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Chen K, Liu H, Blevins T, Hao J, Otten L. Extensive natural Agrobacterium-induced transformation in the genus Camellia. PLANTA 2023; 258:81. [PMID: 37715842 DOI: 10.1007/s00425-023-04234-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/30/2023] [Indexed: 09/18/2023]
Abstract
MAIN CONCLUSION The genus Camellia underwent extensive natural transformation by Agrobacterium. Over a period of 15 million years, at least 12 different inserts accumulated in 72 investigated Camellia species. Like a wide variety of other wild and cultivated plants, Camellia species carry cellular T-DNA sequences (cT-DNAs) in their nuclear genomes, resulting from natural Agrobacterium-mediated transformation. Short and long DNA sequencing reads of 435 accessions belonging to 72 Camellia species (representing 12 out of 14 sections) were investigated for the occurrence of cT-DNA insertions. In all, 12 different cT-DNAs were recovered, either completely or partially, called CaTA to CaTL. Divergence analysis of internal cT-DNA repeats revealed that the insertion events span a period from 0.075 to 15 Mio years ago, and yielded an average transformation frequency of one event per 1.25 Mio years. The two oldest inserts, CaTA and CaTD, have been modified by spontaneous deletions and inversions, and by insertion of various plant sequences. In those cases where enough accessions were available (C. japonica, C. oleifera, C. chekiangoleosa, C. sasanqua and C. pitardii), the younger cT-DNA inserts showed a patchy distribution among different accessions of each species, indicating that they are not genetically fixed. It could be shown that Camellia breeding has led to intersectional transfer of cT-DNAs. Altogether, the cT-DNAs cover 374 kb, and carry 47 open reading frames (ORFs). Two Camellia cT-DNA genes, CaTH-orf358 and CaTK-orf8, represent new types of T-DNA genes. With its large number of cT-DNA sequences, the genus Camellia constitutes an interesting model for the study of natural Agrobacterium transformants.
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Affiliation(s)
- Ke Chen
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China.
| | - Hai Liu
- Shanghai Key Laboratory of Plant Functional Genomics and Resources, Shanghai Chenshan Botanical Garden, Shanghai, 201602, China
| | - Todd Blevins
- Institut de Biologie Moléculaire des Plantes du C.N.R.S., Rue du Général Zimmer 12, 67084, Strasbourg, France
| | - Jie Hao
- Institute of Clinical Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Léon Otten
- Institut de Biologie Moléculaire des Plantes du C.N.R.S., Rue du Général Zimmer 12, 67084, Strasbourg, France
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Zhidkin R, Zhurbenko P, Bogomaz O, Gorodilova E, Katsapov I, Antropov D, Matveeva T. Biodiversity of rolB/C-like Natural Transgene in the Genus Vaccinium L. and Its Application for Phylogenetic Studies. Int J Mol Sci 2023; 24:ijms24086932. [PMID: 37108096 PMCID: PMC10138537 DOI: 10.3390/ijms24086932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/06/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
A variety of plant species found in nature contain agrobacterial T-DNAs in their genomes which they transmit in a series of sexual generations. Such T-DNAs are called cellular T-DNAs (cT-DNAs). cT-DNAs have been discovered in dozens of plant genera, and are suggested to be used in phylogenetic studies, since they are well-defined and unrelated to other plant sequences. Their integration into a particular chromosomal site indicates a founder event and a clear start of a new clade. cT-DNA inserts do not disseminate in the genome after insertion. They can be large and old enough to generate a range of variants, thereby allowing the construction of detailed trees. Unusual cT-DNAs (containing the rolB/C-like gene) were found in our previous study in the genome data of two Vaccinium L. species. Here, we present a deeper study of these sequences in Vaccinium L. Molecular-genetic and bioinformatics methods were applied for sequencing, assembly, and analysis of the rolB/C-like gene. The rolB/C-like gene was discovered in 26 new Vaccinium species and Agapetes serpens (Wight) Sleumer. Most samples were found to contain full-size genes. It allowed us to develop approaches for the phasing of cT-DNA alleles and reconstruct a Vaccinium phylogenetic relationship. Intra- and interspecific polymorphism found in cT-DNA makes it possible to use it for phylogenetic and phylogeographic studies of the Vaccinium genus.
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Affiliation(s)
- Roman Zhidkin
- Department of Genetic and Breeding, St. Petersburg State University, Saint Petersburg 199034, Russia
| | - Peter Zhurbenko
- Department of Genetic and Breeding, St. Petersburg State University, Saint Petersburg 199034, Russia
- Komarov Botanical Institute of the Russian Academy of Sciences, Saint Petersburg 197022, Russia
| | - Olesya Bogomaz
- Faculty of Bioengineering and Bioinformatics, Moscow State University, Moscow 119991, Russia
| | | | - Ivan Katsapov
- Department of Genetic and Breeding, St. Petersburg State University, Saint Petersburg 199034, Russia
| | - Dmitry Antropov
- Department of Genetic and Breeding, St. Petersburg State University, Saint Petersburg 199034, Russia
| | - Tatiana Matveeva
- Department of Genetic and Breeding, St. Petersburg State University, Saint Petersburg 199034, Russia
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3
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Matveeva T, Otten L. Opine biosynthesis in naturally transgenic plants: Genes and products. PHYTOCHEMISTRY 2021; 189:112813. [PMID: 34192603 DOI: 10.1016/j.phytochem.2021.112813] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/03/2021] [Accepted: 05/07/2021] [Indexed: 06/13/2023]
Abstract
The plant pathogen Agrobacterium transfers DNA into plant cells by a specific transfer mechanism. Expression of this transferred DNA or T-DNA leads to crown gall tumors or abnormal, hairy roots and the synthesis of specific compounds, called opines. Opines are produced from common plant metabolites like sugars, amino acids and α-keto acids, which are combined into different low molecular weight structures by T-DNA-encoded opine synthase enzymes. Opines can be converted back by Agrobacterium into the original metabolites and used for agrobacterial growth. Recently it has been discovered that about 7% of Angiosperms carry T-DNA-like sequences. These result from ancient Agrobacterium transformation events, followed by spontaneous regeneration of transformed cells into natural genetically transformed organisms (nGMOs). Nearly all nGMOs identified up to date carry opine synthesis genes, several of these are intact and potentially encode opine synthesis. So far, only tobacco and cuscuta have been demonstrated to contain opines. Whereas opines from crown gall and hairy root tissues have been studied for over 60 years, those from the nGMOs remain to be explored.
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Affiliation(s)
- Tatiana Matveeva
- St. Petersburg State University, University Emb., 7/9, Saint Petersburg, Russia.
| | - Léon Otten
- Institute of Plant Molecular Biology, C.N.R.S, 67084, Strasbourg, France.
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Mauro ML, Bettini PP. Agrobacterium rhizogenes rolB oncogene: An intriguing player for many roles. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 165:10-18. [PMID: 34029941 DOI: 10.1016/j.plaphy.2021.04.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
The rolB oncogene is one of the so-called rol genes found in the T-DNA region of the Agrobacterium rhizogenes Ri plasmid and involved in the hairy root syndrome, a tumour characterized by adventitious root overgrowth on plant stem. rolB produces in plants a peculiar phenotype that, together with its root-inducing capacity, has been connected to auxin sensitivity. The gene is able to modify the plant genetic programme to induce meristem cells and direct them to differentiate not only roots, but also other cells, tissues or organs. Besides its essential function in hairy root pathogenesis, the rolB role has been progressively extended to cover several physiological aspects in the transgenic plants: from secondary metabolites production and ROS inhibition, to abiotic and biotic stress tolerance and photosynthesis improvement. Some of the observed effects could be determined, at least in part, through microRNAs molecules, suggesting an epigenetic control rolB-mediated. These multifaceted capacities could allow plants to withstand adverse environmental conditions, enhancing fitness. In spite of this expanding knowledge, functional analyses did not detect yet any definitive rolB-derived biochemical product, even if more than one enzymatic activity has been ascribed to it. Moreover, phylogenetic and evolutionary studies evidenced no homology with any plant sequences but, otherwise, it belongs to the Plast family, a group of rolB-homologous bacterial genes. Finally, the finding of sequences similar to rolB in plants not infected by A. rhizogenes suggests a hypothetical plant origin for this gene, implying different possibilities about its evolution.
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Affiliation(s)
- Maria Luisa Mauro
- Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, P.le Aldo Moro 5, 00185, Roma, Italy.
| | - Priscilla P Bettini
- Dipartimento di Biologia, Università degli Studi di Firenze, via Madonna del Piano 6, 50019, Sesto f.no, FI, Italy.
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Potuschak T, Palatnik J, Schommer C, Sierro N, Ivanov NV, Kwon Y, Genschik P, Davière J, Otten L. Inhibition of Arabidopsis thaliana CIN-like TCP transcription factors by Agrobacterium T-DNA-encoded 6B proteins. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:1303-1317. [PMID: 31659801 PMCID: PMC7187390 DOI: 10.1111/tpj.14591] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 10/03/2019] [Indexed: 05/26/2023]
Abstract
Agrobacterium T-DNA-encoded 6B proteins cause remarkable growth effects in plants. Nicotiana otophora carries two cellular T-DNAs with three slightly divergent 6b genes (TE-1-6b-L, TE-1-6b-R and TE-2-6b) originating from a natural transformation event. In Arabidopsis thaliana, expression of 2×35S:TE-2-6b, but not 2×35S:TE-1-6b-L or 2×35S:TE-1-6b-R, led to plants with crinkly leaves, which strongly resembled mutants of the miR319a/TCP module. This module is composed of MIR319A and five CIN-like TCP (TEOSINTHE BRANCHED1, CYCLOIDEA and PROLIFERATING CELL NUCLEAR ANTIGEN BINDING FACTOR) genes (TCP2, TCP3, TCP4, TCP10 and TCP24) targeted by miR319a. The CIN-like TCP genes encode transcription factors and are required for cell division arrest at leaf margins during development. MIR319A overexpression causes excessive growth and crinkly leaves. TE-2-6b plants did not show increased miR319a levels, but the mRNA levels of the TCP4 target gene LOX2 were decreased, as in jaw-D plants. Co-expression of green fluorescent protein (GFP)-tagged TCPs with native or red fluorescent protein (RFP)-tagged TE-6B proteins led to an increase in TCP protein levels and formation of numerous cytoplasmic dots containing 6B and TCP proteins. Yeast double-hybrid experiments confirmed 6B/TCP binding and showed that TE-1-6B-L and TE-1-6B-R bind a smaller set of TCP proteins than TE-2-6B. A single nucleotide mutation in TE-1-6B-R enlarged its TCP-binding repertoire to that of TE-2-6B and caused a crinkly phenotype in Arabidopsis. Deletion analysis showed that TE-2-6B targets the TCP4 DNA-binding domain and directly interferes with transcriptional activation. Taken together, these results provide detailed insights into the mechanism of action of the N. otophora TE-encoded 6b genes.
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Affiliation(s)
- Thomas Potuschak
- Institut de Biologie Moléculaire des Plantes (IBMP)Rue du Général Zimmer 1267084StrasbourgFrance
| | - Javier Palatnik
- IBR‐CONICETPredio CCTOcampo y Esmeralda s/n2000RosarioArgentina
| | - Carla Schommer
- IBR‐CONICETPredio CCTOcampo y Esmeralda s/n2000RosarioArgentina
| | - Nicolas Sierro
- PMI R&DPhilip Morris Products S. A.Quai Jeanrenaud 52000NeuchâtelSwitzerland
| | - Nikolai V. Ivanov
- PMI R&DPhilip Morris Products S. A.Quai Jeanrenaud 52000NeuchâtelSwitzerland
| | - Yerim Kwon
- Institut de Biologie Moléculaire des Plantes (IBMP)Rue du Général Zimmer 1267084StrasbourgFrance
| | - Pascal Genschik
- Institut de Biologie Moléculaire des Plantes (IBMP)Rue du Général Zimmer 1267084StrasbourgFrance
| | - Jean‐Michel Davière
- Institut de Biologie Moléculaire des Plantes (IBMP)Rue du Général Zimmer 1267084StrasbourgFrance
| | - Léon Otten
- Institut de Biologie Moléculaire des Plantes (IBMP)Rue du Général Zimmer 1267084StrasbourgFrance
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Rhizogenic agrobacteria as an innovative tool for plant breeding: current achievements and limitations. Appl Microbiol Biotechnol 2020; 104:2435-2451. [PMID: 32002599 DOI: 10.1007/s00253-020-10403-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/16/2020] [Accepted: 01/20/2020] [Indexed: 01/02/2023]
Abstract
Compact plant growth is an economically important trait for many crops. In practice, compactness is frequently obtained by applying chemical plant growth regulators. In view of sustainable and environmental-friendly plant production, the search for viable alternatives is a priority for breeders. Co-cultivation and natural transformation using rhizogenic agrobacteria result in morphological alterations which together compose the Ri phenotype. This phenotype is known to exhibit a more compact plant habit, besides other features. In this review, we highlight the use of rhizogenic agrobacteria and the Ri phenotype with regard to sustainable plant production and plant breeding. An overview of described Ri lines and current breeding applications is presented. The potential of Ri lines as pre-breeding material is discussed from both a practical and legal point of view.
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Paolis AD, Frugis G, Giannino D, Iannelli MA, Mele G, Rugini E, Silvestri C, Sparvoli F, Testone G, Mauro ML, Nicolodi C, Caretto S. Plant Cellular and Molecular Biotechnology: Following Mariotti's Steps. PLANTS (BASEL, SWITZERLAND) 2019; 8:E18. [PMID: 30634627 PMCID: PMC6359066 DOI: 10.3390/plants8010018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/30/2018] [Accepted: 01/07/2019] [Indexed: 01/19/2023]
Abstract
This review is dedicated to the memory of Prof. Domenico Mariotti, who significantly contributed to establishing the Italian research community in Agricultural Genetics and carried out the first experiments of Agrobacterium-mediated plant genetic transformation and regeneration in Italy during the 1980s. Following his scientific interests as guiding principles, this review summarizes the recent advances obtained in plant biotechnology and fundamental research aiming to: (i) Exploit in vitro plant cell and tissue cultures to induce genetic variability and to produce useful metabolites; (ii) gain new insights into the biochemical function of Agrobacterium rhizogenes rol genes and their application to metabolite production, fruit tree transformation, and reverse genetics; (iii) improve genetic transformation in legume species, most of them recalcitrant to regeneration; (iv) untangle the potential of KNOTTED1-like homeobox (KNOX) transcription factors in plant morphogenesis as key regulators of hormonal homeostasis; and (v) elucidate the molecular mechanisms of the transition from juvenility to the adult phase in Prunus tree species.
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Affiliation(s)
- Angelo De Paolis
- Istituto di Scienze delle Produzioni Alimentari (ISPA), Consiglio Nazionale delle Ricerche (CNR), Via Monteroni, 73100 Lecce, Italy.
| | - Giovanna Frugis
- Istituto di Biologia e Biotecnologia Agraria (IBBA), UOS Roma, Consiglio Nazionale delle Ricerche (CNR), Via Salaria Km. 29,300, Monterotondo Scalo, 00015 Roma, Italy.
| | - Donato Giannino
- Istituto di Biologia e Biotecnologia Agraria (IBBA), UOS Roma, Consiglio Nazionale delle Ricerche (CNR), Via Salaria Km. 29,300, Monterotondo Scalo, 00015 Roma, Italy.
| | - Maria Adelaide Iannelli
- Istituto di Biologia e Biotecnologia Agraria (IBBA), UOS Roma, Consiglio Nazionale delle Ricerche (CNR), Via Salaria Km. 29,300, Monterotondo Scalo, 00015 Roma, Italy.
| | - Giovanni Mele
- Istituto di Biologia e Biotecnologia Agraria (IBBA), UOS Roma, Consiglio Nazionale delle Ricerche (CNR), Via Salaria Km. 29,300, Monterotondo Scalo, 00015 Roma, Italy.
| | - Eddo Rugini
- Dipartimento di Scienze Agrarie e Forestali (DAFNE), Università degli Studi della Tuscia, Via San Camillo De Lellis S.N.C., 01100 Viterbo, Italy.
| | - Cristian Silvestri
- Dipartimento di Scienze Agrarie e Forestali (DAFNE), Università degli Studi della Tuscia, Via San Camillo De Lellis S.N.C., 01100 Viterbo, Italy.
| | - Francesca Sparvoli
- Istituto di Biologia e Biotecnologia Agraria (IBBA), Consiglio Nazionale delle Ricerche (CNR), Via Bassini 15, 20133 Milano, Italy.
| | - Giulio Testone
- Istituto di Biologia e Biotecnologia Agraria (IBBA), UOS Roma, Consiglio Nazionale delle Ricerche (CNR), Via Salaria Km. 29,300, Monterotondo Scalo, 00015 Roma, Italy.
| | - Maria Luisa Mauro
- Dipartimento di Biologia e Biotecnologie, Sapienza Università di Roma, P.le A. Moro 5, 00185 Roma, Italy.
| | - Chiara Nicolodi
- Istituto di Biologia e Biotecnologia Agraria (IBBA), UOS Roma, Consiglio Nazionale delle Ricerche (CNR), Via Salaria Km. 29,300, Monterotondo Scalo, 00015 Roma, Italy.
| | - Sofia Caretto
- Istituto di Scienze delle Produzioni Alimentari (ISPA), Consiglio Nazionale delle Ricerche (CNR), Via Monteroni, 73100 Lecce, Italy.
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Trovato M, Mattioli R, Costantino P. From A. rhizogenes RolD to Plant P5CS: Exploiting Proline to Control Plant Development. PLANTS (BASEL, SWITZERLAND) 2018; 7:E108. [PMID: 30563242 PMCID: PMC6313920 DOI: 10.3390/plants7040108] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 11/27/2018] [Accepted: 12/01/2018] [Indexed: 01/14/2023]
Abstract
The capability of the soil bacterium Agrobacterium rhizogenes to reprogram plant development and induce adventitious hairy roots relies on the expression of a few root-inducing genes (rol A, B, C and D), which can be transferred from large virulence plasmids into the genome of susceptible plant cells. Contrary to rolA, B and C, which are present in all the virulent strains of A. rhizogenes and control hairy root formation by affecting auxin and cytokinin signalling, rolD appeared non-essential and not associated with plant hormones. Its role remained elusive until it was discovered that it codes for a proline synthesis enzyme. The finding that, in addition to its role in protein synthesis and stress adaptation, proline is also involved in hairy roots induction, disclosed a novel role for this amino acid in plant development. Indeed, from this initial finding, proline was shown to be critically involved in a number of developmental processes, such as floral transition, embryo development, pollen fertility and root elongation. In this review, we present a historical survey on the rol genes focusing on the role of rolD and proline in plant development.
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Affiliation(s)
- Maurizio Trovato
- Department of Biology and Biotechnology, Sapienza University of Rome, 00185 Rome, Italy.
| | - Roberto Mattioli
- Department of Biology and Biotechnology, Sapienza University of Rome, 00185 Rome, Italy.
| | - Paolo Costantino
- Department of Biology and Biotechnology, Sapienza University of Rome, 00185 Rome, Italy.
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Chen K, Dorlhac de Borne F, Sierro N, Ivanov NV, Alouia M, Koechler S, Otten L. Organization of the TC and TE cellular T-DNA regions in Nicotiana otophora and functional analysis of three diverged TE-6b genes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 94:274-287. [PMID: 29396989 DOI: 10.1111/tpj.13853] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/17/2018] [Accepted: 01/22/2018] [Indexed: 05/27/2023]
Abstract
Nicotiana otophora contains Agrobacterium-derived T-DNA sequences introduced by horizontal gene transfer (Chen et al., 2014). Sixty-nine contigs were assembled into four different cellular T-DNAs (cT-DNAs) totalling 83 kb. TC and TE result from two successive transformation events, each followed by duplication, yielding two TC and two TE inserts. TC is also found in other Nicotiana species, whereas TE is unique to N. otophora. Both cT-DNA regions are partially duplicated inverted repeats. Analysis of the cT-DNA divergence patterns allowed reconstruction of the evolution of the TC and TE regions. TC and TE carry 10 intact open reading frames. Three of these are TE-6b genes, derived from a single 6b gene carried by the Agrobacterium strain which inserted TE in the N. otophora ancestor. 6b genes have so far only been found in Agrobacterium tumefaciens or Agrobacterium vitis T-DNAs and strongly modify plant growth (Chen and Otten, 2016). The TE-6b genes were expressed in Nicotiana tabacum under the constitutive 2 × 35S promoter. TE-1-6b-R and TE-2-6b led to shorter plants, dark-green leaves, a strong increase in leaf vein development and modified petiole wings. TE-1-6b-L expression led to a similar phenotype, but in addition leaves show outgrowths at the margins, flowers were modified and plants became viviparous, i.e. embryos germinated in the capsules at an early stage of their development. Embryos could be rescued by culture in vitro. The TE-6b phenotypes are very different from the earlier described 6b phenotypes and could provide new insight into the mode of action of the 6b genes.
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Affiliation(s)
- Ke Chen
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084, Strasbourg, France
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | | | - Nicolas Sierro
- PMI R&D, Philip Morris Products S.A. [part of Philip Morris International group of companies], Quai Jeanrenaud 5, 2000, Neuchâtel, Switzerland
| | - Nikolai V Ivanov
- PMI R&D, Philip Morris Products S.A. [part of Philip Morris International group of companies], Quai Jeanrenaud 5, 2000, Neuchâtel, Switzerland
| | - Malek Alouia
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084, Strasbourg, France
| | - Sandrine Koechler
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084, Strasbourg, France
| | - Léon Otten
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084, Strasbourg, France
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Abstract
The transfer of T-DNA sequences from Agrobacterium to plant cells is a well-understood process of natural genetic engineering. The expression of T-DNA genes in plants leads to tumors, hairy roots, or transgenic plants. The transformed cells multiply and synthesize small molecules, called opines, used by Agrobacteria for their growth. Several T-DNA genes stimulate or influence plant growth. Among these, iaaH and iaaM encode proteins involved in auxin synthesis, whereas ipt encodes a protein involved in cytokinin synthesis. Growth can also be induced or modified by other T-DNA genes, collectively called plast genes (for phenotypic plasticity). The plast genes are defined by their common ancestry and are mostly found on T-DNAs. They can influence plant growth in different ways, but the molecular basis of their morphogenetic activity remains largely unclear. Only some plast genes, such as 6b, rolB, rolC, and orf13, have been studied in detail. Plast genes have a significant potential for applied research and may be used to modify the growth of crop plants. In this review, I summarize the most important findings and models from 30 years of plast gene research and propose some outlooks for the future.
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Jin Y, Hu J, Liu X, Ruan Y, Sun C, Liu C. T- 6b allocates more assimilation product for oil synthesis and less for polysaccharide synthesis during the seed development of Arabidopsis thaliana. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:19. [PMID: 28127400 PMCID: PMC5251281 DOI: 10.1186/s13068-017-0706-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/10/2017] [Indexed: 06/01/2023]
Abstract
BACKGROUND As an Agrobacterium tumefaciens T-DNA oncogene, T-6b induces the development of tumors and the enation syndrome in vegetative tissues of transgenic plants. Most of these effects are related to increases in soluble sugar contents. To verify the potential roles of T-6b in the distribution of carbon in developing seeds, not in vegetative tissues, we fused an endosperm-specific promoter to the T-6b gene for expression in transgenic Arabidopsis thaliana plants. RESULTS The expression of T-6b in reproductive organs did not induce the development of the enation syndrome, and moreover, promoted endosperm expansion, which increased the total seed biomass by more than 10%. Additionally, T-6b also increased oil content in mature seeds by more than 10% accompanied with the decrease of starch and mucilage content at the same time. CONCLUSIONS T-6b enhances seed biomass and helps oil biosynthesis but not polysaccharides in reproductive organs without disturbing vegetative growth and development. Our findings suggest T-6b may be very useful for increasing oil production in biodiesel plants.
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Affiliation(s)
- Yunkai Jin
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, 410128 China
- Department of Plant Biology, Uppsala BioCenter, Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, PO Box 7080, SE-75007 Uppsala, Sweden
| | - Jia Hu
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, 410128 China
- Key Laboratory of Education, Department of Hunan Province on Plant Genetics and Molecular Biology, College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, 410128 China
| | - Xun Liu
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, 410128 China
- Key Laboratory of Education, Department of Hunan Province on Plant Genetics and Molecular Biology, College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, 410128 China
| | - Ying Ruan
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, 410128 China
- Key Laboratory of Education, Department of Hunan Province on Plant Genetics and Molecular Biology, College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha, 410128 China
| | - Chuanxin Sun
- Department of Plant Biology, Uppsala BioCenter, Linnean Center for Plant Biology, Swedish University of Agricultural Sciences, PO Box 7080, SE-75007 Uppsala, Sweden
| | - Chunlin Liu
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, 410128 China
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Chen K, Otten L. Natural Agrobacterium Transformants: Recent Results and Some Theoretical Considerations. FRONTIERS IN PLANT SCIENCE 2017; 8:1600. [PMID: 28966626 PMCID: PMC5606197 DOI: 10.3389/fpls.2017.01600] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 08/31/2017] [Indexed: 05/19/2023]
Abstract
Agrobacterium rhizogenes causes hairy root growth on a large number of plant species. It does so by transferring specific DNA fragments (T-DNA) from its root-inducing plasmid (pRi) into plant cells. Expression of T-DNA genes leads to abnormal root growth and production of specific metabolites (opines) which are taken up by the bacterium and used for its growth. Recent work has shown that several Nicotiana, Linaria, and Ipomoea species contain T-DNA genes from A. rhizogenes in their genomes. Plants carrying such T-DNAs (called cellular T-DNA or cT-DNA) can be considered as natural transformants. In the Nicotiana genus, seven different T-DNAs are found originating from different Agrobacterium strains, and in the Tomentosae section no <4 successive insertion events took place. In several cases cT-DNA genes were found to be expressed. In some Nicotiana tabacum cultivars the opine synthesis gene TB-mas2' is expressed in the roots. These cultivars were found to produce opines. Here we review what is known about natural Agrobacterium transformants, develop a theoretical framework to analyze this unusual phenomenon, and provide some outlines for further research.
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Affiliation(s)
- Ke Chen
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong UniversityShanghai, China
| | - Léon Otten
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique (CNRS)Strasbourg, France
- *Correspondence: Léon Otten
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Tepfer D. DNA Transfer to Plants by Agrobacterium rhizogenes: A Model for Genetic Communication Between Species and Biospheres. REFERENCE SERIES IN PHYTOCHEMISTRY 2017. [DOI: 10.1007/978-3-319-28669-3_19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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Chen K, Otten L. Morphological analysis of the 6b oncogene-induced enation syndrome. PLANTA 2016; 243:131-48. [PMID: 26353911 DOI: 10.1007/s00425-015-2387-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 08/14/2015] [Indexed: 06/05/2023]
Abstract
MAIN CONCLUSION The T-DNA 6b oncogene induces complex and partly unprecedented phenotypic changes in tobacco stems and leaves, which result from hypertrophy and hyperplasia with ectopic spot-like, ridge-like and sheet-like meristems. The Agrobacterium T-DNA oncogene 6b causes complex growth changes in tobacco including enations; this unusual phenotype has been called "6b enation syndrome". A detailed morphological and anatomical analysis of the aerial part of Nicotiana tabacum plants transformed with a dexamethasone-inducible dex-T-6b gene revealed several striking growth phenomena. Among these were: uniform growth of ectopic photosynthetic cells on the abaxial leaf side, gutter-like petioles with multiple parallel secondary veins, ectopic leaf primordia emerging behind large glandular trichomes, corniculate structures emerging from distal ends of secondary veins, pin-like structures with remarkable branching patterns, ectopic vascular strands in midveins and petioles extending down along the stem, epiascidia and hypoascidia, double enations and complete inhibition of leaf outgrowth. Ectopic stipule-like leaves and inverted leaves were found at the base of the petioles. Epinastic and hyponastic growth of petioles and midveins yielded complex but predictable leaf folding patterns. Detailed anatomical analysis of over sixty different 6b-induced morphological changes showed that the different modifications are derived from hypertrophy and abaxial hyperplasia, with ectopic photosynthetic cells forming spot-like, ridge-like and sheet-like meristems and ectopic vascular strands forming regular patterns in midveins, petioles and stems. Part of the enation syndrome is due to an unknown phloem-mobile enation factor. Graft experiments showed that the 6b mRNA is mobile and could be the enation factor. Our work provides a better insight in the basic effects of the 6b oncogene.
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Affiliation(s)
- Ke Chen
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084, Strasbourg, France
| | - Léon Otten
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084, Strasbourg, France.
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15
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Ito M, Machida Y. Reprogramming of plant cells induced by 6b oncoproteins from the plant pathogen Agrobacterium. JOURNAL OF PLANT RESEARCH 2015; 128:423-435. [PMID: 25694001 DOI: 10.1007/s10265-014-0694-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 11/25/2014] [Indexed: 06/04/2023]
Abstract
Reprogramming of plant cells is an event characterized by dedifferentiation, reacquisition of totipotency, and enhanced cell proliferation, and is typically observed during formation of the callus, which is dependent on plant hormones. The callus-like cell mass, called a crown gall tumor, is induced at the sites of infection by Agrobacterium species through the expression of hormone-synthesizing genes encoded in the T-DNA region, which probably involves a similar reprogramming process. One of the T-DNA genes, 6b, can also by itself induce reprogramming of differentiated cells to generate tumors and is therefore recognized as an oncogene acting in plant cells. The 6b genes belong to a group of Agrobacterium T-DNA genes, which include rolB, rolC, and orf13. These genes encode proteins with weakly conserved sequences and may be derived from a common evolutionary origin. Most of these members can modify plant growth and morphogenesis in various ways, in most cases without affecting the levels of plant hormones. Recent studies have suggested that the molecular function of 6b might be to modify the patterns of transcription in the host nuclei, particularly by directly targeting the host transcription factors or by changing the epigenetic status of the host chromatin through intrinsic histone chaperone activity. In light of the recent findings on zygotic resetting of nucleosomal histone variants in Arabidopsis thaliana, one attractive idea is that acquisition of totipotency might be facilitated by global changes of epigenetic status, which might be induced by replacement of histone variants in the zygote after fertilization and in differentiated cells upon stimulation by plant hormones as well as by expression of the 6b gene.
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Affiliation(s)
- Masaki Ito
- Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa-ku, Nagoya, 464-8601, Japan,
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16
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Chen K, Dorlhac de Borne F, Szegedi E, Otten L. Deep sequencing of the ancestral tobacco species Nicotiana tomentosiformis reveals multiple T-DNA inserts and a complex evolutionary history of natural transformation in the genus Nicotiana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 80:669-82. [PMID: 25219519 DOI: 10.1111/tpj.12661] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 07/30/2014] [Accepted: 08/29/2014] [Indexed: 05/21/2023]
Abstract
Nicotiana species carry cellular T-DNA sequences (cT-DNAs), acquired by Agrobacterium-mediated transformation. We characterized the cT-DNA sequences of the ancestral Nicotiana tabacum species Nicotiana tomentosiformis by deep sequencing. N. tomentosiformis contains four cT-DNA inserts derived from different Agrobacterium strains. Each has an incomplete inverted-repeat structure. TA is similar to part of the Agrobacterium rhizogenes 1724 mikimopine-type T-DNA, but has unusual orf14 and mis genes. TB carries a 1724 mikimopine-type orf14-mis fragment and a mannopine-agropine synthesis region (mas2-mas1-ags). The mas2' gene codes for an active enzyme. TC is similar to the left part of the A. rhizogenes A4 T-DNA, but also carries octopine synthase-like (ocl) and c-like genes normally found in A. tumefaciens. TD shows a complex rearrangement of T-DNA fragments similar to the right end of the A4 TL-DNA, and including an orf14-like gene and a gene with unknown function, orf511. The TA, TB, TC and TD insertion sites were identified by alignment with N. tabacum and Nicotiana sylvestris sequences. The divergence values for the TA, TB, TC and TD repeats provide an estimate for their relative introduction times. A large deletion has occurred in the central part of the N. tabacum cv. Basma/Xanthi TA region, and another deletion removed the complete TC region in N. tabacum. Nicotiana otophora lacks TA, TB and TD, but contains TC and another cT-DNA, TE. This analysis, together with that of Nicotiana glauca and other Nicotiana species, indicates multiple sequential insertions of cT-DNAs during the evolution of the genus Nicotiana.
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Affiliation(s)
- Ke Chen
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes du C. N. R. S., Rue du Général Zimmer 12, 67084, Strasbourg, France
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17
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Ishibashi N, Kitakura S, Terakura S, Machida C, Machida Y. Protein encoded by oncogene 6b from Agrobacterium tumefaciens has a reprogramming potential and histone chaperone-like activity. FRONTIERS IN PLANT SCIENCE 2014; 5:572. [PMID: 25389429 PMCID: PMC4211554 DOI: 10.3389/fpls.2014.00572] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 10/05/2014] [Indexed: 05/31/2023]
Abstract
Crown gall tumors are formed mainly by actions of a group of genes in the T-DNA that is transferred from Agrobacterium tumefaciens and integrated into the nuclear DNA of host plants. These genes encode enzymes for biosynthesis of auxin and cytokinin in plant cells. Gene 6b in the T-DNA affects tumor morphology and this gene alone is able to induce small tumors on certain plant species. In addition, unorganized calli are induced from leaf disks of tobacco that are incubated on phytohormone-free media; shooty teratomas, and morphologically abnormal plants, which might be due to enhanced competence of cell division and meristematic states, are regenerated from the calli. Thus, the 6b gene appears to stimulate a reprogramming process in plants. To uncover mechanisms behind this process, various approaches including the yeast-two-hybrid system have been exploited and histone H3 was identified as one of the proteins that interact with 6b. It has been also demonstrated that 6b acts as a histone H3 chaperon in vitro and affects the expression of various genes related to cell division competence and the maintenance of meristematic states. We discuss current views on a role of 6b protein in tumorigenesis and reprogramming in plants.
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Affiliation(s)
- Nanako Ishibashi
- Division of Biological Science, Graduate School of Science, Nagoya UniversityNagoya, Japan
| | - Saeko Kitakura
- Division of Biological Science, Graduate School of Science, Nagoya UniversityNagoya, Japan
- Graduate School of Bioscience and Biotechnology, Chubu UniversityKasugai, Japan
| | - Shinji Terakura
- Division of Biological Science, Graduate School of Science, Nagoya UniversityNagoya, Japan
| | - Chiyoko Machida
- Graduate School of Bioscience and Biotechnology, Chubu UniversityKasugai, Japan
| | - Yasunori Machida
- Division of Biological Science, Graduate School of Science, Nagoya UniversityNagoya, Japan
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18
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Wang JH, Lin HH, Liu CT, Lin TC, Liu LYD, Lee KT. Transcriptomic analysis reveals that reactive oxygen species and genes encoding lipid transfer protein are associated with tobacco hairy root growth and branch development. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:678-87. [PMID: 24625031 DOI: 10.1094/mpmi-12-13-0369-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The hairy root, a specialized plant tissue that emerges from a cell transformed with transfer DNA (T-DNA) from Agrobacterium rhizogenes, can be used to study root biology and utilized in biotechnological applications. The rol genes are known to participate in the generation of hairy roots; however, the means by which the rol genes contribute to the initiation and the maintenance of hairy roots remains largely unknown. We demonstrated that tobacco hairy roots lacking either rolB or rolC exhibited fewer branch roots and lost their growth ability in long-term subculture. Additionally, a microarray analysis revealed that the expression of several genes encoding lipid transfer proteins (LTP) and reactive oxygen species (ROS)-related genes was significantly suppressed in rolB- or rolC-deficient hairy roots. We found that hairy root clones that exhibited greater branching expressed higher levels of RolB or RolC and the genes encoding LTP identified from the microarray. When hairy roots were compared with intact roots, the expression levels of LTP-encoding genes were dramatically different. In addition, ROS were present at lower levels in rolB- and rolC-deficient hairy roots. We therefore suggest that upregulating LTP and increasing the level of ROS is important for hairy root growth.
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19
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20
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Bulgakov VP, Shkryl YN, Veremeichik GN, Gorpenchenko TY, Vereshchagina YV. Recent advances in the understanding of Agrobacterium rhizogenes-derived genes and their effects on stress resistance and plant metabolism. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2013; 134:1-22. [PMID: 23576052 DOI: 10.1007/10_2013_179] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
It is commonly accepted that the plant pathogens Agrobacterium rhizogenes and Agrobacterium tumefaciens, acting via their T-DNA oncogenes, disturb hormone metabolism or hormone perception pathways in plants, thereby attaining their aim of successful pathogenesis. In this work, we summarize recent data on the A. rhizogenes rolC and rolB oncogenes in comparison to the A. tumefaciens 6b oncogene with respect to their effects on the physiology of transformed cells. The newly discovered functions of the rol genes include the modulation of secondary metabolism, the modulation of levels of intracellular ROS and stress resistance of transformed cells, changed sucrose metabolism, and the inhibition of programmed cell death. We show that the rol genes do not have suppressive effects on plant innate immunity; rather, these genes activate plant defense reactions. The existence of not only the hormone-related mechanism of pathogenicity but also the defense-related mechanism of pathogenicity during plant-Agrobacterium interactions is suggested.
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Affiliation(s)
- Victor P Bulgakov
- Institute of Biology and Soil Science, Far East Branch of the Russian Academy of Sciences, Vladivostok, 690022, Russia,
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21
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Gorpenchenko TY, Aminin DL, Vereshchagina YV, Shkryl YN, Veremeichik GN, Tchernoded GK, Bulgakov VP. Can plant oncogenes inhibit programmed cell death? The rolB oncogene reduces apoptosis-like symptoms in transformed plant cells. PLANT SIGNALING & BEHAVIOR 2012; 7:1058-1061. [PMID: 22899080 PMCID: PMC3489626 DOI: 10.4161/psb.21123] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The rolB oncogene was previously identified as an important player in ROS metabolism in transformed plant cells. Numerous reports indicate a crucial role for animal oncogenes in apoptotic cell death. Whether plant oncogenes such as rolB can induce programmed cell death (PCD) in transformed plant cells is of particular importance. In this investigation, we used a single-cell assay based on confocal microscopy and fluorescent dyes capable of discriminating between apoptotic and necrotic cells. Our results indicate that the expression of rolB in plant cells was sufficient to decrease the proportion of apoptotic cells in steady-state conditions and diminish the rate of apoptotic cells during induced PCD. These data suggest that plant oncogenes, like animal oncogenes, may be involved in the processes mediating PCD.
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Affiliation(s)
- Tatiana Y. Gorpenchenko
- Institute of Biology and Soil Science; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
| | - Dmitry L. Aminin
- Pacific Institute of Bioorganic Chemistry; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
| | - Yuliya V. Vereshchagina
- Institute of Biology and Soil Science; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
| | - Yuri N. Shkryl
- Institute of Biology and Soil Science; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
| | - Galina N. Veremeichik
- Institute of Biology and Soil Science; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
| | - Galina K. Tchernoded
- Institute of Biology and Soil Science; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
| | - Victor P. Bulgakov
- Institute of Biology and Soil Science; Far East Branch of Russian Academy of Sciences; Vladivostok, Russia
- Far Eastern Federal University; Vladivostok, Russia
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22
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Bulgakov VP, Gorpenchenko TY, Veremeichik GN, Shkryl YN, Tchernoded GK, Bulgakov DV, Aminin DL, Zhuravlev YN. The rolB gene suppresses reactive oxygen species in transformed plant cells through the sustained activation of antioxidant defense. PLANT PHYSIOLOGY 2012; 158:1371-81. [PMID: 22271748 PMCID: PMC3291252 DOI: 10.1104/pp.111.191494] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 01/20/2012] [Indexed: 05/05/2023]
Abstract
The rolB (for rooting locus of Agrobacterium rhizogenes) oncogene has previously been identified as a key player in the formation of hairy roots during the plant-A. rhizogenes interaction. In this study, using single-cell assays based on confocal microscopy, we demonstrated reduced levels of reactive oxygen species (ROS) in rolB-expressing Rubia cordifolia, Panax ginseng, and Arabidopsis (Arabidopsis thaliana) cells. The expression of rolB was sufficient to inhibit excessive elevations of ROS induced by paraquat, menadione, and light stress and prevent cell death induced by chronic oxidative stress. In rolB-expressing cells, we detected the enhanced expression of antioxidant genes encoding cytosolic ascorbate peroxidase, catalase, and superoxide dismutase. We conclude that, similar to pathogenic determinants in other pathogenic bacteria, rolB suppresses ROS and plays a role not only in cell differentiation but also in ROS metabolism.
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Affiliation(s)
- Victor P Bulgakov
- Institute of Biology and Soil Science, Far East Branch of Russian Academy of Sciences, Vladivostok 690022, Russia.
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23
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Mohajjel-Shoja H, Clément B, Perot J, Alioua M, Otten L. Biological activity of the Agrobacterium rhizogenes-derived trolC gene of Nicotiana tabacum and its functional relation to other plast genes. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2011; 24:44-53. [PMID: 20822423 DOI: 10.1094/mpmi-06-10-0139] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Agrobacterium rhizogenes induces hairy roots through the activity of three essential T-DNA genes, rolA, rolB, and rolC, whereas the orf13 gene acts as an accessory root-inducing gene. rolB, rolC, and orf13 belong to the highly diverged plast gene family with remotely related representatives in the endomycorrhizal basidiomycete Laccaria bicolor. Nicotiana glauca and N. tabacum contain A. rhizogenes-derived T-DNAs with active plast genes. Here, we report on the properties of a rolC homolog in N. tabacum, trolC. Dexamethasone-inducible trolC and A4-rolC genes from A. rhizogenes A4 induce comparable, strong growth effects affecting all parts of the plants. Several have not been described earlier and were found to be very similar to the effects of the distantly related plast gene 6b. They include leaf chlorosis and starch accumulation, enations, increase of sucrose-dependent leaf disk expansion, growth of isolated roots on low-sucrose media, and stimulation of sucrose uptake by small root fragments. Collectively, our findings indicate that enhancement of sucrose uptake plays an important role in generating the complex 6b and rolC phenotypes and might be an ancestral property of the plast genes.
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Affiliation(s)
- Hanieh Mohajjel-Shoja
- Department of Molecular Mechanisms of Phenotypic Plasticity, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084 Strasbourg, France
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24
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Wang M, Soyano T, Machida S, Yang JY, Jung C, Chua NH, Yuan YA. Molecular insights into plant cell proliferation disturbance by Agrobacterium protein 6b. Genes Dev 2010; 25:64-76. [PMID: 21156810 DOI: 10.1101/gad.1985511] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Agrobacterium Ti plasmid (T-DNA) 6b proteins interact with many different host proteins implicated in plant cell proliferation. Here, we show that Arabidopsis plants overexpressing 6b display microRNA (miRNA) deficiency by directly targeting SERRATE and AGO1 via a specific loop fragment (residues 40-55). In addition, we report the crystal structures of Agrobacterium tumefaciens AK6b at 2.1 Å, Agrobacterium vitis AB6b at 1.65 Å, and Arabidopsis ADP ribosylation factor (ARF) at 1.8 Å. The 6b structure adopts an ADP-ribosylating toxin fold closely related to cholera toxin. In vitro ADP ribosylation analysis demonstrates that 6b represents a new toxin family, with Tyr 66, Thr 93, and Tyr 153 as the ADP ribosylation catalytic residues in the presence of Arabidopsis ARF and GTP. Our work provides molecular insights, suggesting that 6b regulates plant cell growth by the disturbance of the miRNA pathway through its ADP ribosylation activity.
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Affiliation(s)
- Meimei Wang
- Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
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25
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Nemoto K, Hara M, Suzuki M, Seki H, Oka A, Muranaka T, Mano Y. Function of the aux and rol genes of the Ri plasmid in plant cell division in vitro. PLANT SIGNALING & BEHAVIOR 2009; 4:1145-7. [PMID: 20514230 PMCID: PMC2819440 DOI: 10.4161/psb.4.12.9904] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Accepted: 08/25/2009] [Indexed: 05/18/2023]
Abstract
Auxin-autonomous growth in vitro may be related to the integration and expression of the aux and rol genes from the root-inducing (Ri) plasmid in plant cells infected by agropine-type Agrobacterium rhizogenes. To elucidate the functions of the aux and rol genes in plant cell division, plant cell lines transformed with the aux1 and aux2 genes or with the rolABCD genes were established using tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells. The introduction of the aux1 and aux2 genes enabled the auxin-autonomous growth of BY-2 cells, but the introduction of the rolABCD genes did not affect the auxin requirement of the BY-2 cells. The results clearly show that the aux genes are necessary for auxinautotrophic cell division, and that the rolABCD genes are irrelevant in auxin autotrophy.
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Affiliation(s)
- Keiichirou Nemoto
- Graduate School of Bioscience; Tokai University, Numazu, Shizuoka Japan
| | - Masamitsu Hara
- Department of Biological Science and Technology; Tokai University, Numazu, Shizuoka Japan
| | | | - Hikaru Seki
- RIKEN Plant Science Center, Yokohama, Kanagawa Japan
| | - Atsuhiro Oka
- Institute for Chemical Research; Kyoto University, Uji, Kyoto Japan
| | - Toshiya Muranaka
- RIKEN Plant Science Center, Yokohama, Kanagawa Japan
- Plant Biotechnology Division; Yokohama City University, Yokohama, Kanagawa Japan
| | - Yoshihiro Mano
- Graduate School of Bioscience; Tokai University, Numazu, Shizuoka Japan
- Department of Biological Science and Technology; Tokai University, Numazu, Shizuoka Japan
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26
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Kitakura S, Terakura S, Yoshioka Y, Machida C, Machida Y. Interaction between Agrobacterium tumefaciens oncoprotein 6b and a tobacco nucleolar protein that is homologous to TNP1 encoded by a transposable element of Antirrhinum majus. JOURNAL OF PLANT RESEARCH 2008; 121:425-33. [PMID: 18463947 DOI: 10.1007/s10265-008-0160-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Accepted: 03/12/2008] [Indexed: 05/26/2023]
Abstract
When gene 6b on the T-DNA of Agrobacterium tumefaciens is transferred to plant cells, its expression causes plant hormone-independent division of cells in in vitro culture and abnormal cell growth, which induces various morphological defects in 6b-expressing transgenic Arabidopsis thaliana and Nicotiana tabacum plants. Protein 6b localizes to the nuclei, a requirement for the abnormal cell growth, and binds to a tobacco nuclear protein called NtSIP1 and histone H3. In addition, 6b has histone chaperone-like activity in vitro and affects the expression of various plant genes, including cell division-related genes and meristem-related class 1 KNOX homeobox genes, in transgenic Arabidopsis. Here, we report that 6b binds to a newly identified protein NtSIP2, whose amino acid sequence is predicted to be 30% identical and 51% similar to that of the TNP1 protein encoded by the transposon Tam1 of Antirrhinum majus. Immunolocalization analysis using anti-T7 antibodies showed nucleolar localization of most of the T7 epitope-tagged NtSIP2 proteins. A similar analysis with the T7-tagged 6b protein also showed subnucleolar as well as nuclear localization of the 6b protein. These results suggest the involvement of 6b along with NtSIP2 in certain molecular processes in the nucleolus as well as the nucleoplasm.
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Affiliation(s)
- Saeko Kitakura
- College of Bioscience and Biotechnology, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan
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27
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Terakura S, Ueno Y, Tagami H, Kitakura S, Machida C, Wabiko H, Aiba H, Otten L, Tsukagoshi H, Nakamura K, Machida Y. An oncoprotein from the plant pathogen agrobacterium has histone chaperone-like activity. THE PLANT CELL 2007; 19:2855-65. [PMID: 17890376 PMCID: PMC2048699 DOI: 10.1105/tpc.106.049551] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2006] [Revised: 08/23/2007] [Accepted: 08/27/2007] [Indexed: 05/17/2023]
Abstract
Protein 6b, encoded by T-DNA from the pathogen Agrobacterium tumefaciens, stimulates the plant hormone-independent division of cells in culture in vitro and induces aberrant cell growth and the ectopic expression of various genes, including genes related to cell division and meristem-related class 1 KNOX homeobox genes, in 6b-expressing transgenic Arabidopsis thaliana and Nicotiana tabacum plants. Protein 6b is found in nuclei and binds to several plant nuclear proteins. Here, we report that 6b binds specifically to histone H3 in vitro but not to other core histones. Analysis by bimolecular fluorescence complementation revealed an interaction in vivo between 6b and histone H3. We recovered 6b from a chromatin fraction from 6b-expressing plant cells. A supercoiling assay and digestion with micrococcal nuclease indicated that 6b acts as a histone chaperone with the ability to mediate formation of nucleosomes in vitro. Mutant 6b, lacking the C-terminal region that is required for cell division-stimulating activity and interaction with histone H3, was deficient in histone chaperone activity. Our results suggest a relationship between alterations in nucleosome structure and the expression of growth-regulating genes on the one hand and the induction of aberrant cell proliferation on the other.
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Affiliation(s)
- Shinji Terakura
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Aichi, Japan
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Clément B, Perot J, Geoffroy P, Legrand M, Zon J, Otten L. Abnormal accumulation of sugars and phenolics in tobacco roots expressing the Agrobacterium T-6b oncogene and the role of these compounds in 6b-induced growth. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2007; 20:53-62. [PMID: 17249422 DOI: 10.1094/mpmi-20-0053] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The Agrobacterium T-DNA oncogene 6b induces tumors and modifies the growth of transgenic plants by an unknown mechanism. We have investigated changes in roots of tobacco seedlings that express a dexamethasone-inducible T-6b (dex-T-6b) gene. On induction medium with sucrose, intact or isolated dex-T-6b roots accumulated sucrose, glucose, and fructose and changed their growth, contrary to noninduced roots. Root fragments bridging agar blocks with or without sucrose accumulated sugars at the site of sucrose uptake, resulting in local growth. Induced root fragments showed enhanced uptake of 14C-labeled sucrose, glucose, and fructose. When seedlings were placed on sucrose-free induction medium, sugar levels strongly decreased in roots and increased in cotyledons. Collectively, these results demonstrate that 6b stimulates sugar uptake and retention with drastic effects on growth. Apart from sugars, phenolic compounds also have been found to accumulate in 6b tissues and have been proposed earlier to play a role in 6b-induced growth. Induced dex-T-6b roots accumulated high levels of 5-caffeoylquinic acid (or chlorogenic acid [CGA]), but only under conditions where endogenous sugars increased. Inhibition of phenylalanine ammonia-lyase with the competitive inhibitor 2-aminoindan-2-phosphonic acid (AIP) abolished CGA accumulation without modifying sugar accumulation or affecting the 6b phenotype. We conclude that the absorption, retention, and abnormal accumulation of sugars are essential factors in 6b-induced growth changes, whereas phenylpropanoids only marginally contribute to the 6b seedling phenotype.
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Affiliation(s)
- Bernadette Clément
- Department of Cell Biology, Plant Molecular Biology Institute of the C. N. R. S., Rue du Général Zimmer 12, Strasbourg 67084, France
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Clément B, Pollmann S, Weiler E, Urbanczyk-Wochniak E, Otten L. The Agrobacterium vitis T-6b oncoprotein induces auxin-independent cell expansion in tobacco. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 45:1017-27. [PMID: 16507091 DOI: 10.1111/j.1365-313x.2006.02663.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Among the Agrobacterium T-DNA genes, rolB, rolC, orf13, orf8, lso, 6b and several other genes encode weakly homologous proteins with remarkable effects on plant growth. The 6b oncogene induces tumors and enations. In order to study its properties we have used transgenic tobacco plants that carry a dexamethasone-inducible 6b gene, dex-T-6b. Upon induction, dex-T-6b plants develop a large array of morphological modifications, some of which involve abnormal cell expansion. In the present investigation, dex-T-6b-induced expansion was studied in intact leaves and an in vitro leaf disc system. Although T-6b and indole-3-acetic acid (IAA) both induced expansion and were non-additive, T-6b expression did not increase IAA levels, nor did it induce an IAA-responsive gene. Fusicoccin (FC) is known to stimulate expansion by increasing cell wall plasticity. T-6b- and FC-induced expansion were additive at saturating FC concentrations, indicating that T-6b does not act by a similar mechanism to FC. T-6b expression led to higher leaf osmolality values, in contrast to FC, suggesting that the T-6b gene induces expansion by increasing osmolyte concentrations. Metabolite profiling showed that glucose and fructose played a major role in this increase. We infer that T-6b disrupts the osmoregulatory controls that govern cell expansion during development and wound healing.
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Affiliation(s)
- Bernadette Clément
- Department of Cell Biology, Institut de Biologie Moléculaire des Plantes, Rue du Général Zimmer 12, 67084 Strasbourg, France
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Umber M, Clément B, Otten L. The T-DNA oncogene A4-orf8 from Agrobacterium rhizogenes A4 induces abnormal growth in tobacco. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2005; 18:205-11. [PMID: 15782634 DOI: 10.1094/mpmi-18-0205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The related orf8 and iaaM T-DNA genes from Agrobacterium are each composed of two distinct parts. The 5' parts (called Norf8 or NiaaM) encode a 200-amino-acid (aa) sequence with homology to various T-DNA oncoproteins such as RolB, RolC, and 6b. The 3' parts (Corf8 or CiaaM) encode a 550-aa sequence with homology to IaaM proteins from Pseudomonas and Pantoea spp. Whereas iaaM genes encode flavin adenine dinucleotide (FAD)-dependent tryptophan 2-monooxygenases that catalyze the synthesis of indole-3-acetamide (IAM), A4-orf8 from Agrobacterium rhizogenes A4 does not. Plants expressing a 2x35S-A4-Norf8 construct accumulate soluble sugars and starch. We now have regenerated plants that express the full-size 2x35S-A4-orf8 and the truncated 2x35S-A4-Corf8 gene. 2x35S-A4-Corf8 plants accumulate starch and show reduced growth like 2x35S-A4-Norf8 plants but, in addition, display a novel set of characteristic growth modifications. These consist of leaf hypertrophy and hyperplasia (blisters); thick, dark-green leaves; thick stems; and swollen midveins. Mutations in the putative FAD-binding site of A4-Orf8 did not affect the blister syndrome. Plants expressing 2x35S-A4-Corf8 had a normal phenotype but contained less starch and soluble sugars than did wild-type plants. When 2x35S-A4-Corf8 plants were crossed to starch-accumulating 2x35S-A4-Norf8 plants with reduced growth, A4-Corf8 partially restored growth and reduced starch accumulation. A4-Corf8xA4-Norf8 crosses did not lead to the blister syndrome, suggesting that this requires physical linkage of the A4-NOrf8 and A4-COrf8 sequences.
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Affiliation(s)
- Marie Umber
- Institut de Biologie Moléculaire des Plantes, CNRS UPR2357, Rue du Géneral Zimmer 12, 67084 Strasbourg, France
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Udagawa M, Aoki S, Syono K. Expression analysis of the NgORF13 promoter during the development of tobacco genetic tumors. PLANT & CELL PHYSIOLOGY 2004; 45:1023-31. [PMID: 15356328 DOI: 10.1093/pcp/pch123] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We investigated the expression pattern of the promoter of Nicotiana glauca (Ng) ORF13 in the hybrids between N. glauca and N. langsdorffii harboring the NgORF13-beta-glucuronidase (GUS) chimeric gene. The promoter of NgORF13 of N. glauca had lower activities than the promoter of RiORF13 of Agrobacterium rhizogenes agropine-type root-inducing (Ri) plasmid. However, the localization of GUS activity in the NgORF13 transgenic plants was similar to that in the RiORF13 transgenic plants. The GUS activity of NgORF13-GUS was high in genetic tumors cultured in vitro or developed spontaneously on F1 plants with aging or by wounding. The GUS activity in tumors was observed in bud primordia, vascular bundles and leaves in the buds. While the activity was lower than in tumors, NgORF13-GUS was also expressed in vascular bundles and the parenchymatous tissues in plants regenerated from tumors. Furthermore, the promoter activity of NgORF13 was induced by wounding and activated by exogenous application of methyl jasmonate. During tumorization, NgORF13 was induced at an early stage and showed expression patterns similar to both NgrolB and NgrolC whose expression were investigated by Nagata et al. (1996) Plant Cell Physiol. 37: 489-498. It is thought that Ngrol genes might be involved in the formation of genetic tumors, and, moreover, NgORF13 might work in cooperation with NgrolB and NgrolC.
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Affiliation(s)
- Makiko Udagawa
- Faculty of Science, Japan Women's University, Bunkyo-ku, Tokyo, 112-8681 Japan.
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Moriuchi H, Okamoto C, Nishihama R, Yamashita I, Machida Y, Tanaka N. Nuclear localization and interaction of RolB with plant 14-3-3 proteins correlates with induction of adventitious roots by the oncogene rolB. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2004; 38:260-75. [PMID: 15078329 DOI: 10.1111/j.1365-313x.2004.02041.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The rooting-locus gene B (rolB) on the T-DNA of the root-inducing (Ri) plasmid in Agrobacterium rhizogenes is responsible for the induction of transformed adventitious roots, although the root induction mechanism is unknown. We report here that the RolB protein of pRi1724 (1724RolB) is associated with Nicotianatabacum14-3-3-like protein omegaII (Nt14-3-3 omegaII) in tobacco bright yellow (BY)-2 cells. Nt14-3-3 omegaII directly interacts with 1724RolB protein. Green fluorescent protein (GFP)-fused 1724RolB is localized to the nucleus. GFP-fused mutant 1724RolB proteins having a deletion or amino acid substitution are unable to interact with Nt14-3-3 omegaII and also show impaired nuclear localization. Moreover, these 1724RolB mutants show decreased capacity for adventitious root induction. These results suggest that adventitious root induction by 1724RolB protein correlates with its interaction with Nt14-3-3 omegaII and the nuclear localization of 1724RolB protein.
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Affiliation(s)
- Hiroshi Moriuchi
- Center for Gene Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan
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Grémillon L, Helfer A, Clément B, Otten L. New plant growth-modifying properties of the Agrobacterium T-6b oncogene revealed by the use of a dexamethasone-inducible promoter. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2004; 37:218-28. [PMID: 14690506 DOI: 10.1046/j.1365-313x.2003.01956.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Agrobacterium 6b oncogenes induce tumours on Nicotiana glauca and enations and associated modifications in transgenic N. tabacum plants. 2x35S-AB-6b tobacco rootstocks produced a graft-transmissible factor that induced enations in wild-type scions; the nature of this enation factor remains to be identified. Here, we report on the properties of tobacco plants carrying a dexamethasone-inducible T-6b gene (dex-T-6b). Induction with dex led to complex growth modifications, many of which have not been reported previously. Modifications were only found in growing tissues; mature tissues remained unaffected. Growth could be either stimulated or inhibited. Dex induction of young plants led to morphogenetic gradients that included enations, tubular leaves and fragmented leaf primordia. Root elongation was increased or slowed down, while radial root growth was strongly enhanced. Additional cell divisions were found in the root pericycle and vasculature. Enation factor import from mature tissues did not have the same effects on growing tissues as local T-6b synthesis: normal scions grafted on induced dex-T-6b rootstocks formed enations, whereas local dex-T-6b induction at the shoot apex led to numerous dark-green spots on the abaxial side of the leaves. In leaf patch assays, the 23-kDa T-6b protein was found to move through leaves and to enter the vascular system. This and the fact that rootstocks of spontaneous tobacco enation mutants did not modify wild-type scions contrary to 6b plants indicate that the 6b protein might be the enation factor.
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Affiliation(s)
- Louis Grémillon
- Institut de Biologie Moléculaire des Plantes, CNRS UPR2357, Rue du Général Zimmer 12, 67084 Strasbourg, France
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Umber M, Voll L, Weber A, Michler P, Otten L. The rolB-like part of the Agrobacterium rhizogenes orf8 gene inhibits sucrose export in tobacco. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2002; 15:956-62. [PMID: 12236602 DOI: 10.1094/mpmi.2002.15.9.956] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Many Agrobacterium T-DNA genes belong to the highly diverse rolB family. The mode of action of most of these genes is still unknown. rolB-like sequences also are present at the 5' ends of the T-DNA-located iaaM genes and the iaaM homolog orf8, whereas iaaM genes from Pseudomonas and Erwinia spp. lack such sequences. iaaM genes encode tryptophan monooxygenases; these enzymes convert tryptophan into indole-3-acetamide, a precursor of indole-3-acetic acid. Tobacco plants expressing the rolB-like part of the A4 orf8 gene (2x35S-A4-Norf8 plants) accumulate glucose, fructose, sucrose, and starch and resemble sucrose transporter (NtSUT1) antisense plants. Different lines of evidence indicate that 2x35S-A4-Norf8 plants export less sucrose from source leaves. Glucose, fructose, sucrose, and starch accumulate in source leaves during sink-source transition, whereas sink tissues like petioles and midveins contain lower levels than normal. Petiole exudation experiments demonstrate a significant decrease in export of label after 14C-sucrose infiltration and after 14CO2 labeling. Grafting of stunted homozygous 2x35S-A4-Norf8 plants onto wild-type rootstocks restores growth, indicating that unloading is not affected. Growth of 2x35S-A4-Norf8 seedlings is inhibited on naphthalene acetic acid-containing media, suggesting a link between sucrose transport and auxin sensitivity.
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Affiliation(s)
- Marie Umber
- Institut de Biologie Moléculaire des Plantes, CNRS UPR2357, Strasbourg, France
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Gális I, Simek P, Van Onckelen HA, Kakiuchi Y, Wabiko H. Resistance of transgenic tobacco seedlings expressing the Agrobacterium tumefaciens C58-6b gene, to growth-inhibitory levels of cytokinin is associated with elevated IAA levels and activation of phenylpropanoid metabolism. PLANT & CELL PHYSIOLOGY 2002; 43:939-50. [PMID: 12198197 DOI: 10.1093/pcp/pcf112] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
We previously reported that the Agrobacterium tumefaciens C58-6b gene confers resistance to growth-inhibitory levels of exogenously applied N(6)-benzyladenine (BA, cytokinin) in transgenic tobacco (Nicotiana tabacum) seedlings. Here, we found that intracellular levels of indoleacetic acid (IAA, auxin) increased in transgenics but declined in wild-type seedlings upon BA treatment. Since exogenously supplied 1-naphthalene acetic acid (NAA), a stable synthetic auxin, counteracted the growth inhibition of wild-type seedlings by BA, we suggest that BA-induced growth inhibition in wild-type seedlings occurs, at least in part, as a result of intracellular IAA deficiency. Further HPLC analysis of cell extracts from BA-treated seedlings revealed that a fluorescent compound, later identified as the phenylpropanoid, scopolin, and the major phenolic compound, chlorogenic acid, accumulated earlier in transgenics than in wild-type seedlings. Gene transcripts encoding phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, and 4-coumarate:CoA ligase, which are responsible for the early steps of phenylpropanoid biosynthesis, accumulated earlier and to higher levels in transgenics than in wild-type seedlings as determined by Northern hybridization analysis, thus accounting for the early accumulation of scopolin and chlorogenic acid in transgenics. As some phenolic compounds, including chlorogenic acid and scopoletin (aglycon of scopolin) are suggested to inhibit IAA catabolism, we further propose that C58-6b gene expression protects IAA from degradation by inducing the early phenylpropanoid pathway.
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Affiliation(s)
- Ivan Gális
- Biotechnology Institute, Akita Prefectural University, 2-2 Minami, Ohgata, Akita, 010-0444 Japan
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Otten L, Helfer A. Biological activity of the rolB-like 5' end of the A4-orf8 gene from the Agrobacterium rhizogenes TL-DNA. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2001; 14:405-11. [PMID: 11277438 DOI: 10.1094/mpmi.2001.14.3.405] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The iaaM gene from different plant-associated bacteria encodes a tryptophan monooxygenase (IaaM) that catalyzes the synthesis of indole-3-acetamide (IAM), a precursor of indole-3-acetic acid (IAA). Unlike the IaaM proteins from other bacteria, Agrobacterium spp. T-DNA-encoded IaaM proteins carry a 200 amino acid N-terminal extension with low homology to various members of the RolB protein family. This family is composed of 18 highly divergent T-DNA-encoded proteins, the basic functions of which are still largely undetermined. Deletion of the 5' rolB-like extension of the iaaM gene from Agrobacterium tumefaciens strain Ach5 did not lead to a reduction in IAM synthesis in plants. When expressed in tobacco, the rolB-like fragment did not affect growth or morphology. An iaaM homolog (A4-orf8) from the TL-DNA of Agrobacterium rhizogenes strain A4 also was investigated. Neither the full-size A4-orf8 gene nor the 5'-truncated form induced detectable IAM synthesis. Plants expressing the rolB-like part of the A4-orf8 gene, however, were dwarfed and mottled to various extents and synthesized abnormally high amounts of glucose, fructose, sucrose, and starch.
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Affiliation(s)
- L Otten
- Department of Cell Biology, Plant Molecular Biology Institute of the CNRS, Strasbourg, France.
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Lemcke K, Prinsen E, van Onckelen H, Schmülling T. The ORF8 gene product of Agrobacterium rhizogenes TL-DNA has tryptophan 2-monooxygenase activity. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2000; 13:787-790. [PMID: 10875340 DOI: 10.1094/mpmi.2000.13.7.787] [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 open reading frame 8 (ORF8) is located on the TL-DNA of the phytopathogenic soil bacterium Agrobacterium rhizogenes strain A4. The predicted ORF8 protein has a particular structure and is possibly a natural fusion protein. The N-terminal domain shows homology to the A. rhizogenes rolB protein and may modulate the auxin responsiveness of host cells. The C terminus has up to 38% homology to tryptophan 2-monooxygenases (t2m). We show that ORF8 overexpressing plants contain a fivefold higher concentration of indole-3-acetamide (IAM) than untransformed plants. Protein extracts from seedlings and Escherichia coli overexpressing ORF8 show significantly higher turnover rates of tryptophan to IAM than negative controls. We conclude that the ORF8 gene product has tryptophan 2-monooxygenase activity.
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Affiliation(s)
- K Lemcke
- Zentrum für Molekularbiologie der Pflanzen, Allgemeine Genetik, University of Tübingen, Germany
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Levesque H, Lepingle A, Nicaud JM, Gaillardin C. Sequencing of a 9·2 kb telomeric fragment from the right arm of Saccharomyces cerevisiae chromosome XIV. Yeast 1998. [DOI: 10.1002/(sici)1097-0061(19960315)12:3<289::aid-yea909>3.0.co;2-m] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Limami, Sun, Douat, Helgeson, Tepfer. Natural genetic transformation by agrobacterium rhizogenes . Annual flowering in two biennials, belgian endive and carrot. PLANT PHYSIOLOGY 1998; 118:543-50. [PMID: 9765539 PMCID: PMC34829 DOI: 10.1104/pp.118.2.543] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/1998] [Accepted: 07/09/1998] [Indexed: 05/08/2023]
Abstract
Genetic transformation of Belgian endive (Cichorium intybus) and carrot (Daucus carota) by Agrobacterium rhizogenes resulted in a transformed phenotype, including annual flowering. Back-crossing of transformed (R1) endive plants produced a line that retained annual flowering in the absence of the other traits associated with A. rhizogenes transformation. Annualism was correlated with the segregation of a truncated transferred DNA (T-DNA) insertion. During vegetative growth, carbohydrate reserves accumulated normally in these annuals, and they were properly mobilized prior to anthesis. The effects of individual root-inducing left-hand T-DNA genes on flowering were tested in carrot, in which rolC (root locus) was the primary promoter of annualism and rolD caused extreme dwarfism. We discuss the possible adaptive significance of this attenuation of the phenotypic effects of root-inducing left-hand T-DNA.
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Affiliation(s)
- Limami
- Institut National de la Recherche Agronomique, Federation Nationale de Producteurs d'Endive and Laboratoire du Metabolisme et de la Nutrition des Plantes, Institut National de la Recherche Agronomique, 78026, Versailles, cedex, France
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40
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Vilaine F, Rembur J, Chriqui D, Tepfer M. Modified development in transgenic tobacco plants expressing a rolA::GUS translational fusion and subcellular localization of the fusion protein. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 1998; 11:855-9. [PMID: 9725017 DOI: 10.1094/mpmi.1998.11.9.855] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The rolA gene is transferred naturally by Agrobacterium rhizogenes to the genome of host plants, where it induces dramatic changes in development of transformed plants, including dwarfism and leaf wrinkling. The predicted translation product of the rolA gene is a small (11.4 kDa), basic (pI = 11.2) protein, which has no clearly significant similarity to sequences in the data bases. We have introduced into the tobacco genome a gene encoding a rolA::GUS fusion protein. Expression of this gene led to synthesis of an RNA and a protein of expected size, and the transformed plants exhibited the dwarfism and leaf wrinkling typical of rolA plants, but to a lesser degree than plants transformed with the wild-type rolA gene. The distribution of beta-glucuronidase (GUS) activity was compared in subcellular fractions of leaf extracts from plants expressing either the rolA::gus gene or a control gus construct. As expected, in the control plants, GUS activity was essentially cytosolic. In contrast, in plants expressing the rolA::gus gene the highest specific activity was associated with the plasmalemma fraction.
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Affiliation(s)
- F Vilaine
- Laboratorie de Biologie Cellulaire, INRA-Centre de Versailles, France
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41
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Lemcke K, Schmülling T. Gain of function assays identify non-rol genes from Agrobacterium rhizogenes TL-DNA that alter plant morphogenesis or hormone sensitivity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1998; 15:423-33. [PMID: 9750353 DOI: 10.1046/j.1365-313x.1998.00223.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This study tested the morphogenetic potential of 15 open reading frames of the TL-DNA of Agrobacterium rhizogenes strain HRI. These open reading frames were expressed individually under the control of the 35S RNA promoter in transgenic tobacco plants (Nicotiana tabacum L.). Expression of three T-DNA loci, ORF3n, ORF8 and ORF13, alters plant morphogenesis or the response of transgenic tissues to plant hormones. ORF3n transgenic plants are characterized by retarded flowering, altered internode elongation, altered leaf shape and, in particular, leaf tip necrosis. ORF3n and ORF8 expression reduces the sensitivity to auxin and cytokinin in combination or auxin alone. Tetracycline-dependent expression of ORF13 overcomes a selection of low levels of expression during plant regeneration and reveals a strong inhibitory effect of the ORF13 gene product on cell division and cell elongation. We conclude that the A. rhizogenes TL-DNA harbors genetic information that is important for pathogenicity apart from the well studied rol genes. We propose that these genes play mainly a negative regulatory role during pathogenesis. Moreover, these loci might be relevant to successful infections in specific host plants.
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Affiliation(s)
- K Lemcke
- Universität Tübingen, Allgemeine Genetik, Germany
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42
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Otten L, Schmidt J. A T-DNA from the Agrobacterium tumefaciens limited-host-range strain AB2/73 contains a single oncogene. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 1998; 11:335-342. [PMID: 9574502 DOI: 10.1094/mpmi.1998.11.5.335] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Agrobacterium tumefaciens strain AB2/73 isolated from Lippia canescens has been described as a limited-host-range strain. Its tumor-inducing (Ti) plasmid has been found to lack DNA homology to known T-DNAs (L. Unger, S. F. Ziegler, G. A. Huffman, V. C. Knauf, R. Peet, L. W. Moore, M. P. Gordon, and E. W. Nester. J. Bacteriol. 164:723-730, 1985). We have isolated a T-DNA from AB2/73 by using a heterologous border sequence as a probe. The AB2/73 T-DNA sequence (3,504 bp) is flanked by canonical border sequences, has no detectable DNA homology with other T-DNAs, and contains only two genes: lsn (Lippia strain nopaline synthaselike gene) and lso (Lippia strain oncogene). The lso gene induces nondifferentiating tumors on a limited number of hosts when transferred by a Ti plasmid from a wide-host-range strain. Part of the predicted Lso protein is weakly homologous to other Agrobacterium oncoproteins encoded by rolB, rolB, orf13, gene e, gene 5, and gene 3'. A 28-kb fragment corresponding to the virA to virE region was cloned by using a heterologous vir fragment as probe. The AB2/73 vir region is homologous to most of the C58 virulence region; however, the virA gene is most related to the virA gene of the Agrobacterium vitis limited-host-range strain Ag162.
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Affiliation(s)
- L Otten
- Department of Cell Biology, Plant Molecular Biology Institute of the C.N.R.S., Strasbourg, France.
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Levesque H, Lepingle A, Nicaud JM, Gaillardin C. Sequencing of a 9.2 kb telomeric fragment from the right arm of Saccharomyces cerevisiae chromosome XIV. Yeast 1996; 12:289-95. [PMID: 8904342 DOI: 10.1002/(sici)1097-0061(19960315)12:3%3c289::aid-yea909%3e3.0.co;2-m] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We report the complete sequence of a 9.2 kb fragment next to and including the right telomere of Saccharomyces cerevisiae chromosome XIV. Four open reading frames (ORFs) longer than 100 amino acids were observed in the sequenced segment. One ORF (378 codons) does not show any significant homology with proteins in the databases and corresponds to a putative new gene. Two ORFs are almost identical to the known YCR007/YKL219 and PAU1-like hypothetical protein families already identified on several S. cerevisiae chromosomes. These ORFs, whose function is unknown, are generally associated with sub-telomeric regions of chromosomes. The fourth one shows significant identities with bacterial mannitol dehydrogenases. It could be a yeast gene implicated in the metabolism of mannitol (or a related substrate). The sequence has been deposited in the EMBL data library under Accession Number X86790.
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Affiliation(s)
- H Levesque
- Institut National Agronomique Paris-Grignon, Laboratoire de Genetique Moleculaire et Cellulaire, France
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Guivarc'h A, Carneiro M, Vilaine F, Pautot V, Chriqui D. Tissue-specific expression of the rolA gene mediates morphological changes in transgenic tobacco. PLANT MOLECULAR BIOLOGY 1996; 30:125-34. [PMID: 8616229 DOI: 10.1007/bf00017807] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The spatial and temporal activity of the entire and individual promoter domains of the rolA gene of Agrobacterium rhizogenes was investigated and correlated with the distinctive features of the phenotypes of transgenic tobacco plants. The GUS assay was performed in the presence of an oxidative catalyst during the development of transgenic plants expressing chimeric genes containing the beta-glucuronidase coding sequence under the control of the different promoter domains. In situ hybridization was also used on transgenic plants harbouring rolA under the control of the entire or deleted promoter. This paper demonstrates for the first time that the entire rolA promoter, composed of domains, A, B and C, is silent in seeds, then activated at the onset of germination in the cotyledons and in the elongation zone of the radicle and is finally expressed throughout the vegetative and floral phases. Domains B + C, which were sufficient to induce wrinkled leaves and short internodes, were active in all the stem tissues, but only in the companion cells of the phloem strands of the leaves. Domain C, which specified a dwarf phenotype with normal leaves, was weakly expressed in the stem vascular bundles and in the leaf internal phloem. These results indicate that the vascular bundles are the primary targets for the generation of the short internode phenotype. Furthermore, the local expression of rolA in the stem vascular bundles induced a size reduction of the surrounding parenchyma cells, suggesting the existence of some diffusible factor(s) associated with the expression of the rolA gene.
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Affiliation(s)
- A Guivarc'h
- Laboratoire CEMV, Université Pierre et Marie Curie, Paris, France
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Elmayan T, Tepfer M. Evaluation in tobacco of the organ specificity and strength of the rolD promoter, domain A of the 35S promoter and the 35S2 promoter. Transgenic Res 1995; 4:388-96. [PMID: 7581519 DOI: 10.1007/bf01973757] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In order to study the expression in plants of the rolD promoter of Agrobacterium rhizogenes, we have constructed chimaeric genes placing the coding region of the gusA (uidA) marker gene under control of two rolD promoter fragments of different length. Similar results were obtained with both genes. Expression studies were carried out in transformed R1 progeny plants. In mature transformed tobacco plants, the rolD-gus genes were expressed strongly in roots, and to much lower levels in stems and leaves. This pattern of expression was transmitted to progeny, though the ratio of the level of expression in roots relative to that in leaves was much lower in young seedlings. The degree of root specificity in rolD-gus transformants was less than that of a gene constructed with domain A of the CaMV 35S promoter, domA-gus, but the level of root expression was much higher than with the latter gene. However, the level of expression of the rolD-gus genes was less than that of a gus gene with a 35S promoter with doubled domain B, 35S2-gus. The rolD-gus genes had a distinctive pattern of expression in roots, compared to that of the two other genes, with the strongest GUS activity observed in the root elongation zone and in vascular tissue, and much less in the root apex.
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Affiliation(s)
- T Elmayan
- Laboratoire de Biologie Cellulaire, INRA-Versailles, France
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Broer I, Dröge-Laser W, Barker RF, Neumann K, Klipp W, Pühler A. Identification of the Agrobacterium tumefaciens C58 T-DNA genes e and f and their impact on crown gall tumour formation. PLANT MOLECULAR BIOLOGY 1995; 27:41-57. [PMID: 7865795 DOI: 10.1007/bf00019177] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
DNA sequence analysis of the 4.4 kilobases (kb) Eco RI fragment 14 from T-DNA of Agrobacterium tumefaciens C58 revealed three open reading frames. One of them (945 bp) was supposed to encode the transcript e, the function of which has not been identified to date. Furthermore, a so far undescribed open reading frame (1035 bp) was identified, located in the centre of the Eco RI fragment 14 and termed gene f. The third open reading frame encoded the carboxy-terminal part of the agrocinopine synthase (Acs). The gene e-encoded protein showed significant homologies to the gene products of the Agrobacterium rhizogenes rolB gene and the Agrobacterium tumefaciens gene 5. Both gene products are supposed to regulate the plant's reaction on auxin. Depending on the plant species tested, Agrobacterium strains carrying mutations in gene e induced only small or almost no detectable crown gall tumours. According to these mutational studies and the protein homologies observed, the gene e product is suggested to be involved in tumour formation. Infection of several plant species with Agrobacterium carrying a mutated gene f, as well as expression of the gene f in transgenic tobacco plants did not lead to visible morphological changes. Therefore, in contrast to gene e, the gene f seems not to be essential for tumour formation. In order to study whether gene f is an active gene, its expression in agrobacteria and plants was monitored by translational lacZ fusion. In planta, the putative gene f-promoter mediates a tissue-specific expression pattern. Although gene f was expressed in free-living agrobacteria as well as in transgenic plants, the function of the f locus remained unclear. DNA homology studies with the f gene region revealed a mosaic-like DNA structure, indicating that this locus might be the result of genetic exchanges between different Agrobacterium strains during evolution.
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Affiliation(s)
- I Broer
- Lehrstuhl für Genetik, Fakultät für Biologie, Universität Bielefeld, Germany
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Drevet C, Brasileiro AC, Jouanin L. Oncogene arrangement in a shooty strain of Agrobacterium tumefaciens. PLANT MOLECULAR BIOLOGY 1994; 25:83-90. [PMID: 8003699 DOI: 10.1007/bf00024200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The Agrobacterium tumefaciens nopaline strain 82.139 induces non-teratogenic shooty tumours on several plant species. We have determined the position of the T-region oncogenes in a 11.4 kb Xba I fragment which shows a general organization similar to its pTiC58 counterpart. Sequence analysis of the 4.7 kb right part of this fragment allowed us to identify the pTi82.139 ipt, 6b and nos coding sequences. pTi82.139 lacks the 6a gene, which lies between the ipt and 6b genes in pTiC58. The intervening region between the 6b and the nos genes contains an additional ORF with homology to ORF 21 (transcript 3') from the TR-DNA of octopine strain pTi15955.
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Affiliation(s)
- C Drevet
- Laboratoire de Biologie Cellulaire, INRA, Versailles, France
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Tepfer M, Vilaine F, Carneiro M, Pautot V, Charbonnier C, Rossignol M, Vansuyt G, Prinsen E, Van Onckelen H, Legué V, Perbal G, Besnard C, Noin M, Guivarc'h A, Chriqui D. Physiological and morphological consequences of expression of therolAgene in transgenic tobacco plants. ACTA ACUST UNITED AC 1993. [DOI: 10.1080/12538078.1993.10515646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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49
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Sun LY, Touraud G, Charbonnier C, Tepfer D. Modification of phenotype in Belgian endive (Cichorium intybus) through genetic transformation byAgrobacterium rhizogenes: conversion from biennial to annual flowering. Transgenic Res 1991. [DOI: 10.1007/bf02512992] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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50
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Use of Agrobacterium rhizogenes to Create Chimeric Apple Trees Through Genetic Grafting. Nat Biotechnol 1991. [DOI: 10.1038/nbt0191-80] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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