npaba2 and Npaba1 mutants. Concomitant with the production of capsidiol, we observed the induction of ABA 8'-hydroxylase in elicited plants. In wild-type plants, the induction of ABA 8'-hydroxylase coincided with a decrease in ABA content and with the accumulation of ABA catabolic products such as phaseic acid and dihydrophaseic acid, suggesting a negative regulation exerted by ABA on capsidiol synthesis. Collectively, our data indicate that ABA is not required per se for the induction of capsidiol synthesis but is essentially implicated in a stress-response checkpoint to fine-tune the amplification of capsidiol synthesis in challenged plants.
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Affiliation(s)
- Alexis Samba Mialoundama
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique and Université de Strasbourg, 67084 Strasbourg cedex, France
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Gottula J, Fuchs M. Toward a Quarter Century of Pathogen-Derived Resistance and Practical Approaches to Plant Virus Disease Control. Adv Virus Res 2009; 75:161-83. [DOI: 10.1016/s0065-3527(09)07505-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Tzvetkova-Chevolleau T, Hutin C, Noël LD, Goforth R, Carde JP, Caffarri S, Sinning I, Groves M, Teulon JM, Hoffman NE, Henry R, Havaux M, Nussaume L. Canonical signal recognition particle components can be bypassed for posttranslational protein targeting in chloroplasts. THE PLANT CELL 2007; 19:1635-48. [PMID: 17513500 PMCID: PMC1913721 DOI: 10.1105/tpc.106.048959] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The chloroplast signal recognition particle (cpSRP) and its receptor (cpFtsY) target proteins both cotranslationally and posttranslationally to the thylakoids. This dual function enables cpSRP to utilize its posttranslational activities for targeting a family of nucleus-encoded light-harvesting chlorophyll binding proteins (LHCPs), the most abundant membrane proteins in plants. Previous in vitro experiments indicated an absolute requirement for all cpSRP pathway soluble components. In agreement, a cpFtsY mutant in Arabidopsis thaliana exhibits a severe chlorotic phenotype resulting from a massive loss of LHCPs. Surprisingly, a double mutant, cpftsy cpsrp54, recovers to a great extent from the chlorotic cpftsy phenotype. This establishes that in plants, a new alternative pathway exists that can bypass cpSRP posttranslational targeting activities. Using a mutant form of cpSRP43 that is unable to assemble with cpSRP54, we complemented the cpSRP43-deficient mutant and found that this subunit is required for the alternative pathway. Along with the ability of cpSRP43 alone to bind the ALBINO3 translocase required for LHCP integration, our results indicate that cpSRP43 has developed features to function independently of cpSRP54/cpFtsY in targeting LHCPs to the thylakoid membranes.
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Affiliation(s)
- Tzvetelina Tzvetkova-Chevolleau
- Direction des Sciences du Vivant, Institut de Biologie Environementale et de Biotechnologie, Service de Biologie Végétale et de Microbiologie Environementale, Commissariat à l'Energie Atomique Cadarache, F-13108 Saint-Paul-lez-Durance Cedex, France
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Hou CX, Dirk LMA, Pattanaik S, Das NC, Maiti IB, Houtz RL, Williams MA. Plant peptide deformylase: a novel selectable marker and herbicide target based on essential cotranslational chloroplast protein processing. PLANT BIOTECHNOLOGY JOURNAL 2007; 5:275-81. [PMID: 17309682 DOI: 10.1111/j.1467-7652.2007.00238.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Transgenic tobacco plants expressing three different forms of Arabidopsis plant peptide deformylase (AtDEF1.1, AtDEF1.2 and AtDEF2; EC 3.5.1.88) were evaluated for resistance to actinonin, a naturally occurring peptide deformylase inhibitor. Over-expression of either AtDEF1.2 or AtDEF2 resulted in resistance to actinonin, but over-expression of AtDEF1.1 did not. Immunological analyses demonstrated that AtDEF1.2 and AtDEF2 enzymes were present in both stromal and thylakoid fractions in chloroplasts, but AtDEF1.1 was localized to mitochondria. The highest enzyme activity was associated with stromal AtDEF2, which was approximately 180-fold greater than the level of endogenous activity in the host plant. Resistance to actinonin cosegregated with kanamycin resistance in Atdef1.2-D and Atdef2-D transgenic plants. Here, we demonstrate that the combination of plant peptide deformylase and peptide deformylase inhibitors may represent a native gene selectable marker system for chloroplast and nuclear transformation vectors, and also suggest plant peptide deformylase as a potential broad-spectrum herbicide target.
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Affiliation(s)
- Cai-Xia Hou
- Department of Horticulture, Plant Physiology/Biochemistry/Molecular Biology Program, University of Kentucky, Lexington, KY 40546-0091, USA
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Bouvier F, Linka N, Isner JC, Mutterer J, Weber APM, Camara B. Arabidopsis SAMT1 defines a plastid transporter regulating plastid biogenesis and plant development. THE PLANT CELL 2006; 18:3088-105. [PMID: 17098813 PMCID: PMC1693945 DOI: 10.1105/tpc.105.040741] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2005] [Revised: 09/01/2006] [Accepted: 10/24/2006] [Indexed: 05/12/2023]
Abstract
S-Adenosylmethionine (SAM) is formed exclusively in the cytosol but plays a major role in plastids; SAM can either act as a methyl donor for the biogenesis of small molecules such as prenyllipids and macromolecules or as a regulator of the synthesis of aspartate-derived amino acids. Because the biosynthesis of SAM is restricted to the cytosol, plastids require a SAM importer. However, this transporter has not yet been identified. Here, we report the molecular and functional characterization of an Arabidopsis thaliana gene designated SAM TRANSPORTER1 (SAMT1), which encodes a plastid metabolite transporter required for the import of SAM from the cytosol. Recombinant SAMT1 produced in yeast cells, when reconstituted into liposomes, mediated the counter-exchange of SAM with SAM and with S-adenosylhomocysteine, the by-product and inhibitor of transmethylation reactions using SAM. Insertional mutation in SAMT1 and virus-induced gene silencing of SAMT1 in Nicotiana benthamiana caused severe growth retardation in mutant plants. Impaired function of SAMT1 led to decreased accumulation of prenyllipids and mainly affected the chlorophyll pathway. Biochemical analysis suggests that the latter effect represents one prominent example of the multiple events triggered by undermethylation, when there is decreased SAM flux into plastids.
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Affiliation(s)
- Florence Bouvier
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique and Université Louis Pasteur, 67084 Strasbourg Cedex, France
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Addepalli B, Xu R, Dattaroy T, Li B, Bass WT, Li QQ, Hunt AG. Disease resistance in plants that carry a feedback-regulated yeast poly(A) binding protein gene. PLANT MOLECULAR BIOLOGY 2006; 61:383-97. [PMID: 16830175 DOI: 10.1007/s11103-006-0019-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Accepted: 01/27/2006] [Indexed: 05/10/2023]
Abstract
It has been reported that the expression of the yeast poly(A) binding protein gene (PAB1) in plants leads to an induction of disease resistance responses, accompanied by alterations in the growth habit of the plant (Li et al. Plant Mol. Biol. (2000) 42 335). To capitalize on this observation, a feedback-regulated PAB1 gene was assembled and introduced into tobacco and Arabidopsis. The regulation entailed the linking of the expression of the PAB1 gene to control by the lac repressor, and by linking lac repressor expression to the disease resistance state of the plant, such that the induction of systemic defense responses by accumulation of the yeast poly(A) binding protein would turn off the expression of the PAB1 gene. Plants containing this system showed elevated and/or constitutive expression of disease-associated genes and significant resistance to otherwise pathogenic organisms. As well, they displayed a nearly normal growth habit under laboratory and greenhouse settings. These studies indicate that the expression of cytotoxic genes (such as the PAB1 gene) in plants can be controlled so that enhanced disease resistance can be achieved without significantly affecting plant growth and development.
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Siminszky B, Gavilano L, Bowen SW, Dewey RE. Conversion of nicotine to nornicotine in Nicotiana tabacum is mediated by CYP82E4, a cytochrome P450 monooxygenase. Proc Natl Acad Sci U S A 2005; 102:14919-24. [PMID: 16192354 PMCID: PMC1253577 DOI: 10.1073/pnas.0506581102] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Indexed: 11/18/2022] Open
Abstract
Nornicotine is a secondary tobacco alkaloid that is produced by the N-demethylation of nicotine. Nornicotine production and accumulation in tobacco are undesirable because nornicotine serves as the precursor in the synthesis of the well characterized carcinogen N'-nitrosonornicotine during the curing and processing of tobacco. Although nornicotine is typically a minor alkaloid in tobacco plants, in many tobacco populations a high percentage of individuals can be found that convert a substantial proportion of the nicotine to nornicotine during leaf senescence and curing. We used a microarray-based strategy to identify genes that are differentially regulated between closely related tobacco lines that accumulate either nicotine (nonconverters) or nornicotine (converters) as the predominant alkaloid in the cured leaf. These experiments led to the identification of a small number of closely related cytochrome P450 genes, designated the CYP82E2 family, whose collective transcript levels were consistently higher in converter versus nonconverter tobacco lines. RNA interference-induced silencing of the CYP82E2 gene family suppressed the synthesis of nornicotine in strong converter plants to levels similar to that observed in nonconverter individuals. Although each of the six identified members of the P450 family share >90% nucleotide sequence identity, sense expression of three selected isoforms revealed that only one (CYP82E4v1) was involved in the conversion of nicotine to nornicotine. Yeast expression analysis revealed that CYP82E4v1 functions as a nicotine demethylase. Identification of the gene(s) responsible for nicotine demethylation provides a potentially powerful tool toward efforts to minimize nornicotine levels, and thereby N'-nitrosonornicotine formation, in tobacco products.
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Affiliation(s)
- Balazs Siminszky
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546-0312, USA.
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Dinant S, Ripoll C, Pieper M, David C. Phloem specific expression driven by wheat dwarf geminivirus V-sense promoter in transgenic dicotyledonous species. PHYSIOLOGIA PLANTARUM 2004; 121:108-116. [PMID: 15086824 DOI: 10.1111/j.0031-9317.2004.00296.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Wheat dwarf geminivirus (WDV) is a single-stranded DNA Mastrevirus. The large intergenic region (LIR) of WDV contains cis-acting elements essential for the replication of the genome as well as for the bidirectional transcription of virus genes. The LIR was fused to the GUS (uidA) reporter gene and the WDV viral sense (V-sense) promoter activity derived from the stable integration of that promoter was analysed in transgenic dicot plants. Various dicot species were tested, including Nicotiana tabacum, Nicotiana benthamiana, Arabidopsis thaliana and Cucumis melo. The GUS activity driven by the WDV promoter was also compared to that obtained in plants transformed with the GUS gene controlled by the CaMV 35S promoter as well as two phloem-specific promoters derived from the Arabidopsis thaliana AtSUC2 and AtAHA3 genes. Histochemistry showed that the WDV V-sense promoter consistently induced an expression pattern restricted to the vascular tissues, predominantly in the phloem of all organs. This promoter exhibited levels of GUS activity comparable to that driven by AtSUC2 and AtAHA3 promoters. A vascular expression pattern was observed in the four dicots tested. This was stable during plant development and was not altered following viral infection by an unrelated geminivirus. The uses of such a promoter are discussed regarding the targeting to the phloem of molecules active against vascular pests or pathogens.
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Affiliation(s)
- Sylvie Dinant
- Laboratoire de Biologie Cellulaire, INRA Route de St-Cyr 78026 Versailles, France
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Bhattacharyya S, Pattanaik S, Maiti IB. Intron-mediated enhancement of gene expression in transgenic plants using chimeric constructs composed of the Peanut chlorotic streak virus (PClSV) promoter-leader and the antisense orientation of PClSV ORF VII (p7R). PLANTA 2003; 218:115-24. [PMID: 12883884 DOI: 10.1007/s00425-003-1078-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2002] [Accepted: 06/14/2003] [Indexed: 05/24/2023]
Abstract
The antisense orientation of the Peanut chlorotic streak virus (PClSV) open reading frame (ORF) VII (denoted as p7R), in conjunction with the sense orientation of the PClSV leader sequence, acts as an intron and enhances the expression of a reporter gene, analyzed in protoplasts and transgenic plants of tobacco ( Nicotiana tabacum L.). Correct 5' and 3' splicing sites were determined for intron removal from the chimeric constructs using either beta-glucuronidase (GUS) or chloramphenicol acetyltransferase (CAT) as a reporter gene. In this splicing process, the active consensus 5' splicing donor site (AG/GTATA) is located at position +283 to +289 from the transcription start site (TSS) of the PClSV full-length transcript (FLt). The 3' splice site (TAG/GATT) is located on the p7R sequence at position +785 to +791 from the TSS. The combination of PClSV FLt leader and p7R enhanced the expression of reporter genes (CAT and GUS) by as much as 2-fold compared to the strong constitutive PClSV FLt promoter without an interfering leader sequence and about 30- to 800-fold compared to constructs containing the sense orientation of PClSV ORF VII (p7) in both protoplast transient-expression experiments and stably transformed transgenic plants. An increased level of mature transcripts accompanied this. This suggests that this combination of elements can mediate the intron-mediated enhancement (IME) phenomenon. We also demonstrated comparative IME with other heterologous promoters from caulimoviruses.
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Affiliation(s)
- Somnath Bhattacharyya
- Molecular Plant Virology and Plant Genetic Engineering Laboratory, Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY 40546-0236, USA
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29
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Li B, Huang W, Bass T. Shoot production per responsive leaf explant increases exponentially with explant organogenic potential in Nicotiana species. PLANT CELL REPORTS 2003; 22:231-8. [PMID: 12920564 DOI: 10.1007/s00299-003-0679-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2003] [Revised: 06/22/2003] [Accepted: 06/23/2003] [Indexed: 05/24/2023]
Abstract
As part of the effort to develop optimal plant varieties for the production and molecular farming of plant-made pharmaceuticals, this study evaluated shoot organogenic potential of a total of 115 Nicotiana accessions, representing 53 species. To induce shoots, leaves from seedling grown in vitro were cut into pieces, cultured on shoot-induction medium under low light for 3 weeks, and then subcultured onto the same medium for another 4 weeks under normal light. Statistical analysis detected significant differences among the 115 accessions for the percentage of leaf explants producing shoots and the number of shoots produced per responsive leaf explant. Importantly, regression analysis also found an exponential relationship between the number of shoots produced per responsive leaf explant and the percentage of leaf explants producing shoots. The number of shoots produced per responsive leaf explant increased rather slowly, ranging from zero to around five, as the percentage of leaf explants producing shoots increased from 0 to 80%, but the increase became dramatic as the percentage increased from 80% to 100%, reaching as high as 35 shoots per responsive leaf explant. This exponential relationship is the first of its kind to be established in plant regeneration studies using either organogenesis or somatic embryogenesis systems. A possible mechanism that governs the establishment of the exponential relationship is discussed.
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Affiliation(s)
- B Li
- Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY 40546-0236, USA.
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30
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Maiti IB, Dey N, Pattanaik S, Dahlman DL, Rana RL, Webb BA. Antibiosis-type insect resistance in transgenic plants expressing a teratocyte secretory protein (TSP14) gene from a hymenopteran endoparasite (Microplitis croceipes). PLANT BIOTECHNOLOGY JOURNAL 2003; 1:209-19. [PMID: 17156033 DOI: 10.1046/j.1467-7652.2003.00019.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We have isolated a teratocyte secretory protein (TSP14) gene product from a hymenopteran endoparasite that disrupts the growth of lepidopteran insect larvae. To evaluate the insecticidal activity of TSP14 for the protection of crops from insect damage, chimeric gene constructs of TSP14 were expressed in transgenic plants. The coding sequence of the TSP14 gene, with and without its native signal peptide, was placed between the modified peanut chlorotic streak virus (PClSV) full-length transcript (FLt) promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. These chimeric genes, expressed in transgenic tobacco (Nicotiana tabacum cv. Samsun NN) were stably inherited in successive plant generations (R0, R1 and R2 progeny) as shown by molecular analysis. A Western blot analysis of plant extracts showed the presence of a polypeptide of the expected size that cross-reacted with TSP14-specific antibodies. Larvae of the tobacco budworm (Heliothis virescens) and tobacco hornworm (Manduca sexta) which were fed with several independent homozygous transgenic plant lines (R2 progeny) exhibited mortality and reduced growth rates compared to those fed with plants transformed by a vector control. Our results demonstrate the potential for introduction of the TSP14 gene into plants in order to achieve protection against lepidopteran pests.
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Affiliation(s)
- Indu B Maiti
- Molecular Plant Virology & Plant Genetic Engineering Laboratory at Kentucky Tobacco Research & Development Center, Lexington, KY 40546-0236, USA.
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31
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Bhattacharyya S, Dey N, Maiti IB. Analysis of cis-sequence of subgenomic transcript promoter from the Figwort mosaic virus and comparison of promoter activity with the cauliflower mosaic virus promoters in monocot and dicot cells. Virus Res 2002; 90:47-62. [PMID: 12457962 DOI: 10.1016/s0166-0934(02)00146-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A sub-genomic transcript (Sgt) promoter was isolated from the Figwort mosaic virus (FMV) genomic clone. The FMV Sgt promoter was linked to heterologous coding sequences to form a chimeric gene construct. The 5'-3'-boundaries required for maximal activity and involvement of cis-sequences for optimal expression in plants were defined by 5'-, 3'-end deletion and internal deletion analysis of FMV Sgt promoter fragments coupled with a beta-glucuronidase reporter gene in both transient protoplast expression experiments and in transgenic plants. A 301 bp FMV Sgt promoter fragment (sequence -270 to +31 from the transcription start site; TSS) provided maximum promoter activity. The TSS of the FMV Sgt promoter was determined by primer extension analysis using total RNA from transgenic plants developed for FMV Sgt promoter: uidA fusion gene. An activator domain located upstream of the TATA box at -70 to -100 from TSS is absolutely required for promoter activity and its function is critically position-dependent with respect to TATA box. Two sequence motifs AGATTTTAAT (coordinates -100 to -91) and GTAAGCGC (coordinates -80 to -73) were found to be essential for promoter activity. The FMV Sgt promoter is less active in monocot cells; FMV Sgt promoter expression level was about 27.5-fold higher in tobacco cells compared to that in maize cells. Comparative expression analysis of FMV Sgt promoter with cauliflower mosaic virus (CaMV) 35S promoter showed that the FMV Sgt promoter is about 2-fold stronger than the CaMV 35S promoter. The FMV Sgt promoter is a constitutive promoter; expression level in seedlings was in the order: root>leaf>stem.
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Affiliation(s)
- Somnath Bhattacharyya
- Molecular Plant Virology and Plant Genetic Engineering Laboratory, Tobacco and Health Research Institute, University of Kentucky, Lexington, KY 40546-0236, USA
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32
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Dinkins R, Pflipsen C, Thompson A, Collins GB. Ectopic expression of an Arabidopsis single zinc finger gene in tobacco results in dwarf plants. PLANT & CELL PHYSIOLOGY 2002; 43:743-50. [PMID: 12154136 DOI: 10.1093/pcp/pcf086] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A survey of the Arabidopsis thaliana databases revealed that single C2H2 zinc finger protein genes comprise a large gene family (approximately 30 genes). No known phenotype has been associated with any of these genes except SUPERMAN. One of these genes, designated AtZFP10 (A. thaliana single zinc finger protein), was isolated by RT-PCR in the present study. The AtZFP10 gene was expressed at low levels in the flowers, axillary meristems and siliques, and at very low levels in the stems in Arabidopsis. Overexpression of the AtZFP10 gene driven by a constitutive promoter resulted in abnormal Arabidopsis plants and only one plant was recovered. Tobacco plants overexpressing the AtZFP10 gene displayed dwarfing, abnormal leaf phenotypes and early flowering that correlated with the level of expression of the AtZFP10 gene. No differences were observed in cell size between the AtZFP10 transgenic plants and the wild-type plants. Application of exogenous GA3 did not restore the wild-type phenotype, but it did reduce the dwarfing phenotype. Deletion of the leucine-rich region at the carboxyl terminus of the AtZFP10 gene resulted in transgenic plants that were not phenotypically different from wild-type plants suggesting a role for the leucine-rich region as essential for normal function.
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Affiliation(s)
- Randy Dinkins
- Department of Agronomy, N212 Agriculture Science Center Building North, University of Kentucky, Lexington, KY 40546-0091, USA.
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33
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Sivamani E, Brey CW, Talbert LE, Young MA, Dyer WE, Kaniewski WK, Qu R. Resistance to wheat streak mosaic virus in transgenic wheat engineered with the viral coat protein gene. Transgenic Res 2002; 11:31-41. [PMID: 11874101 DOI: 10.1023/a:1013944011049] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Wheat (Triticum aestivum) plants were stably transformed with the coat protein (CP) gene of wheat streak mosaic virus (WSMV) by the biolistic method. Eleven independently transformed plant lines were obtained and five were analyzed for gene expression and resistance to WSMV. One line showed high resistance to inoculations of two WSMV strains. This line had milder symptoms and lower virus titer than control plants after inoculation. After infection, new growth did not show symptoms. The observed resistance was similar to the 'recovery' type resistance described previously using WSMV NIb transgene and in other systems. This line looked morphologically normal but had an unusually high transgene copy number (approximately 90 copies per 2C homozygous genome). Northern hybridization analysis indicated a high level of degraded CP mRNA expression. However, no coat protein expression was detected.
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Affiliation(s)
- Elumalai Sivamani
- Department of Plant Sciences, Montana State University, Bozeman 59717-3140, USA.
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34
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Du Q, Kende H. Expression of two HOOKLESS genes in peas (Pisum sativum L.). PLANT & CELL PHYSIOLOGY 2001; 42:374-8. [PMID: 11333307 DOI: 10.1093/pcp/pce044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The apical hook of dark-grown dicotyledonous plants results from asymmetric growth of its inner and outer sides. It is a protective structure that prevents damage to the shoot apical meristem and the young leaves as the seedling pushes through the soil. Two phytohormones, ethylene and auxin, are thought to be involved in regulating apical hook formation. HOOKLESS1 (HLS1) of Arabidopsis was recognized as an ethylene-response gene whose product is required for hook formation. We cloned two cDNAs from peas, Ps-HLS1 and Ps-HLS2, whose products are functional homologs of HLS1. Both Ps-HLS1 and Ps-HLS2 complement the hls1 mutation in Arabidopsis. Expression of Ps-HLS1 is enhanced by ethylene and by IAA. Because the effect of ethylene is counteracted by 2,5-norbornadiene, an inhibitor of ethylene action, it appears that the primary factor in apical hook formation in peas is ethylene.
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Affiliation(s)
- Q Du
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824-1312, USA
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35
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Callaway A, Giesman-Cookmeyer D, Gillock ET, Sit TL, Lommel SA. The multifunctional capsid proteins of plant RNA viruses. ANNUAL REVIEW OF PHYTOPATHOLOGY 2001; 39:419-460. [PMID: 11701872 DOI: 10.1146/annurev.phyto.39.1.419] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This article summarizes studies of viral coat (capsid) proteins (CPs) of RNA plant viruses. In addition, we discuss and seek to interpret the knowledge accumulated to data. CPs are named for their primary function; to encapsidate viral genomic nucleic acids. However, encapsidation is only one feature of an extremely diverse array of structural, functional, and ecological roles played during viral infection and spread. Herein, we consider the evolution of viral CPs and their multitude of interactions with factors encoded by the virus, host plant, or viral vector (biological transmission agent) that influence the infection and epidemiological facets of plant disease. In addition, applications of today's understanding of CPs in the protection of crops from viral infection and use in the manufacture of valuable compounds are considered.
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Affiliation(s)
- A Callaway
- Department of Plant Pathology, North Carolina State University, Box 7616, Raleigh, North Carolina 27695-7616, USA.
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36
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Yuan Q, Hu W, Pestka JJ, He SY, Hart LP. Expression of a functional antizearalenone single-chain Fv antibody in transgenic Arabidopsis plants. Appl Environ Microbiol 2000; 66:3499-505. [PMID: 10919813 PMCID: PMC92177 DOI: 10.1128/aem.66.8.3499-3505.2000] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/1999] [Accepted: 05/15/2000] [Indexed: 01/08/2023] Open
Abstract
The efficacy of cloning a recombinant mycotoxin antibody in plants was tested using Arabidopsis as a model. An antizearalenone single-chain Fv (scFv) DNA fragment was first cloned in the newly constructed phage display vector (pEY.5) and then recloned in the plant transformation vector pKYLX71::35S(2). After transformation, constructs of antizearalenone scFv were introduced into immature Arabidopsis seeds via Agrobacterium tumefaciens mediation by vacuum infiltration. Only plants transformed with the construct containing a PR-1b signal peptide sequence produced transgenic offspring. The antizearalenone scFv "plantibody" from these transgenic plants bound zearalenone with a high affinity (50% inhibitory concentration, 11.2 ng/ml) that was comparable to that of bacterially produced scFv antibody and the parent monoclonal antibody (MAb). By electron microscopic immunogold labeling, the presence of antizearalenone scFv was detected mainly in the cytoplasm and only occasionally outside the cell. Like bacterially produced scFv antibody, antizearalenone scFv plantibody exhibited greater sensitivity to methanol destabilization than did the parent MAb. The sensitivity of antizearalenone scFv plantibody to acidic disassociation was similar to the sensitivities of bacterially produced scFv antibody and MAb. Expression of specific plantibodies in crops might be useful for neutralizing mycotoxins in animal feeds and for reducing mycotoxin-associated plant diseases.
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Affiliation(s)
- Q Yuan
- Departments of Botany and Plant Pathology, Michigan State University, East Lansing 48824, USA
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37
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Shen S, Li Q, He SY, Barker KR, Li D, Hunt AG. Conversion of compatible plant-pathogen interactions into incompatible interactions by expression of the Pseudomonas syringae pv. syringae 61 hrmA gene in transgenic tobacco plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2000; 23:205-13. [PMID: 10929114 DOI: 10.1046/j.1365-313x.2000.00772.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The hrmA gene from Pseudomonas syringae pv. syringae has previously been shown to confer avirulence on the virulent bacterium P. syringae pv. tabaci in all examined tobacco cultivars. We expressed this gene in tobacco plants under the control of the tobacco Delta0. 3 TobRB7 promoter, which is induced upon nematode infection in tobacco roots (Opperman et al. 1994, Science, 263, 221-223). A basal level of hrmA expression in leaves of transgenic plants activated the expression of pathogenesis-related genes, and the transgenic plants exhibited high levels of resistance to multiple pathogens: tobacco vein mottling virus, tobacco etch virus, black shank fungus Phytophthora parasitica, and wild fire bacterium Pseudomonas syringae pv. tabaci. However, the hrmA transgenic plants were not significantly more resistant to root-knot nematodes. Our results suggest a potential use of controlled low-level expression of bacterial avr genes, such as hrmA, in plants to generate broad-spectrum resistance to bacterial, fungal and viral pathogens.
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Affiliation(s)
- S Shen
- Department of Agronomy, University of Kentucky, Lexington, KY 40546, USA
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38
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Teycheney PY, Aaziz R, Dinant S, Salánki K, Tourneur C, Balázs E, Jacquemond M, Tepfer M. Synthesis of (-)-strand RNA from the 3' untranslated region of plant viral genomes expressed in transgenic plants upon infection with related viruses. J Gen Virol 2000; 81:1121-6. [PMID: 10725441 DOI: 10.1099/0022-1317-81-4-1121] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
When expressed in transgenic tobacco plants, transgene mRNA that includes the 3' untranslated region (3' UTR) of Lettuce mosaic virus served as template for synthesis of complementary (-)-strand RNA following an infection by Tobacco etch virus, Tobacco vein mottle virus or Pepper mottle virus, but not when infected with Cucumber mosaic virus. Deletion of the 3' UTR from the transgene abolished the synthesis of (-)-strand transcripts. Similar results were obtained in transgenic tobacco plants expressing mRNA that includes the RNA3 3' UTR of Cucumber mosaic virus when infected with Tomato aspermy virus. These results show that the viral RNA-dependent RNA polymerase of several potyviruses and Tomato aspermy virus have the ability to recognize heterologous 3' UTRs when included in transgene mRNAs, and to use them as transcription promoters.
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Affiliation(s)
- P Y Teycheney
- INRA, Laboratoire de biologie cellulaire, F-78026 Versailles cedex, France.
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39
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Li Q, Von Lanken C, Yang J, Lawrence CB, Hunt AG. The yeast polyadenylate-binding protein (PAB1) gene acts as a disease lesion mimic gene when expressed in plants. PLANT MOLECULAR BIOLOGY 2000; 42:335-44. [PMID: 10794533 DOI: 10.1023/a:1006354010997] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We have expressed the gene (PAB1) encoding the yeast polyadenylate-binding protein (Pab1p) in tobacco. Plants that accumulate the Pab1p display a range of abnormalities, ranging from a characteristic chlorosis in leaves to a necrosis and large inhibition of growth. The severity of these abnormalities reflects the levels of yeast Pab1p expression in the transgenic plants. In contrast, no obvious differences could be seen in callus cultures between the transgene and vector control. Plants that display PAB-associated abnormalities were resistant to a range of plant pathogens, and had elevated levels of expression of a pathogenesis-related gene. These two properties--impairment of growth and induction of defense responses--indicate that the yeast PAB1 gene can act as a disease lesion mimic gene in plants.
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Affiliation(s)
- Q Li
- Tobacco and Health Research Institute, University of Kentucky, Lexington 40546-0091, USA
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40
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Gutierrez-Campos R, Torres-Acosta JA, Saucedo-Arias LJ, Gomez-Lim MA. The use of cysteine proteinase inhibitors to engineer resistance against potyviruses in transgenic tobacco plants. Nat Biotechnol 1999; 17:1223-6. [PMID: 10585723 DOI: 10.1038/70781] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
As the processing mechanism of all known potyviruses involves the activity of cysteine proteinases, we asked whether constitutive expression of a rice cysteine proteinase inhibitor gene could induce resistance against two important potyviruses, tobacco etch virus (TEV) and potato virus Y (PVY), in transgenic tobacco plants. Tobacco lines expressing the foreign gene at varying levels were examined for resistance against TEV and PVY infection. There was a clear, direct correlation between the level of oryzacystatin message, inhibition of papain (a cysteine proteinase), and resistance to TEV and PVY in all lines tested. The inhibitor was ineffective against tobacco mosaic virus (TMV) infection because processing of this virus does not involve cysteine proteinases. These results show that plant cystatins can be used against different potyviruses and potentially also against other viruses, whose replication involves cysteine proteinase activity.
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Affiliation(s)
- R Gutierrez-Campos
- Departamento de Química, Centro Básico, Universidad Autónoma de Aguascalientes, Ave. Universidad 940, C.P. 20 100, Aguascalientes, Ags. México
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41
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Hammond J, Lecoq H, Raccah B. Epidemiological risks from mixed virus infections and transgenic plants expressing viral genes. Adv Virus Res 1999; 54:189-314. [PMID: 10547677 DOI: 10.1016/s0065-3527(08)60368-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- J Hammond
- USDA-ARS, U.S. National Arboretum, Floral and Nursery Plants Research Unit, Beltsville, Maryland 20705, USA
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42
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Dey N, Maiti IB. Structure and promoter/leader deletion analysis of mirabilis mosaic virus (MMV) full-length transcript promoter in transgenic plants. PLANT MOLECULAR BIOLOGY 1999; 40:771-82. [PMID: 10487212 DOI: 10.1023/a:1006285426523] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A full-length transcript (FLt) promoter fragment was isolated from a genomic clone of mirabilis mosaic virus (MMV), a double-stranded DNA plant pararetrovirus belonging to the caulimovirus family. The boundaries required for maximal promoter expression were defined by 5' and 3' deletion analysis of the MMV promoter fragments coupled to a GUS reporter gene. The expression patterns of these chimeric gene constructs were evaluated both in transgenic Nicotiana tabacum cv. Samsun NN plants and in protoplast transient expression experiments. A 360 bp FLt promoter fragment (sequence -297 to +63 from the transcription start site) was found sufficient for strong promoter activity. The transcription start site (TSS) of the MMV FLt promoter was determined by primer extension analysis using total RNA isolated from transgenic plants containing a MMV promoter:uidA fusion gene. Analysis of the 5' and 3' deletion constructs showed that an upstream region (sequence -248 to -193 from the transcription start site) is required for the MMV FLt promoter activity along with the as-1, TATA box regions. In addition, a 31 bp sequence (+33 to +63 from the transcription start site) located downstream of a TATA box is also essential for the maximum expression of the MMV FLt promoter. Analysis of transcripts (mRNA) from these chimeric constructs also indicated that the MMV FLt promoter fragment (-297 to +63 from the transcription start site) has the highest promoter activity. In a comparative analysis the MMV FLt promoter showed much greater activity than the CaMV 35S promoter.
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Affiliation(s)
- N Dey
- Molecular Plant Virology and Plant Genetic Engineering Laboratory, Tobacco and Health Research Institute, University of Kentucky, Lexington 40546-0236, USA
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43
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Moreno M, Brandwagt BF, Shaw JG, Rodríguez-Cerezo E. Infectious virus in transgenic plants inoculated with a nonviable, P1-proteinase defective mutant of a potyvirus. Virology 1999; 257:322-9. [PMID: 10329543 DOI: 10.1006/viro.1999.9692] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A mutant (P1-616) of the tobacco vein mottling potyvirus that contains a four-codon insertion in the P1 protein coding region of the viral RNA is unable to infect the normal host plant of the virus. Processing of the P1/HC-Pro cleavage site does not occur during in vitro translation of the mutant viral RNA. When plants transformed with the P1/HC-Pro/P3 coding region of tobacco vein mottling potyvirus RNA were inoculated with P1-616, some of them became infected, although there was a delay in the production of disease symptoms. Virus isolated from these plants was able to infect nontransgenic plants. Two variants of the recovered, infectious virus contained single-nucleotide alterations in the four-codon insertion in the P1-616 genome. In vitro translation of the variant genomic RNAs resulted in partial processing of the P1/HC-Pro cleavage site, although serological analysis of infected tissue showed complete processing in vivo. These results indicate that limited complementation of P1-616 occurs in the transgenic plants and that eventually there arises one or more variants of the mutant sequence that can effect P1/HC-Pro processing and therefore be replicated.
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Affiliation(s)
- M Moreno
- Centro Nacional de Biotecnología (CSIC), Madrid, Cantoblanco, 28049, Spain
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44
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Frey A, Audran C, Marin E, Sotta B, Marion-Poll A. Engineering seed dormancy by the modification of zeaxanthin epoxidase gene expression. PLANT MOLECULAR BIOLOGY 1999; 39:1267-1274. [PMID: 10380812 DOI: 10.1023/a:100614502563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Abscisic acid (ABA) is a plant hormone synthesized during seed development that is involved in the induction of seed dormancy. Delayed germination due to seed dormancy allows long-term seed survival in soil but is generally undesirable in crop species. Freshly harvested seeds of wild-type Nicotiana plumbaginifolia plants exhibit a clear primary dormancy that results in delayed germination, the degree of primary dormancy being influenced by environmental culture conditions of the mother plant. In contrast, seeds, obtained either from ABA-deficient mutant aba2-s1 plants directly or aba2-s1 plants grafted onto wild-type plant stocks, exhibited rapid germination under all conditions irrespective of the mother plant culture conditions. The ABA biosynthesis gene ABA2 of N. plumbaginifolia, encoding zeaxanthin epoxidase, was placed under the control of the constitutive 35S promoter. Transgenic plants overexpressing ABA2 mRNA exhibited delayed germination and increased ABA levels in mature seeds. Expression of an antisense ABA2 mRNA, however, resulted in rapid seed germination and in a reduction of ABA abundance in transgenic seeds. It appears possible, therefore, that seed dormancy can be controlled in this Nicotiana model species by the manipulation of ABA levels.
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MESH Headings
- Abscisic Acid/biosynthesis
- Abscisic Acid/genetics
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genes, Plant/genetics
- Genes, Plant/physiology
- Genetic Engineering
- Germination
- Homozygote
- Mutation
- Oxidoreductases/genetics
- Plant Leaves/genetics
- Plants, Genetically Modified
- Plants, Toxic
- Promoter Regions, Genetic/genetics
- RNA, Antisense/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Seeds/genetics
- Seeds/metabolism
- Seeds/physiology
- Temperature
- Time Factors
- Tobacco/genetics
- Tobacco/physiology
- Transgenes/genetics
- Transgenes/physiology
- Water/metabolism
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Affiliation(s)
- A Frey
- Laboratoire de Biologie Cellulaire, INRA, Versailles, France
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Frey A, Audran C, Marin E, Sotta B, Marion-Poll A. Engineering seed dormancy by the modification of zeaxanthin epoxidase gene expression. PLANT MOLECULAR BIOLOGY 1999; 39:1267-74. [PMID: 10380812 DOI: 10.1023/a:1006145025631] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Abscisic acid (ABA) is a plant hormone synthesized during seed development that is involved in the induction of seed dormancy. Delayed germination due to seed dormancy allows long-term seed survival in soil but is generally undesirable in crop species. Freshly harvested seeds of wild-type Nicotiana plumbaginifolia plants exhibit a clear primary dormancy that results in delayed germination, the degree of primary dormancy being influenced by environmental culture conditions of the mother plant. In contrast, seeds, obtained either from ABA-deficient mutant aba2-s1 plants directly or aba2-s1 plants grafted onto wild-type plant stocks, exhibited rapid germination under all conditions irrespective of the mother plant culture conditions. The ABA biosynthesis gene ABA2 of N. plumbaginifolia, encoding zeaxanthin epoxidase, was placed under the control of the constitutive 35S promoter. Transgenic plants overexpressing ABA2 mRNA exhibited delayed germination and increased ABA levels in mature seeds. Expression of an antisense ABA2 mRNA, however, resulted in rapid seed germination and in a reduction of ABA abundance in transgenic seeds. It appears possible, therefore, that seed dormancy can be controlled in this Nicotiana model species by the manipulation of ABA levels.
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MESH Headings
- Abscisic Acid/biosynthesis
- Abscisic Acid/genetics
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genes, Plant/genetics
- Genes, Plant/physiology
- Genetic Engineering
- Germination
- Homozygote
- Mutation
- Oxidoreductases/genetics
- Plant Leaves/genetics
- Plants, Genetically Modified
- Plants, Toxic
- Promoter Regions, Genetic/genetics
- RNA, Antisense/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Seeds/genetics
- Seeds/metabolism
- Seeds/physiology
- Temperature
- Time Factors
- Nicotiana/genetics
- Nicotiana/physiology
- Transgenes/genetics
- Transgenes/physiology
- Water/metabolism
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Affiliation(s)
- A Frey
- Laboratoire de Biologie Cellulaire, INRA, Versailles, France
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De Leo F, Bonade-Bottino, Ceci, Gallerani, Jouanin. Opposite effects on spodoptera littoralis larvae of high expression level of a trypsin proteinase inhibitor in transgenic plants. PLANT PHYSIOLOGY 1998; 118:997-1004. [PMID: 9808744 PMCID: PMC34810 DOI: 10.1104/pp.118.3.997] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/1998] [Accepted: 08/17/1998] [Indexed: 05/18/2023]
Abstract
This work illustrates potential adverse effects linked with the expression of proteinase inhibitor (PI) in plants used as a strategy to enhance pest resistance. Tobacco (Nicotiana tabacum L. cv Xanthi) and Arabidopsis [Heynh.] ecotype Wassilewskija) transgenic plants expressing the mustard trypsin PI 2 (MTI-2) at different levels were obtained. First-instar larvae of the Egyptian cotton worm (Spodoptera littoralis Boisd.) were fed on detached leaves of these plants. The high level of MTI-2 expression in leaves had deleterious effects on larvae, causing mortality and decreasing mean larval weight, and was correlated with a decrease in the leaf surface eaten. However, larvae fed leaves from plants expressing MTI-2 at the low expression level did not show increased mortality, but a net gain in weight and a faster development compared with control larvae. The low MTI-2 expression level also resulted in increased leaf damage. These observations are correlated with the differential expression of digestive proteinases in the larval gut; overexpression of existing proteinases on low-MTI-2-expression level plants and induction of new proteinases on high-MTI-2-expression level plants. These results emphasize the critical need for the development of a PI-based defense strategy for plants obtaining the appropriate PI-expression level relative to the pest's sensitivity threshold to that PI.
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Affiliation(s)
- De Leo F
- Dipartimento di Biochimica e Biologia Moleculare, Universita di Bari, Via Orabona 4, 70126 Bari, Italy (F.D.L., R.G.)
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Dasgupta S, Collins GB, Hunt AG. Co-ordinated expression of multiple enzymes in different subcellular compartments in plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1998; 16:107-116. [PMID: 9807832 DOI: 10.1046/j.1365-313x.1998.00255.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A gene expression system designed for coordinated expression of multiple genes in plants and their targeting to specified subcellular locations was tested. A series of genes encoding polyproteins containing the tobacco vein mottling virus (TVMV) Nla proteinase along with two other reporter genes (those encoding the Escherichia coli acetate kinase (ACK) and Tn9 chloramphenicol, acetyl transferase (CAT) enzymes) were assembled. The respective coding sequences of these genes were separated by a TVMV Nla proteinase recognition sequence. In addition, in some instances, chloroplast targeting information (a transit peptide (TP) from a pea rbcS gene) was incorporated into the polyprotein. We found that the Nla proteinase can be used to express, as individual polypeptides, the ACK and CAT proteins, and that these proteins retain enzymatic activity. Polyproteins with the structure TP-Nla-ACK-CAT or TP-ACK-CAT-Nla failed to yield chloroplast-localized ACK and CAT proteins, although the latter did give rise to a chloroplast-localized ACK-CAT polyprotein. These results indicate that the Nla proteinase acts in cis more rapidly than transport of proteins into the chloroplast, but that chloroplast localization can take place before complete processing of the polyprotein. Polyproteins with the structures ACK-Nla-TP-CAT and TP-ACK-Nla-TP-CAT yielded appropriately processed and targeted ACK and CAT. Our results show that subcellular localization signals can be effectively recognized in the context of a polyprotein, and they suggest an appropriate strategy for simultaneous engineering of multiple subcellular compartments in plants.
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Affiliation(s)
- S Dasgupta
- Department of Agronomy, University of Kentucky, Lexington 40546-0091, USA
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48
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Maiti IB, Richins RD, Shepherd RJ. Gene expression regulated by gene VI of caulimovirus: transactivation of downstream genes of transcripts by gene VI of peanut chlorotic streak virus in transgenic tobacco. Virus Res 1998; 57:113-24. [PMID: 9870580 DOI: 10.1016/s0168-1702(98)00088-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Here we document that the gene VI product of peanut chlorotic streak virus (PClSV), a newly characterized member of the group, transactivates the translation of dicistronic transcripts. Dicistronic expression units have been analyzed both in protoplast transient expression experiments and in transgenic tobacco plants. Transgenic plants containing a dicistronic transcription unit (PClSV-gene VII-GUS) under the control of PClSV full-length transcript promoter with its long leader sequence show a relatively high abundance of the expected transcript but very little, or no, GUS activity. However, high GUS activity is found when gene VI protein is then provided by subsequent infection with PClSV. The efficient translation of polycistronic mRNAs mediated by gene VI of caulimovirus has potential value in product engineering of plants.
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Affiliation(s)
- I B Maiti
- Department of Plant Pathology, Tobacco and Health Research Institute, University of Kentucky, Lexington 40546-0236, USA.
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El Euch C, Jay-Allemand C, Pastuglia M, Doumas P, Charpentier JP, Capelli P, Jouanin L. Expression of antisense chalcone synthase RNA in transgenic hybrid walnut microcuttings. Effect on flavonoid content and rooting ability. PLANT MOLECULAR BIOLOGY 1998; 38:467-479. [PMID: 9747854 DOI: 10.1023/a:1006034709501] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Walnut somatic embryos (Juglans nigra x Juglans regia) were transformed with a vector containing a neomycin phosphotransferase II, a beta-glucuronidase and an antisense chalcone synthase (chs) gene. This antisense construct included a 400 bp cDNA fragment of a walnut chs gene under the control of the duplicated CaMV-35S promoter. Molecular, biochemical and biological characterizations were performed both on transformed embryos propagated by secondary somatic embryogenesis and on microshoots developed by in vitro culture of embryonic epicotyls from somatic embryos. Thirteen transformed lines with the vector containing the antisense chs gene, one line with only the gus and nptII genes and one untransformed line were maintained in tissue culture. Six of the antisense lines were shown to be flavonoid-deficient. They exhibited a strongly reduced expression of chs genes, very low chalcone synthase activity and no detectable amounts of quercitrin, myricitrin, flavane-3-ols and proanthocyanidins in stems. Rooting tests showed that decreased flavonoid content in stems of antisense chs transformed lines was associated with enhanced adventitious root formation. Free auxin and conjugated auxin contents were determined during the latter phase of the micropropagation, and no variations were detected between control and antisense chs transformed lines. The in vitro plants developed a large basal callus and apical necrosis upon auxinic induction and the transformed lines highly deficient in flavonoids were more sensitive to exogenous application of indolebutyric acid (IBA).
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Affiliation(s)
- C El Euch
- Laboratoire de biologie cellulaire, INRA, Versailles, France
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50
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Malpica CA, Cervera MT, Simoens C, Van Montagu M. Engineering resistance against viral diseases in plants. Subcell Biochem 1998; 29:287-320. [PMID: 9594651 DOI: 10.1007/978-1-4899-1707-2_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- C A Malpica
- Department of Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), Universiteit Gent, Belgium
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