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Lukhovitskaya N, Brown K, Hua L, Pate AE, Carr JP, Firth AE. A novel ilarvirus protein CP-RT is expressed via stop codon readthrough and suppresses RDR6-dependent RNA silencing. PLoS Pathog 2024; 20:e1012034. [PMID: 38814986 PMCID: PMC11166343 DOI: 10.1371/journal.ppat.1012034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 06/11/2024] [Accepted: 05/03/2024] [Indexed: 06/01/2024] Open
Abstract
Ilarviruses are a relatively understudied but important group of plant RNA viruses that includes a number of crop pathogens. Their genomes comprise three RNA segments encoding two replicase subunits, movement protein, coat protein (CP), and (in some ilarvirus subgroups) a protein that suppresses RNA silencing. Here we report that, in many ilarviruses, RNA3 encodes an additional protein (termed CP-RT) as a result of ribosomal readthrough of the CP stop codon into a short downstream readthrough (RT) ORF. Using asparagus virus 2 as a model, we find that CP-RT is expressed in planta where it functions as a weak suppressor of RNA silencing. CP-RT expression is essential for persistent systemic infection in leaves and shoot apical meristem. CP-RT function is dependent on a putative zinc-finger motif within RT. Replacing the asparagus virus 2 RT with the RT of an ilarvirus from a different subgroup restored the ability to establish persistent infection. These findings open up a new avenue for research on ilarvirus silencing suppression, persistent meristem invasion and vertical transmission.
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Affiliation(s)
- Nina Lukhovitskaya
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Katherine Brown
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Lei Hua
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Adrienne E. Pate
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - John P. Carr
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Andrew E. Firth
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
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Hoffmann G, Incarbone M. A resilient bunch: stem cell antiviral immunity in plants. THE NEW PHYTOLOGIST 2024; 241:1415-1420. [PMID: 38058221 DOI: 10.1111/nph.19456] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 11/15/2023] [Indexed: 12/08/2023]
Abstract
Stem cells are vital for plant development and reproduction. The stem cells within shoot apical meristems are known to possess exceptionally effective antiviral defenses against pathogenic viruses which preclude their infection, yet how this is achieved remains poorly understood and scarcely investigated. In this Tansley Insight, we connect very recent experimental results with previous work to summarize the known molecular mechanisms determining stem cell antiviral immunity. More broadly, we attempt to define the viral features triggering immunity and the global consequences of virus infection in these essential cells. This brief article will highlight how these phenomena are fascinating, complex and often crucial for virus-host interactions, while emphasizing the potential for discovery in their investigation.
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Affiliation(s)
- Gesa Hoffmann
- Max Planck Institute of Molecular Plant Physiology (MPIMP), 1 Am Mühlenberg Strasse, 14476, Potsdam, Germany
| | - Marco Incarbone
- Max Planck Institute of Molecular Plant Physiology (MPIMP), 1 Am Mühlenberg Strasse, 14476, Potsdam, Germany
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Niu E, Liu H, Zhou H, Luo L, Wu Y, Andika IB, Sun L. Autophagy Inhibits Intercellular Transport of Citrus Leaf Blotch Virus by Targeting Viral Movement Protein. Viruses 2021; 13:2189. [PMID: 34834995 PMCID: PMC8619118 DOI: 10.3390/v13112189] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 12/12/2022] Open
Abstract
Autophagy is an evolutionarily conserved cellular-degradation mechanism implicated in antiviral defense in plants. Studies have shown that autophagy suppresses virus accumulation in cells; however, it has not been reported to specifically inhibit viral spread in plants. This study demonstrated that infection with citrus leaf blotch virus (CLBV; genus Citrivirus, family Betaflexiviridae) activated autophagy in Nicotiana benthamiana plants as indicated by the increase of autophagosome formation. Impairment of autophagy through silencing of N. benthamiana autophagy-related gene 5 (NbATG5) and NbATG7 enhanced cell-to-cell and systemic movement of CLBV; however, it did not affect CLBV accumulation when the systemic infection had been fully established. Treatment using an autophagy inhibitor or silencing of NbATG5 and NbATG7 revealed that transiently expressed movement protein (MP), but not coat protein, of CLBV was targeted by selective autophagy for degradation. Moreover, we identified that CLBV MP directly interacted with NbATG8C1 and NbATG8i, the isoforms of autophagy-related protein 8 (ATG8), which are key factors that usually bind cargo receptors for selective autophagy. Our results present a novel example in which autophagy specifically targets a viral MP to limit the intercellular spread of the virus in plants.
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Affiliation(s)
- Erbo Niu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (E.N.); (H.Z.); (L.L.)
| | - Huan Liu
- School of Modern Agriculture and Biotechnology, Ankang University, Ankang 725000, China;
| | - Hongsheng Zhou
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (E.N.); (H.Z.); (L.L.)
| | - Lian Luo
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (E.N.); (H.Z.); (L.L.)
| | - Yunfeng Wu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (E.N.); (H.Z.); (L.L.)
| | - Ida Bagus Andika
- College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao 266109, China
| | - Liying Sun
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Xianyang 712100, China; (E.N.); (H.Z.); (L.L.)
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Bradamante G, Mittelsten Scheid O, Incarbone M. Under siege: virus control in plant meristems and progeny. THE PLANT CELL 2021; 33:2523-2537. [PMID: 34015140 PMCID: PMC8408453 DOI: 10.1093/plcell/koab140] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 05/14/2021] [Indexed: 05/29/2023]
Abstract
In the arms race between plants and viruses, two frontiers have been utilized for decades to combat viral infections in agriculture. First, many pathogenic viruses are excluded from plant meristems, which allows the regeneration of virus-free plant material by tissue culture. Second, vertical transmission of viruses to the host progeny is often inefficient, thereby reducing the danger of viral transmission through seeds. Numerous reports point to the existence of tightly linked meristematic and transgenerational antiviral barriers that remain poorly understood. In this review, we summarize the current understanding of the molecular mechanisms that exclude viruses from plant stem cells and progeny. We also discuss the evidence connecting viral invasion of meristematic cells and the ability of plants to recover from acute infections. Research spanning decades performed on a variety of virus/host combinations has made clear that, beside morphological barriers, RNA interference (RNAi) plays a crucial role in preventing-or allowing-meristem invasion and vertical transmission. How a virus interacts with plant RNAi pathways in the meristem has profound effects on its symptomatology, persistence, replication rates, and, ultimately, entry into the host progeny.
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Affiliation(s)
- Gabriele Bradamante
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
| | - Ortrun Mittelsten Scheid
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
| | - Marco Incarbone
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), Vienna, Austria
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Ventimilla D, Velázquez K, Ruiz-Ruiz S, Terol J, Pérez-Amador MA, Vives MC, Guerri J, Talon M, Tadeo FR. IDA (INFLORESCENCE DEFICIENT IN ABSCISSION)-like peptides and HAE (HAESA)-like receptors regulate corolla abscission in Nicotiana benthamiana flowers. BMC PLANT BIOLOGY 2021; 21:226. [PMID: 34020584 PMCID: PMC8139003 DOI: 10.1186/s12870-021-02994-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 04/22/2021] [Indexed: 05/10/2023]
Abstract
BACKGROUND Abscission is an active, organized, and highly coordinated cell separation process enabling the detachment of aerial organs through the modification of cell-to-cell adhesion and breakdown of cell walls at specific sites on the plant body known as abscission zones. In Arabidopsis thaliana, abscission of floral organs and cauline leaves is regulated by the interaction of the hormonal peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), a pair of redundant receptor-like protein kinases, HAESA (HAE) and HAESA-LIKE2 (HSL2), and SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) co-receptors. However, the functionality of this abscission signaling module has not yet been demonstrated in other plant species. RESULTS The expression of the pair of NbenIDA1 homeologs and the receptor NbenHAE.1 was supressed at the base of the corolla tube by the inoculation of two virus-induced gene silencing (VIGS) constructs in Nicotiana benthamiana. These gene suppression events arrested corolla abscission but did not produce any obvious effect on plant growth. VIGS plants retained a higher number of corollas attached to the flowers than control plants, an observation related to a greater corolla breakstrength. The arrest of corolla abscission was associated with the preservation of the parenchyma tissue at the base of the corolla tube that, in contrast, was virtually collapsed in normal corollas. In contrast, the inoculation of a viral vector construct that increased the expression of NbenIDA1A at the base of the corolla tube negatively affected the growth of the inoculated plants accelerating the timing of both corolla senescence and abscission. However, the heterologous ectopic overexpression of citrus CitIDA3 and Arabidopsis AtIDA in N. benthamiana did not alter the standard plant phenotype suggesting that the proteolytic processing machinery was unable to yield active peptides. CONCLUSION Here, we demonstrate that the pair of NbenIDA1 homeologs encoding small peptides of the IDA-like family and the receptor NbenHAE.1 control cellular breakdown at the base of the corolla tube awhere an adventitious AZ should be formed and, therefore, corolla abscission in N. benthamiana flowers. Altogether, our results provide the first evidence supporting the notion that the IDA-HAE/HSL2 signaling module is conserved in angiosperms.
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Affiliation(s)
- Daniel Ventimilla
- Centro de Genómica - Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - Karelia Velázquez
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - Susana Ruiz-Ruiz
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - Javier Terol
- Centro de Genómica - Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - Miguel A. Pérez-Amador
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), CSIC-Universidad Politécnica de Valencia. CPI Ed. 8E, Camino de Vera s/n, 46022 Valencia, Spain
| | - Mª. Carmen Vives
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - José Guerri
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - Manuel Talon
- Centro de Genómica - Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
| | - Francisco R. Tadeo
- Centro de Genómica - Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, 46113 Valencia, Spain
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Salonia F, Ciacciulli A, Poles L, Pappalardo HD, La Malfa S, Licciardello C. New Plant Breeding Techniques in Citrus for the Improvement of Important Agronomic Traits. A Review. FRONTIERS IN PLANT SCIENCE 2020; 11:1234. [PMID: 32922420 PMCID: PMC7456868 DOI: 10.3389/fpls.2020.01234] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 07/28/2020] [Indexed: 05/18/2023]
Abstract
New plant breeding techniques (NPBTs) aim to overcome traditional breeding limits for fruit tree species, in order to obtain new varieties with improved organoleptic traits and resistance to biotic and abiotic stress, and to maintain fruit quality achieved over centuries by (clonal) selection. Knowledge on the gene(s) controlling a specific trait is essential for the use of NPBTs, such as genome editing and cisgenesis. In the framework of the international scientific community working on fruit tree species, including citrus, NPBTs have mainly been applied to address pathogen threats. Citrus could take advantage of NPBTs because of its complex species biology (seedlessness, apomixis, high heterozygosity, and long juvenility phase) and aptitude for in vitro manipulation. To our knowledge, genome editing in citrus via transgenesis has successful for induced resistance to Citrus bacterial canker in sweet orange and grapefruit using the resistance gene CsLOB1. In the future, NPBTs will also be used to improve fruit traits, making them healthier. The regeneration of plants following the application of NPBTs is a bottleneck, making it necessary to optimize the efficiency of current protocols. The strengths and weaknesses of using explants from young in vitro plantlets, and from mature plants, will be discussed. Other major issues addressed in this review are related to the requirement for marker-free systems and shortening the long juvenility phase. This review aims to summarize methods and approaches available in the literature that are suitable to citrus, focusing on the principles observed before the use of NPBTs.
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Affiliation(s)
- Fabrizio Salonia
- CREA - Research Centre for Olive, Fruit and Citrus Crops, Acireale, Italy
- Department of Agriculture, Food and Environment (Di3A), University of Catania, Catania, Italy
| | - Angelo Ciacciulli
- CREA - Research Centre for Olive, Fruit and Citrus Crops, Acireale, Italy
| | - Lara Poles
- CREA - Research Centre for Olive, Fruit and Citrus Crops, Acireale, Italy
- Department of Agriculture, Food and Environment (Di3A), University of Catania, Catania, Italy
| | | | - Stefano La Malfa
- Department of Agriculture, Food and Environment (Di3A), University of Catania, Catania, Italy
- *Correspondence: Stefano La Malfa, ; Concetta Licciardello,
| | - Concetta Licciardello
- CREA - Research Centre for Olive, Fruit and Citrus Crops, Acireale, Italy
- *Correspondence: Stefano La Malfa, ; Concetta Licciardello,
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Gómez‐Muñoz N, Velázquez K, Vives MC, Ruiz‐Ruiz S, Pina JA, Flores R, Moreno P, Guerri J. The resistance of sour orange to Citrus tristeza virus is mediated by both the salicylic acid and RNA silencing defence pathways. MOLECULAR PLANT PATHOLOGY 2017; 18:1253-1266. [PMID: 27588892 PMCID: PMC6638288 DOI: 10.1111/mpp.12488] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 08/26/2016] [Accepted: 08/30/2016] [Indexed: 05/08/2023]
Abstract
Citrus tristeza virus (CTV) induces in the field the decline and death of citrus varieties grafted on sour orange (SO) rootstock, which has forced the use of alternative decline-tolerant rootstocks in affected countries, despite the highly desirable agronomic features of the SO rootstock. Declining citrus plants display phloem necrosis below the bud union. In addition, SO is minimally susceptible to CTV compared with other citrus varieties, suggesting partial resistance of SO to CTV. Here, by silencing different citrus genes with a Citrus leaf blotch virus-based vector, we have examined the implication of the RNA silencing and salicylic acid (SA) defence pathways in the resistance of SO to CTV. Silencing of the genes RDR1, NPR1 and DCL2/DCL4, associated with these defence pathways, enhanced virus spread and accumulation in SO plants in comparison with non-silenced controls, whereas silencing of the genes NPR3/NPR4, associated with the hypersensitive response, produced a slight decrease in CTV accumulation and reduced stunting of SO grafted on CTV-infected rough lemon plants. We also found that the CTV RNA silencing suppressors p20 and p23 also suppress the SA signalling defence, with the suppressor activity being higher in the most virulent isolates.
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Affiliation(s)
- Neus Gómez‐Muñoz
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
| | - Karelia Velázquez
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
| | - María Carmen Vives
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
| | - Susana Ruiz‐Ruiz
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
| | - José Antonio Pina
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
| | - Ricardo Flores
- Instituto de Biología Molecular y Celular de Plantas (UPV‐CSIC), Universidad Politécnica de Valencia, Avenida de los NaranjosValencia46022Spain
| | - Pedro Moreno
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
| | - José Guerri
- Instituto Valenciano de Investigaciones Agrarias (IVIA)Centro de Protección Vegetal y BiotecnologíaMoncada, Valencia46113Spain
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Boissinot S, Pichon E, Sorin C, Piccini C, Scheidecker D, Ziegler-Graff V, Brault V. Systemic Propagation of a Fluorescent Infectious Clone of a Polerovirus Following Inoculation by Agrobacteria and Aphids. Viruses 2017; 9:E166. [PMID: 28661469 PMCID: PMC5537658 DOI: 10.3390/v9070166] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 06/16/2017] [Accepted: 06/22/2017] [Indexed: 11/16/2022] Open
Abstract
A fluorescent viral clone of the polerovirus Turnip yellows virus (TuYV) was engineered by introducing the Enhanced Green Fluorescent Protein (EGFP) sequence into the non-structural domain sequence of the readthrough protein, a minor capsid protein. The resulting recombinant virus, referred to as TuYV-RTGFP, was infectious in several plant species when delivered by agroinoculation and invaded efficiently non-inoculated leaves. As expected for poleroviruses, which infect only phloem cells, the fluorescence emitted by TuYV-RTGFP was restricted to the vasculature of infected plants. In addition, TuYV-RTGFP was aphid transmissible and enabled the observation of the initial sites of infection in the phloem after aphid probing in epidermal cells. The aphid-transmitted virus moved efficiently to leaves distant from the inoculation sites and importantly retained the EGFP sequence in the viral genome. This work reports on the first engineered member in the Luteoviridae family that can be visualized by fluorescence emission in systemic leaves of different plant species after agroinoculation or aphid transmission.
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Affiliation(s)
- Sylvaine Boissinot
- Université de Strasbourg, Institut National de la Recherche Agronomique, SVQV UMR-A 1131, 68000 Colmar, France.
| | - Elodie Pichon
- Université de Strasbourg, Institut National de la Recherche Agronomique, SVQV UMR-A 1131, 68000 Colmar, France.
- UMR 385 BGPI, Institut National de la Recherche Agronomique-Centre de Coopération Internationale en Recherche Agronomique pour le Développement, SupAgro, CIRAD TA-A54/K, Campus International de Baillarguet, 34398 Montpellier, France.
| | - Céline Sorin
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, UPR 2357, Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France.
- Institute of Plant Science Paris Saclay (IPS2), CNRS, INRA, University Paris Diderot, University of Paris-Saclay, 91405 Orsay, France.
| | - Céline Piccini
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, UPR 2357, Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France.
| | - Danièle Scheidecker
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, UPR 2357, Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France.
| | - Véronique Ziegler-Graff
- Institut de Biologie Moléculaire des Plantes, Centre National de la Recherche Scientifique, UPR 2357, Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg, France.
| | - Véronique Brault
- Université de Strasbourg, Institut National de la Recherche Agronomique, SVQV UMR-A 1131, 68000 Colmar, France.
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Velázquez K, Agüero J, Vives MC, Aleza P, Pina JA, Moreno P, Navarro L, Guerri J. Precocious flowering of juvenile citrus induced by a viral vector based on Citrus leaf blotch virus: a new tool for genetics and breeding. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:1976-85. [PMID: 26920394 PMCID: PMC5043495 DOI: 10.1111/pbi.12555] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/04/2016] [Accepted: 02/19/2016] [Indexed: 05/17/2023]
Abstract
The long juvenile period of citrus trees (often more than 6 years) has hindered genetic improvement by traditional breeding methods and genetic studies. In this work, we have developed a biotechnology tool to promote transition from the vegetative to the reproductive phase in juvenile citrus plants by expression of the Arabidopsis thaliana or citrus FLOWERING LOCUS T (FT) genes using a Citrus leaf blotch virus-based vector (clbvINpr-AtFT and clbvINpr-CiFT, respectively). Citrus plants of different genotypes graft inoculated with either of these vectors started flowering within 4-6 months, with no alteration of the plant architecture, leaf, flower or fruit morphology in comparison with noninoculated adult plants. The vector did not integrate in or recombine with the plant genome nor was it pollen or vector transmissible, albeit seed transmission at low rate was detected. The clbvINpr-AtFT is very stable, and flowering was observed over a period of at least 5 years. Precocious flowering of juvenile citrus plants after vector infection provides a helpful and safe tool to dramatically speed up genetic studies and breeding programmes.
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Affiliation(s)
- Karelia Velázquez
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Jesús Agüero
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - María C Vives
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Pablo Aleza
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - José A Pina
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Pedro Moreno
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - Luis Navarro
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain
| | - José Guerri
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Moncada, Valencia, Spain.
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10
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Agüero J, Vives MDC, Velázquez K, Pina JA, Navarro L, Moreno P, Guerri J. Effectiveness of gene silencing induced by viral vectors based on Citrus leaf blotch virus is different in Nicotiana benthamiana and citrus plants. Virology 2014; 460-461:154-64. [PMID: 25010281 DOI: 10.1016/j.virol.2014.04.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 02/12/2014] [Accepted: 04/12/2014] [Indexed: 11/23/2022]
Abstract
Virus induced gene silencing (VIGS) is an effective technology for gene function analysis in plants. We assessed the VIGS effectiveness in Nicotiana benthamiana and citrus plants of different Citrus leaf blotch virus (CLBV)-based vectors, using insets of the phytoene desaturase (pds) gene. While in N. benthamiana the silencing phenotype was induced only by the construct carrying a 58-nt pds hairpin, in citrus plants all the constructs induced the silencing phenotype. Differences in the generation of secondary small interfering RNAs in both species are believed to be responsible for differential host-species effects. The ability of CLBV-based vectors to silence different endogenous citrus genes was further confirmed. Since CLBV-based vectors are known to be stable and induce VIGS in successive flushes for several months, these vectors provide an important genomic tool and it is expected that they will be useful to analyze gene function by reverse genetics in the long-lived citrus plants.
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Affiliation(s)
- Jesus Agüero
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain
| | - María del Carmen Vives
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain
| | - Karelia Velázquez
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain
| | - José Antonio Pina
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain
| | - Luis Navarro
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain
| | - Pedro Moreno
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain
| | - Jose Guerri
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera Km. 4.5, Moncada, 46113 Valencia, Spain.
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Cuenca J, Aleza P, Vicent A, Brunel D, Ollitrault P, Navarro L. Genetically based location from triploid populations and gene ontology of a 3.3-mb genome region linked to Alternaria brown spot resistance in citrus reveal clusters of resistance genes. PLoS One 2013; 8:e76755. [PMID: 24116149 PMCID: PMC3792864 DOI: 10.1371/journal.pone.0076755] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 08/23/2013] [Indexed: 12/17/2022] Open
Abstract
Genetic analysis of phenotypical traits and marker-trait association in polyploid species is generally considered as a challenge. In the present work, different approaches were combined taking advantage of the particular genetic structures of 2n gametes resulting from second division restitution (SDR) to map a genome region linked to Alternaria brown spot (ABS) resistance in triploid citrus progeny. ABS in citrus is a serious disease caused by the tangerine pathotype of the fungus Alternaria alternata. This pathogen produces ACT-toxin, which induces necrotic lesions on fruit and young leaves, defoliation and fruit drop in susceptible genotypes. It is a strong concern for triploid breeding programs aiming to produce seedless mandarin cultivars. The monolocus dominant inheritance of susceptibility, proposed on the basis of diploid population studies, was corroborated in triploid progeny. Bulk segregant analysis coupled with genome scan using a large set of genetically mapped SNP markers and targeted genetic mapping by half tetrad analysis, using SSR and SNP markers, allowed locating a 3.3 Mb genomic region linked to ABS resistance near the centromere of chromosome III. Clusters of resistance genes were identified by gene ontology analysis of this genomic region. Some of these genes are good candidates to control the dominant susceptibility to the ACT-toxin. SSR and SNP markers were developed for efficient early marker-assisted selection of ABS resistant hybrids.
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Affiliation(s)
- José Cuenca
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias. Moncada, Valencia, Spain
| | - Pablo Aleza
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias. Moncada, Valencia, Spain
| | - Antonio Vicent
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias. Moncada, Valencia, Spain
| | - Dominique Brunel
- Etude du Polymorphisme des Genomes Vegetaux, Institut National de la Recherche Agronomique, Évry, France
| | - Patrick Ollitrault
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias. Moncada, Valencia, Spain
- Etude du Polymorphisme des Genomes Vegetaux, Institut National de la Recherche Agronomique, Évry, France
- BIOS Department, Amélioration Génétique des Espèces à Multiplication Végétative. Centre de Coopeération Internationale en Recherche Agronomique pour le Développement, Montpellier, France
| | - Luis Navarro
- Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias. Moncada, Valencia, Spain
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