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Mei G, Chen A, Wang Y, Li S, Wu M, Hu Y, Liu X, Hou X. A simple and efficient in planta transformation method based on the active regeneration capacity of plants. Plant Commun 2024; 5:100822. [PMID: 38243598 PMCID: PMC11009361 DOI: 10.1016/j.xplc.2024.100822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 09/18/2023] [Accepted: 01/12/2024] [Indexed: 01/21/2024]
Abstract
Plant genetic transformation strategies serve as essential tools for the genetic engineering and advanced molecular breeding of plants. However, the complicated operational protocols and low efficiency of current transformation strategies restrict the genetic modification of most plant species. This paper describes the development of the regenerative activity-dependent in planta injection delivery (RAPID) method based on the active regeneration capacity of plants. In this method, Agrobacterium tumefaciens is delivered to plant meristems via injection to induce transfected nascent tissues. Stable transgenic plants can be obtained by subsequent vegetative propagation of the positive nascent tissues. The method was successfully used for transformation of plants with strong regeneration capacity, including different genotypes of sweet potato (Ipomoea batatas), potato (Solanum tuberosum), and bayhops (Ipomoea pes-caprae). Compared with traditional transformation methods, RAPID has a much higher transformation efficiency and shorter duration, and it does not require tissue culture procedures. The RAPID method therefore overcomes the limitations of traditional methods to enable rapid in planta transformation and can be potentially applied to a wide range of plant species that are capable of active regeneration.
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Affiliation(s)
- Guoguo Mei
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ao Chen
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yaru Wang
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuquan Li
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Minyi Wu
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yilong Hu
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xu Liu
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xingliang Hou
- Guangdong Provincial Key Laboratory of Applied Botany & State Key Laboratory of Plant Diversity and Specialty Crops, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Anwar W, Amin H, Khan HAA, Akhter A, Bashir U, Anjum T, Kalsoom R, Javed MA, Zohaib KA. Chitinase of Trichoderma longibrachiatum for control of Aphis gossypii in cotton plants. Sci Rep 2023; 13:13181. [PMID: 37580401 PMCID: PMC10425378 DOI: 10.1038/s41598-023-39965-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 08/02/2023] [Indexed: 08/16/2023] Open
Abstract
Chitinase-producing fungi have now engrossed attention as one of the potential agents for the control of insect pests. Entomopathogenic fungi are used in different regions of the world to control economically important insects. However, the role of fungal chitinases are not well studied in their infection mechanism to insects. In this study, Chitinase of entomopathogenic fungi Trichoderma longibrachiatum was evaluated to control Aphis gossypii. For this purpose, fungal chitinase (Chit1) gene from the genomic DNA of T. longibrachiatum were isolated, amplified and characterised. Genomic analysis of the amplified Chit1 showed that this gene has homology to family 18 of glycosyl hydrolyses. Further, Chit1 was expressed in the cotton plant for transient expression through the Geminivirus-mediated gene silencing vector derived from Cotton Leaf Crumple Virus (CLCrV). Transformed cotton plants showed greater chitinase activity than control, and they were resistant against nymphs and adults of A. gossypii. About 38.75% and 21.67% mortality of both nymphs and adults, respectively, were observed by using Chit1 of T. longibrachiatum. It is concluded that T. longibrachiatum showed promising results in controlling aphids by producing fungal chitinase in cotton plants and could be used as an effective method in the future.
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Affiliation(s)
- Waheed Anwar
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan.
| | - Huma Amin
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Hafiz Azhar Ali Khan
- Department of Entomology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
- Institute of Zoology, Faculty of Life Sciences, University of the Punjab, Lahore, Pakistan
| | - Adnan Akhter
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Uzma Bashir
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Tehmina Anjum
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Rabia Kalsoom
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Muhammad Asim Javed
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Karamat Ali Zohaib
- Department of Plant Pathology, Faculty of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
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3
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Jagram N, Dasgupta I. Principles and practice of virus induced gene silencing for functional genomics in plants. Virus Genes 2023; 59:173-187. [PMID: 36266497 DOI: 10.1007/s11262-022-01941-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 10/05/2022] [Indexed: 10/24/2022]
Abstract
Virus induced gene silencing (VIGS) has, of late, emerged as an important tool for transient silencing of genes in plants. This is now being increasingly used to determine functions of novel genes in a wide variety of plants, many of which are important crops yielding food and fiber or are sources of products having pharmaceutical uses. The technology for VIGS comprises the development of vectors derived from viruses, choosing the optimal orientation and size of the gene to be targeted and adopting the most suitable method of inoculation. This review gives a brief overview of the main aspects of VIGS technology as is being practiced. It also discusses the challenges the technology faces and the possible way ahead to improve its robustness, so that the technology finds wider applications.
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Affiliation(s)
- Neelam Jagram
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India
| | - Indranil Dasgupta
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, 110021, India.
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Li G, Li Y, Yao X, Lu L. Establishment of a Virus-Induced Gene-Silencing (VIGS) System in Tea Plant and Its Use in the Functional Analysis of CsTCS1. Int J Mol Sci 2022; 24. [PMID: 36613837 DOI: 10.3390/ijms24010392] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 12/09/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
Tea (Camellia sinensis [L.] O. Kuntze) is an important global economic crop and is considered to enhance health. However, the functions of many genes in tea plants are unknown. Virus-induced gene silencing (VIGS) mediated by tobacco rattle virus (TRV) is an effective tool for the analysis of gene functions, although this method has rarely been reported in tea plants. In this study, we established an effective VIGS-mediated gene knockout technology to understand the functional identification of large-scale genomic sequences in tea plants. The results showed that the VIGS system was verified by detecting the virus and using a real-time quantitative reverse transcription PCR (qRT-PCR) analysis. The reporter gene CsPOR1 (protochlorophyllide oxidoreductase) was silenced using the vacuum infiltration method, and typical photobleaching and albino symptoms were observed in newly sprouted leaves at the whole plant level of tea after infection for 12 d and 25 d. After optimization, the VIGS system was successfully used to silence the tea plant CsTCS1 (caffeine synthase) gene. The results showed that the relative caffeine content was reduced 6.26-fold compared with the control, and the level of expression of CsPOR1 decreased by approximately 3.12-fold in plants in which CsPOR1 was silenced. These results demonstrate that VIGS can be quickly and efficiently used to analyze the function of genes in tea plants. The successful establishment of VIGS could eliminate the need for tissue culture by providing an effective method to study gene function in tea plants and accelerate the process of functional genome research in tea.
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Villanueva-alonzo HDJ, Haro-álvarez AP, Alvarado-segura AA, Valle-gough RE, Collí-mull JG, Cal-torres A, Arana-argáez VE, Torres-romero JC, Moreno-valenzuela OA, Nic-can G, Ayil-gutiérrez BA, Acosta-viana KY. A Method to Produce vsiRNAs in Plants with Cross-Kingdom Gene Silencing Capacity. Applied Sciences 2022; 12:5329. [DOI: 10.3390/app12115329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Plants have evolved defense mechanisms to suppress viral transcription and replication by transcriptional and post-transcriptional gene silencing mediated by virus-derived small interfering RNAs (vsiRNAs). Based on this response, virus-induced gene silencing (VIGS)-based technology has been developed to silence target genes on either host plants or insect pests. This mechanism could also be used for the silencing of genes of interest in the medical field. We used the VIGS vector pEuMV-YP:Krt18, which was obtained by inserting the Mus musculus (M. musculus) Krt18 sequence into pEuMV-YP:ΔAV1. The objective was to evaluate the capacity of pEuMV-YP:Krt18 to induce Nicotiana benthamiana (N. benthamiana) production of vsiRNAs of a specific sequence that belongs to neither the plant genome nor the wild virus genome, which were used to induce cross-kingdom gene silencing between plants and mammals. The percentage of vsiRNA for each viral gene was calculated from an sRNA library of N. benthamiana plants infected by pEuMV-YP: Krt18. When the vsiRNAs were characterized, it was found that they corresponded to all the genes of the pEuMV-YP:Krt18 vector. These vsiRNAs induced the silencing of the Krt18 gene in M. musculus macrophages, supporting the ability to use VIGS vectors in plants as biofactories for the production of sRNAs that induce gene silencing in mammals.
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Akbar S, Wei Y, Zhang MQ. RNA Interference: Promising Approach to Combat Plant Viruses. Int J Mol Sci 2022; 23:ijms23105312. [PMID: 35628126 PMCID: PMC9142109 DOI: 10.3390/ijms23105312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/06/2022] [Accepted: 05/07/2022] [Indexed: 11/16/2022] Open
Abstract
Plant viruses are devastating plant pathogens that severely affect crop yield and quality. Plants have developed multiple lines of defense systems to combat viral infection. Gene silencing/RNA interference is the key defense system in plants that inhibits the virulence and multiplication of pathogens. The general mechanism of RNAi involves (i) the transcription and cleavage of dsRNA into small RNA molecules, such as microRNA (miRNA), or small interfering RNA (siRNA), (ii) the loading of siRNA/miRNA into an RNA Induced Silencing Complex (RISC), (iii) complementary base pairing between siRNA/miRNA with a targeted gene, and (iv) the cleavage or repression of a target gene with an Argonaute (AGO) protein. This natural RNAi pathway could introduce transgenes targeting various viral genes to induce gene silencing. Different RNAi pathways are reported for the artificial silencing of viral genes. These include Host-Induced Gene Silencing (HIGS), Virus-Induced Gene Silencing (VIGS), and Spray-Induced Gene Silencing (SIGS). There are significant limitations in HIGS and VIGS technology, such as lengthy and time-consuming processes, off-target effects, and public concerns regarding genetically modified (GM) transgenic plants. Here, we provide in-depth knowledge regarding SIGS, which efficiently provides RNAi resistance development against targeted genes without the need for GM transgenic plants. We give an overview of the defense system of plants against viral infection, including a detailed mechanism of RNAi, small RNA molecules and their types, and various kinds of RNAi pathways. This review will describe how RNA interference provides the antiviral defense, recent improvements, and their limitations.
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Affiliation(s)
- Sehrish Akbar
- Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory for Conservation and Utilization of Agro Bioresources, Guangxi University, Nanning 530005, China; (S.A.); (Y.W.)
| | - Yao Wei
- Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory for Conservation and Utilization of Agro Bioresources, Guangxi University, Nanning 530005, China; (S.A.); (Y.W.)
| | - Mu-Qing Zhang
- Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory for Conservation and Utilization of Agro Bioresources, Guangxi University, Nanning 530005, China; (S.A.); (Y.W.)
- IRREC-IFAS, University of Florida, Fort Pierce, FL 34945, USA
- Correspondence: or
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Abstract
A persistent issue in the agricultural sector worldwide is the intensive damage caused to crops by the geminivirus family of viruses. The diverse types of viruses, rapid virus evolution rate, and broad host range make this group of viruses one of the most devastating in nature, leading to millions of dollars' worth of crop damage. Geminiviruses have a small genome and can be either monopartite or bipartite, with or without satellites. Their ability to independently replicate within the plant without integration into the host genome and the relatively easy handling make them excellent candidates for plant bioengineering. This aspect is of great importance as geminiviruses can act as natural nanoparticles in plants which can be utilized for a plethora of functions ranging from vaccine development systems to geminivirus-induced gene silencing (GIGS), through deconstructed viral vectors. Thus, the investigation of these plant viruses is pertinent to understanding their crucial roles in nature and subsequently utilizing them as beneficial tools in functional genomics. This review, therefore, highlights some of the characteristics of these viruses that can be deemed significant and the subsequent successful case studies for exploitation of these potentially significant pathogens for role mining in functional biology.
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Affiliation(s)
- Bipasha Bhattacharjee
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- Plant Virology Laboratory, Division of Biotechnology, CSIR-Institute of Himalayan Bioresource Technology, Palampur, India
| | - Vipin Hallan
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
- Plant Virology Laboratory, Division of Biotechnology, CSIR-Institute of Himalayan Bioresource Technology, Palampur, India
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8
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He Y, Mudgett M, Zhao Y. Advances in gene editing without residual transgenes in plants. Plant Physiol 2022; 188:1757-1768. [PMID: 34893903 PMCID: PMC8968301 DOI: 10.1093/plphys/kiab574] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/09/2021] [Indexed: 05/24/2023]
Abstract
Transgene residuals in edited plants affect genetic analysis, pose off-target risks, and cause regulatory concerns. Several strategies have been developed to efficiently edit target genes without leaving any transgenes in plants. Some approaches directly address this issue by editing plant genomes with DNA-free reagents. On the other hand, DNA-based techniques require another step for ensuring plants are transgene-free. Fluorescent markers, pigments, and chemical treatments have all been employed as tools to distinguish transgenic plants from transgene-free plants quickly and easily. Moreover, suicide genes have been used to trigger self-elimination of transgenic plants, greatly improving the efficiency of isolating the desired transgene-free plants. Transgenes can also be excised from plant genomes using site-specific recombination, transposition or gene editing nucleases, providing a strategy for editing asexually produced plants. Finally, haploid induction coupled with gene editing may make it feasible to edit plants that are recalcitrant to transformation. Here, we evaluate the strengths and weaknesses of recently developed approaches for obtaining edited plants without transgene residuals.
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Affiliation(s)
- Yubing He
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- Collaborative Innovation Center for Modern Crop Production Co-sponsored by Province and Ministry, Nanjing Agricultural University, Nanjing 210095, China
- Excellence and Innovation Center, Jiangsu Academy of Agricultural Science, Nanjing 210014, China
| | - Michael Mudgett
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California 92093-0116, USA
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Zhao JH, Guo HS. RNA silencing: From discovery and elucidation to application and perspectives. J Integr Plant Biol 2022; 64:476-498. [PMID: 34964265 DOI: 10.1111/jipb.13213] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/26/2021] [Indexed: 06/14/2023]
Abstract
RNA silencing (or RNA interference, RNAi) is a conserved mechanism for regulating gene expression in eukaryotes. The discovery of natural trans-kingdom RNAi indicated that small RNAs act as signaling molecules and enable communication between organisms in different kingdoms. The phenomenon and potential mechanisms of trans-kingdom RNAi are among the most exciting research topics. To better understand trans-kingdom RNAi, we review the history of the discovery and elucidation of RNAi mechanisms. Based on canonical RNAi mechanisms, we summarize the major points of divergence around RNAi pathways in the main eukaryotes' kingdoms, including plants, animals, and fungi. We review the representative incidents associated with the mechanisms and applications of trans-kingdom RNAi in crop protection, and discuss the critical factors that should be considered to develop successful trans-kingdom RNAi-based crop protection strategies.
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Affiliation(s)
- Jian-Hua Zhao
- State Key Laboratory of Plant Genomics, Institute of Microbiology, the Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Hui-Shan Guo
- State Key Laboratory of Plant Genomics, Institute of Microbiology, the Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of the Chinese Academy of Sciences, Beijing, 100049, China
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Wang Y, Huang N, Ye N, Qiu L, Li Y, Ma H. An Efficient Virus-Induced Gene Silencing System for Functional Genomics Research in Walnut ( Juglans regia L.) Fruits. Front Plant Sci 2021; 12:661633. [PMID: 34249033 PMCID: PMC8261060 DOI: 10.3389/fpls.2021.661633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/21/2021] [Indexed: 06/13/2023]
Abstract
The Persian walnut (Juglans regia L.) is a leading source of woody oil in warm temperate regions and has high nutritional and medicinal values. It also provides both tree nuts and woody products. Nevertheless, incomplete characterization of the walnut genetic system limits the walnut gene function analysis. This study used the tobacco rattle virus (TRV) vector to construct an infectious pTRV-JrPDS recombinant clone. A co-culture inoculation method utilizing Agrobacterium was screened out from four inoculation methods and optimized to set up an efficient virus-induced gene silencing (VIGS) system for J. regia fruit. The optimized VIGS-TRV system induced complete photobleaching phenotype on the walnut fruits of four cultivars, and the JrPDS transcript levels decreased by up to 88% at 8 days post-inoculation (dpi). While those of browning-related J. regia polyphenol oxidase (PPO) genes JrPPO1 and JrPPO2 decreased by 67 and 80% at 8 dpi, respectively, accompanied by a significant reduction in fruit browning phenotype. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis screening and Western Blot showed that the PPO protein levels were significantly reduced. Moreover, a model of TRV-mediated VIGS system for inoculating J. regia fruit with efficient silence efficiency via co-culture was developed. These results indicate that the VIGS-TRV system is an efficient tool for rapid gene function analysis in J. regia fruits.
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Abstract
Protection against microbial infection in eukaryotes is provided by diverse cellular and molecular mechanisms. Here, we present a comparative view of the antiviral activity of virus-derived small interfering RNAs in fungi, plants, invertebrates and mammals, detailing the mechanisms for their production, amplification and activity. We also highlight the recent discovery of viral PIWI-interacting RNAs in animals and a new role for mobile host and pathogen small RNAs in plant defence against eukaryotic pathogens. In turn, viruses that infect plants, insects and mammals, as well as eukaryotic pathogens of plants, have evolved specific virulence proteins that suppress RNA interference (RNAi). Together, these advances suggest that an antimicrobial function of the RNAi pathway is conserved across eukaryotic kingdoms.
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Anwar W, Javed MA, Shahid AA, Nawaz K, Akhter A, Ur Rehman MZ, Hameed U, Iftikhar S, Haider MS. Chitinase genes from Metarhizium anisopliae for the control of whitefly in cotton. R Soc Open Sci 2019; 6:190412. [PMID: 31598241 PMCID: PMC6731705 DOI: 10.1098/rsos.190412] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 08/01/2019] [Indexed: 06/01/2023]
Abstract
Entomopathogenic fungi produces endochitianses, involved in the degradation of insect chitin to facilitate the infection process. Endochitinases (Chit1) gene of family 18 glycosyl hydrolyses were amplified, cloned and characterized from genomic DNA of two isolates of Metarhizium anisopliae. Catalytic motif of family 18 glycosyl hydrolyses was found in Chit1 of M. anisopliae, while no signal peptide was found in any isolate, whereas substrate-binding motif was found in Chit1 of both isolates. Phylogenetic analysis revealed the evolutionary relationship among the fungal chitinases of Metarhizium. The Chit1 amplified were closely related to the family 18 glycosyl hydrolyses. Transient expressions of Chit1 in cotton plants using Geminivirus-mediated gene silencing vector of Cotton Leaf Crumple Virus (CLCrV) revealed the chitinase activity of Chit1 genes amplified from both of the isolates of M. anisopliae when compared with the control. Transformed cotton plants were virulent against fourth instar nymphal and adult stages of Bemisia tabaci which resulted in the mortality of both fourth instar nymphal and adult B. tabaci. Thus, the fungal chitinases expressed in cotton plants played a vital role in plant defence against B. tabaci. However, further studies are required to explore the comparative effectiveness of chitinases from different fungal strains against economically important insect pests.
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Affiliation(s)
- Waheed Anwar
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Muhammad Asim Javed
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Ahmad Ali Shahid
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Kiran Nawaz
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Adnan Akhter
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | | | - Usman Hameed
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
| | - Sehrish Iftikhar
- Institute of Agricultural Sciences, University of the Punjab, Lahore, Pakistan
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Dommes AB, Gross T, Herbert DB, Kivivirta KI, Becker A. Virus-induced gene silencing: empowering genetics in non-model organisms. J Exp Bot 2019; 70:757-770. [PMID: 30452695 DOI: 10.1093/jxb/ery411] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 11/08/2018] [Indexed: 05/19/2023]
Abstract
Virus-induced gene silencing (VIGS) is an RNA interference-based technology used to transiently knock down target gene expression by utilizing modified plant viral genomes. VIGS can be adapted to many angiosperm species that cover large phylogenetic distances, allowing the analysis of gene functions in species that are not amenable to stable genetic transformation. With a vast amount of sequence information already available and even more likely to become available in the future, VIGS provides a means to analyze the functions of candidate genes identified in large genomic or transcriptomic screens. Here, we provide a comprehensive overview of target species and VIGS vector systems, assess recent key publications in the field, and explain how plant viruses are modified to serve as VIGS vectors. As many reports on the VIGS technique are being published, we also propose minimal reporting guidelines for carrying out these experiments, with the aim of increasing comparability between experiments. Finally, we propose methods for the statistical evaluation of phenotypic results obtained with VIGS-treated plants, as analysis is challenging due to the predominantly transient nature of the silencing effect.
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Affiliation(s)
- Anna B Dommes
- Institute of Botany, Justus-Liebig-University, Heinrich-Buff-Ring, Gießen, Germany
| | - Thomas Gross
- Institute of Botany, Justus-Liebig-University, Heinrich-Buff-Ring, Gießen, Germany
| | - Denise B Herbert
- Institute of Botany, Justus-Liebig-University, Heinrich-Buff-Ring, Gießen, Germany
| | - Kimmo I Kivivirta
- Institute of Botany, Justus-Liebig-University, Heinrich-Buff-Ring, Gießen, Germany
| | - Annette Becker
- Institute of Botany, Justus-Liebig-University, Heinrich-Buff-Ring, Gießen, Germany
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Bortolamiol-Bécet D, Monsion B, Chapuis S, Hleibieh K, Scheidecker D, Alioua A, Bogaert F, Revers F, Brault V, Ziegler-Graff V. Phloem-Triggered Virus-Induced Gene Silencing Using a Recombinant Polerovirus. Front Microbiol 2018; 9:2449. [PMID: 30405546 PMCID: PMC6206295 DOI: 10.3389/fmicb.2018.02449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/25/2018] [Indexed: 01/22/2023] Open
Abstract
The phloem-limited poleroviruses infect Arabidopsis thaliana without causing noticeable disease symptoms. In order to facilitate visual infection identification, we developed virus-induced gene silencing (VIGS) vectors derived from Turnip yellows virus (TuYV). Short sequences from the host gene AtCHLI1 required for chlorophyll biosynthesis [42 nucleotides in sense or antisense orientation or as an inverted-repeat (IR), or an 81 nucleotide sense fragment] were inserted into the 3' non-coding region of the TuYV genome to screen for the most efficient and robust silencing vector. All recombinant viruses produced a clear vein chlorosis phenotype on infected Arabidopsis plants due to the expression inhibition of the AtCHLI1 gene. The introduction of a sense-oriented sequence into TuYV genome resulted in a virus exhibiting a more sustainable chlorosis than the virus containing an IR of the same length. This observation was correlated with a higher stability of the sense sequence insertion in the viral genome. In order to evaluate the impact of the TuYV silencing suppressor P0 in the VIGS mechanism a P0 knock-out mutation was introduced into the recombinant TuYV viruses. They induced a similar but milder vein clearing phenotype due to lower viral accumulation. This indicates that P0 does not hinder the performances of the TuYV silencing effect and confirms that in the viral infection context, P0 has no major impact on the production, propagation and action of the short distance silencing signal in phloem cells. Finally, we showed that TuYV can be used to strongly silence the phloem specific AtRTM1 gene. The TuYV-derived VIGS vectors therefore represent powerful tools to easily detect and monitor TuYV in infected plants and conduct functional analysis of phloem-restricted genes. Moreover this example indicates the potential of poleroviruses for use in functional genomic studies of agronomic plants.
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Affiliation(s)
- Diane Bortolamiol-Bécet
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France.,Architecture et Réactivité de l'ARN, Institut de biologie moléculaire et cellulaire CNRS-UPR 9002, Université de Strasbourg, Strasbourg, France
| | - Baptiste Monsion
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France.,UMR1161 Virologie, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, Maisons-Alfort, France
| | - Sophie Chapuis
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France
| | - Kamal Hleibieh
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France
| | - Danièle Scheidecker
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France
| | - Abdelmalek Alioua
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France
| | - Florent Bogaert
- SVQV, INRA UMR 1131, Université de Strasbourg, Colmar, France
| | - Frédéric Revers
- BFP, INRA UMR 1332, Univ. Bordeaux, Villenave d'Ornon, France.,BIOGECO, INRA UMR 1202, Univ. Bordeaux, Pessac, France
| | | | - Véronique Ziegler-Graff
- Institut de biologie moléculaire des plantes, CNRS-UPR 2357, Université de Strasbourg, Strasbourg, France
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Gedling CR, Ali EM, Gunadi A, Finer JJ, Xie K, Liu Y, Yoshikawa N, Qu F, Dorrance AE. Improved apple latent spherical virus-induced gene silencing in multiple soybean genotypes through direct inoculation of agro-infiltrated Nicotiana benthamiana extract. Plant Methods 2018. [PMID: 29527233 PMCID: PMC5838930 DOI: 10.1186/s13007-018-0286-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
BACKGROUND Virus induced gene silencing (VIGS) is a powerful genomics tool for interrogating the function of plant genes. Unfortunately, VIGS vectors often produce disease symptoms that interfere with the silencing phenotypes of target genes, or are frequently ineffective in certain plant genotypes or tissue types. This is especially true in crop plants like soybean [Glycine max (L.) Merr]. To address these shortcomings, we modified the inoculation procedure of a VIGS vector based on Apple latent spherical virus (ALSV). The efficacy of this new procedure was assessed in 19 soybean genotypes using a soybean Phytoene desaturase (GmPDS1) gene as the VIGS target. Silencing of GmPDS1 was easily scored as photo-bleached leaves and/or stems. RESULTS In this report, the ALSV VIGS vector was modified by mobilizing ALSV cDNAs into a binary vector compatible with Agrobacterium tumefaciens-mediated delivery, so that VIGS-triggering ALSV variants could be propagated in agro-infiltrated Nicotiana benthamiana leaves. Homogenate of these N. benthamiana leaves was then applied directly onto the unifoliate of young soybean seedlings to initiate systemic gene silencing. This rapid inoculation method bypassed the need for a particle bombardment apparatus. Among the 19 soybean genotypes evaluated with this new method, photo-bleaching indicative of GmPDS1 silencing was observed in nine, with two exhibiting photo-bleaching in 100% of the inoculated individuals. ALSV RNA was detected in pods, embryos, stems, leaves, and roots in symptomatic plants of four genotypes. CONCLUSIONS This modified protocol allowed for inoculation of soybean plants via simple mechanical rubbing with the homogenate of N. benthamiana leaves agro-infiltrated with ALSV VIGS constructs. More importantly, inoculated plants showed no apparent virus disease symptoms which could otherwise interfere with VIGS phenotypes. This streamlined procedure expanded this functional genomics tool to nine soybean genotypes.
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Affiliation(s)
- C. R. Gedling
- Department of Plant Pathology, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691 USA
| | - E. M. Ali
- Department of Plant Pathology, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691 USA
- Present Address: Washington State University, 1100 N Western Ave., Wenatchee, WA 98801 USA
| | - A. Gunadi
- Department of Horticulture and Crop Science, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691 USA
| | - J. J. Finer
- Department of Horticulture and Crop Science, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691 USA
| | - K. Xie
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, China
| | - Y. Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084 China
| | - N. Yoshikawa
- Plant Pathology Lab, Facility of Agriculture, Iwate University, Morioka, Japan
| | - F. Qu
- Department of Plant Pathology, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691 USA
| | - A. E. Dorrance
- Department of Plant Pathology, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691 USA
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16
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Beyene G, Chauhan RD, Taylor NJ. A rapid virus-induced gene silencing (VIGS) method for assessing resistance and susceptibility to cassava mosaic disease. Virol J 2017; 14:47. [PMID: 28270156 PMCID: PMC5341465 DOI: 10.1186/s12985-017-0716-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 02/23/2017] [Indexed: 11/18/2022] Open
Abstract
Background Cassava mosaic disease (CMD) is a major constraint to cassava production in sub-Saharan Africa. Under field conditions, evaluation for resistance to CMD takes 12–18 months, often conducted across multiple years and locations under pressure from whitefly-mediated transmission. Under greenhouse or laboratory settings, evaluation for resistance or susceptibility to CMD involves transmission of the causal viruses from an infected source to healthy plants through grafting, or by using Agrobacterium-mediated or biolistic delivery of infectious clones. Following inoculation, visual assessment for CMD symptom development and recovery requires 12–22 weeks. Here we report a rapid screening system for determining resistance and susceptibility to CMD based on virus-induced gene silencing (VIGS) of an endogenous cassava gene. Results A VIGS vector was developed based on an infectious clone of the virulent strain of East African cassava mosaic virus (EACMV-K201). A sequence from the cassava (Manihot esculenta) ortholog of Arabidopsis SPINDLY (SPY) was cloned into the CP position of the DNA-A genomic component and used to inoculate cassava plants by Helios® Gene Gun microparticle bombardment. Silencing of Manihot esculenta SPY (MeSPY) using MeSPY1-VIGS resulted in shoot-tip necrosis followed by death of the whole plant in CMD susceptible cassava plants within 2–4 weeks. CMD resistant cultivars were not affected and remained healthy after challenge with MeSPY1-VIGS. Significantly higher virus titers were detected in CMD-susceptible cassava lines compared to resistant controls and were correlated with a concomitant reduction in MeSPY expression in susceptible plants. Conclusions A rapid VIGS-based screening system was developed for assessing resistance and susceptibility to CMD. The method is space and resource efficient, reducing the time required to perform CMD screening to as little as 2–4 weeks. It can be employed as a high throughput rapid screening system to assess new cassava cultivars and for screening transgenic, gene edited and breeding lines under controlled growth conditions. Electronic supplementary material The online version of this article (doi:10.1186/s12985-017-0716-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Getu Beyene
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO, 63132, USA.
| | - Raj Deepika Chauhan
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO, 63132, USA
| | - Nigel J Taylor
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO, 63132, USA
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17
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Kushwaha NK, Chakraborty S. Chilli leaf curl virus-based vector for phloem-specific silencing of endogenous genes and overexpression of foreign genes. Appl Microbiol Biotechnol 2017; 101:2121-2129. [PMID: 27878582 DOI: 10.1007/s00253-016-7964-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/05/2016] [Accepted: 10/24/2016] [Indexed: 10/20/2022]
Abstract
Geminiviruses are the largest and most devastating group of plant viruses which contain ssDNA as a genetic material. Geminivirus-derived virus-induced gene silencing (VIGS) vectors have emerged as an efficient and simple tool to study functional genomics in various plants. However, previously developed VIGS vectors have certain limitations, owing to their inability to be used in tissue-specific functional study. In the present study, we developed a Chilli leaf curl virus (ChiLCV)-based VIGS vector for its tissue-specific utilization by replacing the coat protein gene (open reading frame (ORF) AV1) with the gene of interest for phytoene desaturase (PDS) of Nicotiana benthamiana. Functional validation of ChiLCV-based VIGS in N. benthamiana resulted in systemic silencing of PDS exclusively in the phloem region of inoculated plants. Furthermore, expression of enhanced green fluorescence protein (EGFP) using the same ChiLCV vector was verified in the phloem region of the inoculated plants. Our results also suggested that, during the early phase of infection, ChiLCV was associated with the phloem region, but at later stage of pathogenesis, it can spread into the adjoining non-vascular tissues. Taken together, the newly developed ChiLCV-based vector provides an efficient and versatile tool, which can be exploited to unveil the unknown functions of several phloem-specific genes.
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Affiliation(s)
- Nirbhay Kumar Kushwaha
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India.
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18
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Vega-Arreguín JC, Shimada-Beltrán H, Sevillano-Serrano J, Moffett P. Non-host Plant Resistance against Phytophthora capsici Is Mediated in Part by Members of the I2 R Gene Family in Nicotiana spp. Front Plant Sci 2017; 8:205. [PMID: 28261255 PMCID: PMC5309224 DOI: 10.3389/fpls.2017.00205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 02/03/2017] [Indexed: 05/29/2023]
Abstract
The identification of host genes associated with resistance to Phytophthora capsici is crucial to developing strategies of control against this oomycete pathogen. Since there are few sources of resistance to P. capsici in crop plants, non-host plants represent a promising source of resistance genes as well as excellent models to study P. capsici - plant interactions. We have previously shown that non-host resistance to P. capsici in Nicotiana spp. is mediated by the recognition of a specific P. capsici effector protein, PcAvr3a1 in a manner that suggests the involvement of a cognate disease resistance (R) genes. Here, we have used virus-induced gene silencing (VIGS) and transgenic tobacco plants expressing dsRNA in Nicotiana spp. to identify candidate R genes that mediate non-host resistance to P. capsici. Silencing of members of the I2 multigene family in the partially resistant plant N. edwardsonii and in the resistant N. tabacum resulted in compromised resistance to P. capsici. VIGS of two other components required for R gene-mediated resistance, EDS1 and SGT1, also enhanced susceptibility to P. capsici in N. edwardsonii, as well as in the susceptible plants N. benthamiana and N. clevelandii. The silencing of I2 family members in N. tabacum also compromised the recognition of PcAvr3a1. These results indicate that in this case, non-host resistance is mediated by the same components normally associated with race-specific resistance.
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Affiliation(s)
- Julio C. Vega-Arreguín
- Boyce Thompson Institute for Plant Research, IthacaNY, USA
- Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores – León, Universidad Nacional Autónoma de MexicoLeón, Mexico
| | - Harumi Shimada-Beltrán
- Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores – León, Universidad Nacional Autónoma de MexicoLeón, Mexico
| | - Jacobo Sevillano-Serrano
- Laboratorio de Ciencias Agrogenómicas, Escuela Nacional de Estudios Superiores – León, Universidad Nacional Autónoma de MexicoLeón, Mexico
| | - Peter Moffett
- Boyce Thompson Institute for Plant Research, IthacaNY, USA
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, SherbrookeQC, Canada
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19
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Luna-Rivero MS, Hernández-Zepeda C, Villanueva-Alonzo H, Minero-García Y, Castell-González SE, Moreno-Valenzuela OA. Expression of genes involved in the salicylic acid pathway in type h1 thioredoxin transiently silenced pepper plants during a begomovirus compatible interaction. Mol Genet Genomics 2016; 291:819-30. [PMID: 26606929 DOI: 10.1007/s00438-015-1148-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 11/13/2015] [Indexed: 12/31/2022]
Abstract
The type-h thioredoxins (TRXs) play a fundamental role in oxidative stress tolerance and defense responses against pathogens. In pepper plants, type-h TRXs participate in the defense mechanism against Cucumber mosaic virus. The goal of this study was to analyze the role of the CaTRXh1-cicy gene in pepper plants during compatible interaction with a DNA virus, the Euphorbia mosaic virus-Yucatan Peninsula (EuMV-YP). The effects of a transient silencing of the CaTRXh1-cicy gene in pepper plants wëre evaluated by observing the accumulation of viral DNA and the visible symptoms of pepper plants under different treatments. The accumulation of salicylic acid (SA) and the relative expression of the defense genes NPR1 and PR10 were also evaluated. Results showed that viral DNA accumulation was higher in transiently CaTRXh1-cicy silenced plants that were also infected with EuMV-YP. Symptoms in these plants were more severe compared to the non-silenced plants infected with EuMV-YP. The SA levels in the EuMV-YP-infected plants were rapidly induced at 1 h post infection (hpi) in comparison to the non-silenced plants inoculated with EuMV-YP. Additionally, in pepper plants infected with EuMV-YP, the expression of NPR1 decreased by up to 41 and 58 % at 28 days post infection (dpi) compared to the non-silenced pepper plants infected with only EuMV-YP and healthy non-inoculated pepper plants, respectively. PR10 gene expression decreased by up to 70 % at 28 dpi. Overall, the results indicate that the CaTRXh1-cicy gene participates in defense mechanisms during the compatible interaction of pepper plants with the EuMV-YP DNA virus.
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Abstract
The rapid progress in genome sequencing and transcriptome analysis in model and crop plants has made possible the identification of a vast number of genes potentially associated with economically important complex traits. The ultimate goal is to assign functions to these genes by using forward and reverse genetic screens. Plant viruses have been developed for virus-induced gene silencing (VIGS) to generate rapid gene knockdown phenotypes in numerous plant species. To fulfill its potential for high-throughput phenomics, it is of prime importance to ensure that parameters conditioning the VIGS response, i.e., plant-virus interactions and associated loss-of-function screens, are "fit for purpose" and optimized to unequivocally conclude the role of a gene of interest in relation to a given trait. This chapter will review and discuss the different strategies used for the development of VIGS-based phenomics in model and crop species.
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21
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Yin K, Han T, Liu G, Chen T, Wang Y, Yu AYL, Liu Y. A geminivirus-based guide RNA delivery system for CRISPR/Cas9 mediated plant genome editing. Sci Rep 2015; 5:14926. [PMID: 26450012 PMCID: PMC4598821 DOI: 10.1038/srep14926] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 09/09/2015] [Indexed: 01/20/2023] Open
Abstract
CRISPR/Cas has emerged as potent genome editing technology and has successfully been applied in many organisms, including several plant species. However, delivery of genome editing reagents remains a challenge in plants. Here, we report a virus-based guide RNA (gRNA) delivery system for CRISPR/Cas9 mediated plant genome editing (VIGE) that can be used to precisely target genome locations and cause mutations. VIGE is performed by using a modified Cabbage Leaf Curl virus (CaLCuV) vector to express gRNAs in stable transgenic plants expressing Cas9. DNA sequencing confirmed VIGE of endogenous NbPDS3 and NbIspH genes in non-inoculated leaves because CaLCuV can infect plants systemically. Moreover, VIGE of NbPDS3 and NbIspH in newly developed leaves caused photo-bleached phenotype. These results demonstrate that geminivirus-based VIGE could be a powerful tool in plant genome editing.
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Affiliation(s)
- Kangquan Yin
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Ting Han
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Guang Liu
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Tianyuan Chen
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Ying Wang
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Alice Yunzi L. Yu
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yule Liu
- Center for Plant Biology, MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua University, Beijing 100084, China
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Du J, Huang Z, Wang B, Sun H, Chen C, Ling HQ, Wu H. SlbHLH068 interacts with FER to regulate the iron-deficiency response in tomato. Ann Bot 2015; 116:23-34. [PMID: 26070639 PMCID: PMC4479748 DOI: 10.1093/aob/mcv058] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/24/2015] [Accepted: 03/27/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Iron is an essential micronutrient for all organisms and its uptake, translocation, distribution and utilization are regulated in a complex manner in plants. FER, isolated from tomato (Solanum lycopersicum), was the first transcription factor involved in the iron homeostasis of higher plants to be identified. A FER defect in the T3238fer mutant drastically downregulates the expression of iron uptake genes, such as ferric-chelate reductase 1 (LeFRO1) and iron-regulated transporter 1 (LeIRT1); however, the molecular mechanism by which FER regulates genes downstream remains unknown. The aim of this work was therefore to identify the gene that interacts with FER to regulate the iron-deficiency response in tomato. METHODS The homologue of the Arabidopsis Ib subgroup of the basic helix-loop-helix (bHLH) proteins, SlbHLH068, was identified by using the program BLASTP against the AtbHLH39 amino acid sequence in the tomato genome. The interaction between SlbHLH068 and FER was detected using yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays. In addition, virus-induced gene silencing (VIGS) was used to generate tomato plants in which SlbHLH068 expression was downregulated. The expression of genes was analysed using northern blot hybridization and multiple RT-PCR analysis. Seedlings of wild-type and mutant plants were grown under conditions of different nutrient deficiency. KEY RESULTS SlbHLH068 is highly upregulated in roots, leaves and stems in response to iron deficiency. An interaction between SlbHLH068 and FER was demonstrated using yeast two-hybrid and BiFC assays. The heterodimer formed by FER with SlbHLH068 directly bound to the promoter of LeFRO1 and activated the expression of its reporter gene in the yeast assay. The downregulation of SlbHLH068 expression by VIGS resulted in a reduction of LeFRO1 and LeIRT1 expression and iron accumulation in leaves and roots. CONCLUSIONS The results indicate that SlbHLH068, as a putative transcription factor, is involved in iron homeostasis in tomato via an interaction with FER.
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Affiliation(s)
- Juan Du
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
| | - Zongan Huang
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
| | - Biao Wang
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
| | - Hua Sun
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
| | - Chunlin Chen
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
| | - Hong-Qing Ling
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
| | - Huilan Wu
- The State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, West Beichen Road 1, Chaoyang District, Beijing 100101, China
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Jeyabharathy C, Shakila H, Usha R. Development of a VIGS vector based on the β-satellite DNA associated with bhendi yellow vein mosaic virus. Virus Res 2015; 195:73-8. [PMID: 25169741 DOI: 10.1016/j.virusres.2014.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/17/2014] [Accepted: 08/18/2014] [Indexed: 10/24/2022]
Abstract
Bhendi yellow vein mosaic virus (BYMV) is a monopartite begomovirus with an associated β-satellite. βC1 ORF encoded by the β-satellite is the symptom determinant and a strong suppressor of post transcriptional gene silencing. To create a virus induced gene silencing vector based upon the β-satellite associated with BYVMV the βC1 ORF was replaced with multiple cloning sites. GFP transgene and plant endogenous genes Su, PDS, PCNA and AGO1 were cloned into β-satellite based VIGS vector. GFP expression was silenced in the GFP expressing transgenic 16c Nicotiana benthamiana plants infiltrated with VIGS vector carrying GFP gene inside. N. benthamiana plants infiltrated with the VIGS vector harboring the endogenous genes Su, PDS, PCNA and AGO1 produced the phenotypic symptoms yellowing of the veins, photobleaching of the veins, stunting of the plant and upward leaf curling, respectively. Real time PCR analyses revealed a reduction in the levels of the corresponding transgene or endogenous target mRNA. The β-satellite based VIGS vector was able to silence the target genes effectively. Hence, BYVMV β-satellite based VIGS vector can be used in functional genomics studies.
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Affiliation(s)
- C Jeyabharathy
- School of Biotechnology, Madurai Kamaraj University, Department of Plant Biotechnology, Madurai 625021, Tamil Nadu, India
| | - H Shakila
- School of Biotechnology, Madurai Kamaraj University, Department of Plant Biotechnology, Madurai 625021, Tamil Nadu, India
| | - R Usha
- School of Biotechnology, Madurai Kamaraj University, Department of Plant Biotechnology, Madurai 625021, Tamil Nadu, India.
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Zhang JS, Zhao J, Zhang S, He C. Efficient gene silencing mediated by tobacco rattle virus in an emerging model plant physalis. PLoS One 2014; 9:e85534. [PMID: 24454885 PMCID: PMC3891815 DOI: 10.1371/journal.pone.0085534] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 11/28/2013] [Indexed: 12/30/2022] Open
Abstract
The fruit of Physalis has a berry and a novelty called inflated calyx syndrome (ICS, also named the 'Chinese lantern'). Elucidation of the underlying developmental mechanisms of fruit diversity demands an efficient gene functional inference platform. Here, we tested the application of the tobacco rattle virus (TRV)-mediated gene-silencing system in Physalis floridana. First, we characterized the putative gene of a phytoene desaturase in P. floridana (PfPDS). Infecting the leaves of the Physalis seedlings with the PfPDS-TRV vector resulted in a bleached plant, including the developing leaves, floral organs, ICS, berry, and seed. These results indicated that a local VIGS treatment can efficiently induce a systemic mutated phenotype. qRT-PCR analyses revealed that the bleaching extent correlated to the mRNA reduction of the endogenous PfPDS. Detailed comparisons of multiple infiltration and growth protocols allowed us to determine the optimal methodologies for VIGS manipulation in Physalis. We subsequently utilized this optimized VIGS methodology to downregulate the expression of two MADS-box genes, MPF2 and MPF3, and compared the resulting effects with gene-downregulation mediated by RNA interference (RNAi) methods. The VIGS-mediated gene knockdown plants were found to resemble the mutated phenotypes of floral calyx, fruiting calyx and pollen maturation of the RNAi transgenic plants for both MPF2 and MPF3. Moreover, the two MADS-box genes were appeared to have a novel role in the pedicel development in P. floridana. The major advantage of VIGS-based gene knockdown lies in practical aspects of saving time and easy manipulation as compared to the RNAi. Despite the lack of heritability and mosaic mutation phenotypes observed in some organs, the TRV-mediated gene silencing system provides an alternative efficient way to infer gene function in various developmental processes in Physalis, thus facilitating understanding of the genetic basis of the evolution and development of the morphological diversities within the Solanaceae.
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Affiliation(s)
- Ji-Si Zhang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jing Zhao
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Shaohua Zhang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chaoying He
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
- * E-mail:
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Devers EA, Teply J, Reinert A, Gaude N, Krajinski F. An endogenous artificial microRNA system for unraveling the function of root endosymbioses related genes in Medicago truncatula. BMC Plant Biol 2013; 13:82. [PMID: 23679580 PMCID: PMC3679836 DOI: 10.1186/1471-2229-13-82] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 05/10/2013] [Indexed: 05/20/2023]
Abstract
BACKGROUND Legumes have the unique capacity to undergo two important root endosymbioses: the root nodule symbiosis and the arbuscular mycorrhizal symbiosis. Medicago truncatula is widely used to unravel the functions of genes during these root symbioses. Here we describe the development of an artificial microRNA (amiR)-mediated gene silencing system for M. truncatula roots. RESULTS The endogenous microRNA (miR) mtr-miR159b was selected as a backbone molecule for driving amiR expression. Heterologous expression of mtr-miR159b-amiR constructs in tobacco showed that the backbone is functional and mediates an efficient gene silencing. amiR-mediated silencing of a visible marker was also effective after root transformation of M. truncatula constitutively expressing the visible marker. Most importantly, we applied the novel amiR system to shed light on the function of a putative transcription factor, MtErf1, which was strongly induced in arbuscule-containing cells during mycorrhizal symbiosis. MtPt4 promoter driven amiR-silencing led to strongly decreased transcript levels and deformed, non-fully truncated arbuscules indicating that MtErf1 is required for arbuscule development. CONCLUSIONS The endogenous amiR system demonstrated here presents a novel and highly efficient tool to unravel gene functions during root endosymbioses.
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Affiliation(s)
- Emanuel A Devers
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1 14476, Potsdam (OT) Golm, Germany
- Swiss Federal Institute of Technology Zurich, Department of Biology, Zurich, Switzerland
| | - Julia Teply
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1 14476, Potsdam (OT) Golm, Germany
| | - Armin Reinert
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1 14476, Potsdam (OT) Golm, Germany
| | - Nicole Gaude
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1 14476, Potsdam (OT) Golm, Germany
| | - Franziska Krajinski
- Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1 14476, Potsdam (OT) Golm, Germany
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Villanueva-Alonzo HJ, Us-Camas RY, López-Ochoa LA, Robertson D, Guerra-Peraza O, Minero-García Y, Moreno-Valenzuela OA. A new virus-induced gene silencing vector based on Euphorbia mosaic virus-Yucatan peninsula for NPR1 silencing in Nicotiana benthamiana and Capsicum annuum var. Anaheim. Biotechnol Lett 2013; 35:811-23. [PMID: 23546940 DOI: 10.1007/s10529-013-1146-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 01/14/2013] [Indexed: 10/27/2022]
Abstract
Virus-induced gene silencing is based on the sequence-specific degradation of RNA. Here, a gene silencing vector derived from EuMV-YP, named pEuMV-YP:ΔAV1, was used to silence ChlI and NPR1 genes in Nicotiana benthamiana. The silencing of the ChlI transcripts was efficient in the stems, petioles and leaves as reflected in tissue bleaching and reduced transcript levels. The silencing was stable, reaching the flowers and fruits, and was observed throughout the life cycle of the plants. Additionally, the silencing of the NPR1 gene was efficient in both N. benthamiana and Capsicum annuum. After silencing, the plants' viral symptoms increased to levels similar to those seen in wild-type plants. These results suggest that NPR1 plays a role in the compatible interactions of EuMV-YP N. benthamiana and EuMV-C. annum var. anaheim.
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Affiliation(s)
- Hernan J Villanueva-Alonzo
- Unidad de Bioquimica y Biologia Molecular de Plantas, Centro de Investigacion Cientifica de Yucatan AC, Calle 43 No. 130, Chuburna de Hidalgo, C.P. 97200 Merida, Yucatan, Mexico.
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27
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Lange M, Yellina AL, Orashakova S, Becker A. Virus-induced gene silencing (VIGS) in plants: an overview of target species and the virus-derived vector systems. Methods Mol Biol 2013; 975:1-14. [PMID: 23386291 DOI: 10.1007/978-1-62703-278-0_1] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The analysis of gene functions in non-model plant species is often hampered by the fact that stable genetic transformation to downregulate gene expression is laborious and time-consuming, or, for some species, even not achievable. Virus-induced gene silencing (VIGS) can serve as an alternative to mutant collections or stable transgenic plants to allow the characterization of gene functions in a wide range of angiosperm species, albeit in a transient way. VIGS vector systems have been developed from both RNA and DNA plant viral sources to specifically silence target genes in plants. VIGS is nowadays widely used in plant genetics for gene knockdown due to its ease of use and the short time required to generating phenotypes. Here, we summarize successfully targeted eudicot and monocot plant species along with their specific VIGS vector systems which are already available for researchers.
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Affiliation(s)
- Matthias Lange
- Plant Evodevo Group, Justus-Liebig-Universität Gießen, Gießen, Germany
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28
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Abstract
Eggplant (Solanum melongena) is an economically important vegetable requiring investigation into its various genomic functions. The current limitation in the investigation of genomic function in eggplant is the lack of effective tools available for conducting functional assays. Virus-induced gene silencing (VIGS) has played a critical role in the functional genetic analyses. In this paper, TRV-mediated VIGS was successfully elicited in eggplant. We first cloned the CDS sequence of PDS (PHYTOENE DESATURASE) in eggplant and then silenced the PDS gene. Photo-bleaching was shown on the newly-developed leaves four weeks after agroinoculation, indicating that VIGS can be used to silence genes in eggplant. To further illustrate the reliability of VIGS in eggplant, we selected Chl H, Su and CLA1 as reporters to elicit VIGS using the high-pressure spray method. Suppression of Chl H and Su led to yellow leaves, while the depletion of CLA1 resulted in albino. In conclusion, four genes, PDS, Chl H, Su (Sulfur), CLA1, were down-regulated significantly by VIGS, indicating that the VIGS system can be successfully applied in eggplant and is a reliable tool for the study of gene function.
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Affiliation(s)
- Haiping Liu
- Laboratory of Fruit Biology, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China
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29
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Kharazmi S, Behjatnia SAA, Hamzehzarghani H, Niazi A. Cotton leaf curl Multan betasatellite as a plant gene delivery vector trans-activated by taxonomically diverse geminiviruses. Arch Virol 2012; 157:1269-79. [PMID: 22476203 DOI: 10.1007/s00705-012-1290-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 02/14/2012] [Indexed: 10/28/2022]
Abstract
Cotton leaf curl Multan betasatellite (CLCuMB) replicates in tobacco, tomato and datura plants in the presence of the helper viruses tomato leaf curl virus-Australia, Iranian isolates of tomato yellow leaf curl virus, tomato leaf curl Karnataka virus, and beet severe curly top virus (BSCTV). Infectious recombinant CLCuMB constructs were made in which segments of either the CaMV 35S or the petunia ChsA promoter replaced the CLCuMB βC1 ORF, and these were designated pBinβΔC1-35S and pBinβΔC1-ChsA, respectively. Inoculation of tobacco plants containing a functional 35S-GUS transgene with pBinβΔC1-35S, and normal petunia plants with pBinβΔC1-ChsA, in the presence of helper viruses resulted in silencing of GUS and ChsA activities in transgenic tobacco and non-transgenic petunia plants, respectively. Replication of CLCuMB with different geminiviruses, especially BSCTV, a curtovirus with a broad host range, makes it a valuable gene delivery vector to the large number of host plant species of geminiviruses that support CLCuMB.
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Affiliation(s)
- S Kharazmi
- Institute of Biotechnology, Shiraz University, Shiraz, Iran
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30
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Huang C, Qian Y, Li Z, Zhou X. Virus-induced gene silencing and its application in plant functional genomics. Sci China Life Sci 2012; 55:99-108. [PMID: 22415680 DOI: 10.1007/s11427-012-4280-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Accepted: 12/13/2011] [Indexed: 12/13/2022]
Abstract
Virus-induced gene silencing is regarded as a powerful and efficient tool for the analysis of gene function in plants because it is simple, rapid and transformation-free. It has been used to perform both forward and reverse genetics to identify plant functional genes. Many viruses have been developed into virus-induced gene silencing vectors and gene functions involved in development, biotic and abiotic stresses, metabolism, and cellular signaling have been reported. In this review, we discuss the development and application of virus-induced gene silencing in plant functional genomics.
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Affiliation(s)
- Changjun Huang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
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31
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Abstract
Understanding the biology of a system requires the association of gene functions to phenotypes and vice versa. Although a large number of resources and genomic tools are available for studies in the crop plant soybean, investigations related to gene function have been lacking. This is largely due to the fact that rapid functional genomics tools have been unavailable for application in soybean. This constraint was recently alleviated when a novel bean pod mottle virus (BPMV)-based system for virus-induced gene silencing in soybean was developed. This methodology exploits the plant's ability to silence virus-encoded sequences as a defense mechanism. Plants infected with recombinant viruses carrying sequences that are identical/near-identical to the plant's own genes suppress the expression of the target endogenous gene(s). Phenotypes associated with suppression of target sequence enable the assignment of functions to specific genes. The strategy involves inserting short sequences of target soybean genes into the viral genome to generate recombinant vectors. Soybean plants are then inoculated with the recombinant vectors, assessed for BPMV propagation and silencing of the target genes. Plants silenced for specific targets can then be analyzed for various different traits depending upon the known/predicted functions of the target genes. Using this strategy, we have identified genes participating in basal, resistance gene-mediated, and systemic immunity in soybean.
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Affiliation(s)
- Aardra Kachroo
- Department of Plant Pathology, University of Kentucky, Lexington, KY, USA.
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32
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Abstract
Virus-induced gene silencing (VIGS) has emerged as a powerful method for studying gene function. VIGS is induced by infecting a plant with a plant virus that has had its genome modified to include a sequence from the host gene to be silenced. DNAβ and DNA1 are satellite and single-stranded DNA molecules associated with begomoviruses (family Geminiviridae). We converted DNAβ and DNA1 into gene-silencing vectors. The VIGS vectors can induce silencing efficiently in many solanaceous plants. Here, we describe procedures for the use of these two gene-silencing vectors for VIGS in different hosts.
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Affiliation(s)
- Xueping Zhou
- Institute of Biotechnology, Zhejiang University, Hangzhou, China.
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Paprotka T, Deuschle K, Metzler V, Jeske H. Conformation-selective methylation of geminivirus DNA. J Virol 2011; 85:12001-12. [PMID: 21835804 PMCID: PMC3209285 DOI: 10.1128/jvi.05567-11] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 07/29/2011] [Indexed: 12/16/2022] Open
Abstract
Geminiviruses with small circular single-stranded DNA genomes replicate in plant cell nuclei by using various double-stranded DNA (dsDNA) intermediates: distinct open circular and covalently closed circular as well as heterogeneous linear DNA. Their DNA may be methylated partially at cytosine residues, as detected previously by bisulfite sequencing and subsequent PCR. In order to determine the methylation patterns of the circular molecules, the DNAs of tomato yellow leaf curl Sardinia virus (TYLCSV) and Abutilon mosaic virus were investigated utilizing bisulfite treatment followed by rolling circle amplification. Shotgun sequencing of the products yielded a randomly distributed 50% rate of C maintenance after the bisulfite reaction for both viruses. However, controls with unmethylated single-stranded bacteriophage DNA resulted in the same level of C maintenance. Only one short DNA stretch within the C2/C3 promoter of TYLCSV showed hyperprotection of C, with the protection rate exceeding the threshold of the mean value plus 1 standard deviation. Similarly, the use of methylation-sensitive restriction enzymes suggested that geminiviruses escape silencing by methylation very efficiently, by either a rolling circle or recombination-dependent replication mode. In contrast, attempts to detect methylated bases positively by using methylcytosine-specific antibodies detected methylated DNA only in heterogeneous linear dsDNA, and methylation-dependent restriction enzymes revealed that the viral heterogeneous linear dsDNA was methylated preferentially.
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Affiliation(s)
| | - K. Deuschle
- Biologisches Institut, Abteilung für Molekularbiologie und Virologie der Pflanzen, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
| | - V. Metzler
- Biologisches Institut, Abteilung für Molekularbiologie und Virologie der Pflanzen, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
| | - H. Jeske
- Biologisches Institut, Abteilung für Molekularbiologie und Virologie der Pflanzen, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
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34
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Abstract
Virus-induced gene silencing (VIGS) is a technology that exploits an RNA-mediated antivirus defense mechanism in plants and has been shown to have great potential in plant reverse genetics. When the virus vector carries sequences of plant genes, virus infection triggers VIGS that results in the degradation of endogenous mRNAs homologous to the plant genes. The system is well established in Nicotiana benthamiana and several reliable VIGS vectors have been developed for other plant species including important agricultural crops. Here, we describe the use of VIGS technology to determine gene function and plant virus vectors for induction of VIGS in plants.
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35
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Lozano-Durán R, Rosas-Díaz T, Luna AP, Bejarano ER. Identification of host genes involved in geminivirus infection using a reverse genetics approach. PLoS One 2011; 6:e22383. [PMID: 21818318 PMCID: PMC3144222 DOI: 10.1371/journal.pone.0022383] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Accepted: 06/20/2011] [Indexed: 12/17/2022] Open
Abstract
Geminiviruses, like all viruses, rely on the host cell machinery to establish a successful infection, but the identity and function of these required host proteins remain largely unknown. Tomato yellow leaf curl Sardinia virus (TYLCSV), a monopartite geminivirus, is one of the causal agents of the devastating Tomato yellow leaf curl disease (TYLCD). The transgenic 2IRGFP N. benthamiana plants, used in combination with Virus Induced Gene Silencing (VIGS), entail an important potential as a tool in reverse genetics studies to identify host factors involved in TYLCSV infection. Using these transgenic plants, we have made an accurate description of the evolution of TYLCSV replication in the host in both space and time. Moreover, we have determined that TYLCSV and Tobacco rattle virus (TRV) do not dramatically influence each other when co-infected in N. benthamiana, what makes the use of TRV-induced gene silencing in combination with TYLCSV for reverse genetic studies feasible. Finally, we have tested the effect of silencing candidate host genes on TYLCSV infection, identifying eighteen genes potentially involved in this process, fifteen of which had never been implicated in geminiviral infections before. Seven of the analyzed genes have a potential anti-viral effect, whereas the expression of the other eleven is required for a full infection. Interestingly, almost half of the genes altering TYLCSV infection play a role in postranslational modifications. Therefore, our results provide new insights into the molecular mechanisms underlying geminivirus infections, and at the same time reveal the 2IRGFP/VIGS system as a powerful tool for functional reverse genetics studies.
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Affiliation(s)
- Rosa Lozano-Durán
- Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Departamento Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Teatinos, Málaga, Spain
| | - Tábata Rosas-Díaz
- Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Departamento Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Teatinos, Málaga, Spain
| | - Ana P. Luna
- Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Departamento Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Teatinos, Málaga, Spain
| | - Eduardo R. Bejarano
- Málaga-Consejo Superior de Investigaciones Científicas (IHSM-UMA-CSIC), Departamento Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Teatinos, Málaga, Spain
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36
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Shimura H, Pantaleo V, Ishihara T, Myojo N, Inaba JI, Sueda K, Burgyán J, Masuta C. A viral satellite RNA induces yellow symptoms on tobacco by targeting a gene involved in chlorophyll biosynthesis using the RNA silencing machinery. PLoS Pathog 2011; 7:e1002021. [PMID: 21573143 PMCID: PMC3088725 DOI: 10.1371/journal.ppat.1002021] [Citation(s) in RCA: 214] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 02/23/2011] [Indexed: 12/25/2022] Open
Abstract
Symptoms on virus-infected plants are often very specific to the given virus. The molecular mechanisms involved in viral symptom induction have been extensively studied, but are still poorly understood. Cucumber mosaic virus (CMV) Y satellite RNA (Y-sat) is a non-coding subviral RNA and modifies the typical symptom induced by CMV in specific hosts; Y-sat causes a bright yellow mosaic on its natural host Nicotiana tabacum. The Y-sat-induced yellow mosaic failed to develop in the infected Arabidopsis and tomato plants suggesting a very specific interaction between Y-sat and its host. In this study, we revealed that Y-sat produces specific short interfering RNAs (siRNAs), which interfere with a host gene, thus inducing the specific symptom. We found that the mRNA of tobacco magnesium protoporphyrin chelatase subunit I (ChlI, the key gene involved in chlorophyll synthesis) had a 22-nt sequence that was complementary to the Y-sat sequence, including four G-U pairs, and that the Y-sat-derived siRNAs in the virus-infected plant downregulate the mRNA of ChlI by targeting the complementary sequence. ChlI mRNA was also downregulated in the transgenic lines that express Y-sat inverted repeats. Strikingly, modifying the Y-sat sequence in order to restore the 22-nt complementarity to Arabidopsis and tomato ChlI mRNA resulted in yellowing symptoms in Y-sat-infected Arabidopsis and tomato, respectively. In 5'-RACE experiments, the ChlI transcript was cleaved at the expected middle position of the 22-nt complementary sequence. In GFP sensor experiments using agroinfiltration, we further demonstrated that Y-sat specifically targeted the sensor mRNA containing the 22-nt complementary sequence of ChlI. Our findings provide direct evidence that the identified siRNAs derived from viral satellite RNA directly modulate the viral disease symptom by RNA silencing-based regulation of a host gene.
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MESH Headings
- Arabidopsis/genetics
- Arabidopsis/virology
- Base Sequence
- Capsicum/genetics
- Capsicum/virology
- Chlorophyll/biosynthesis
- Chlorophyll/genetics
- Cucumber Mosaic Virus Satellite/genetics
- Cucumber Mosaic Virus Satellite/metabolism
- Cucumovirus/metabolism
- Cucumovirus/pathogenicity
- Down-Regulation
- Gene Expression Regulation, Plant
- Genes, Plant
- Host-Pathogen Interactions
- Lyases/genetics
- Lyases/metabolism
- Solanum lycopersicum/genetics
- Solanum lycopersicum/virology
- Molecular Sequence Data
- Phenotype
- Plant Diseases/genetics
- Plant Diseases/virology
- Plants, Genetically Modified/enzymology
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/virology
- RNA Interference
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Nicotiana/enzymology
- Nicotiana/genetics
- Nicotiana/virology
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Affiliation(s)
- Hanako Shimura
- Research Faculty of Agriculture, Hokkaido
University, Kita-ku, Sapporo, Japan
| | | | - Takeaki Ishihara
- Research Faculty of Agriculture, Hokkaido
University, Kita-ku, Sapporo, Japan
| | - Nobutoshi Myojo
- Research Faculty of Agriculture, Hokkaido
University, Kita-ku, Sapporo, Japan
| | - Jun-ichi Inaba
- Research Faculty of Agriculture, Hokkaido
University, Kita-ku, Sapporo, Japan
| | - Kae Sueda
- Research Faculty of Agriculture, Hokkaido
University, Kita-ku, Sapporo, Japan
| | | | - Chikara Masuta
- Research Faculty of Agriculture, Hokkaido
University, Kita-ku, Sapporo, Japan
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Pasumarthy KK, Mukherjee SK, Choudhury NR. The presence of tomato leaf curl Kerala virus AC3 protein enhances viral DNA replication and modulates virus induced gene-silencing mechanism in tomato plants. Virol J 2011; 8:178. [PMID: 21496351 PMCID: PMC3102638 DOI: 10.1186/1743-422x-8-178] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 04/18/2011] [Indexed: 12/21/2022] Open
Abstract
Background Geminiviruses encode few viral proteins. Most of the geminiviral proteins are multifunctional and influence various host cellular processes for the successful viral infection. Though few viral proteins like AC1 and AC2 are well characterized for their multiple functions, role of AC3 in the successful viral infection has not been investigated in detail. Results We performed phage display analysis with the purified recombinant AC3 protein with Maltose Binding Protein as fusion tag (MBP-AC3). Putative AC3 interacting peptides identified through phage display were observed to be homologous to peptides of proteins from various metabolisms. We grouped these putative AC3 interacting peptides according to the known metabolic function of the homologous peptide containing proteins. In order to check if AC3 influences any of these particular metabolic pathways, we designed vectors for assaying DNA replication and virus induced gene-silencing of host gene PCNA. Investigation with these vectors indicated that AC3 enhances viral replication in the host plant tomato. In the PCNA gene-silencing experiment, we observed that the presence of functional AC3 ORF strongly manifested the stunted phenotype associated with the virus induced gene-silencing of PCNA in tomato plants. Conclusions Through the phage display analysis proteins from various metabolic pathways were identified as putative AC3 interacting proteins. By utilizing the vectors developed, we could analyze the role of AC3 in viral DNA replication and host gene-silencing. Our studies indicate that AC3 is also a multifunctional protein.
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Affiliation(s)
- Kalyan K Pasumarthy
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi-110067, India
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38
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Abstract
Virus-induced gene silencing (VIGS) provides an attractive tool for high-throughput analysis of the functional effects of gene knockdown. Virus genomes are engineered to include fragments of target host genes, and the infected plant recognizes and silences the target genes as part of its viral defense mechanism. The consequences of gene inactivation, even of key metabolic, regulatory, or embryo-lethal genes, can thus be readily analyzed. A number of viral vectors have been developed for VIGS; one of the most frequently employed is based on tobacco rattle virus (TRV) due to its wide host range, efficiency, ease of application, and limited disease symptoms. TRV-based VIGS comprises two vectors. One (RNA2) includes a multiple cloning site into which fragments of target genes can be inserted. We have shown that the TRV/VIGS system can simultaneously silence as many as five independent genes. TRV is a mosaic-type virus, and silencing also occurs in a mosaic pattern. It is therefore desirable to have a reporter that can show where target genes have been silenced. The photobleaching induced by silencing phytoene desaturase (PDS) and the loss of purple pigmentation induced by silencing chalcone synthase (CHS) have successfully been used to indicate the location of coordinate silencing of other target genes. In this chapter, we outline our protocols for the use of VIGS for analysis of gene function, focusing particularly on the use of TRV with petunia and tomato.
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Affiliation(s)
- Cai-Zhong Jiang
- Crops Pathology and Genetics Research Unit, USDA-ARS, Davis, CA, USA.
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39
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Abstract
One of the main post-genomics challenges facing scientists remains the identification of gene function in a large number of plant species. Plant viruses offer great potential in linking genes to phenotypes through epigenetic expression or knockdown of selected genes. The past decade has seen the development and ever increasing applications of a gene knockdown technique termed virus-induced gene silencing (VIGS). VIGS recapitulates an RNA-mediated antiviral defense mechanism, mediating a homology-based post-transcriptional degradation of selected plant RNAs, leading to a loss-of-function phenotype. Due to its rapidity and increasing number of virus vectors developed as gene silencing platforms, VIGS has become a powerful technology to determine the function of genes in an increasing number of crop species, where the routinely available transgenesis or mutagenesis approaches are often not amenable to large genomes and complex genetic backgrounds.
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Affiliation(s)
- Christophe Lacomme
- Virology and Zoology Section, Science and Advice for Scottish Agriculture (SASA), Roddinglaw Road, Edinburgh, EH12 9FJ, UK,
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Krenz B, Wege C, Jeske H. Cell-free construction of disarmed Abutilon mosaic virus-based gene silencing vectors. J Virol Methods 2010; 169:129-37. [PMID: 20638413 DOI: 10.1016/j.jviromet.2010.07.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 07/06/2010] [Accepted: 07/12/2010] [Indexed: 11/20/2022]
Abstract
The bipartite Abutilon mosaic virus (AbMV) was engineered as a versatile silencing vector in which the coat protein gene of DNA A was deleted and replaced by sequences of interest. Plants transgenic for the dimeric AbMV DNA B component were used as test hosts to minimize the risk of unintended release of the recombinant DNA. The vector construct was stable genetically upon systemic infection and, in common with the parental virus, the vector remained phloem-limited. For virus-induced gene silencing (VIGS), a phytoene desaturase gene fragment was isolated from Nicotiana benthamiana (NbPDS) and inserted into the vector. After agroinfection, phytoene desaturase silencing was triggered efficiently in all leaf tissues without interference by viral symptoms. In order to facilitate further the use of the system, a technique for cell-free construction of recombinants was established using rolling circle amplification and biolistic inoculation of DNA B-transgenic plants. This novel procedure provides a convenient and safe way for delivering VIGS constructs for functional genomics.
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Affiliation(s)
- Björn Krenz
- University of Stuttgart, Department of Molecular Biology and Plant Virology, Pfaffenwaldring 57, D-70550 Stuttgart, Germany
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Abstract
Virus-induced gene silencing (VIGS) exploits endogenous plant antiviral defense mechanisms to posttranscriptionally silence the expression of targeted plant genes. VIGS is quick and relatively easy to perform and therefore serves as a powerful tool for high-throughput functional genomics in plants. Combined with the use of subtractive cDNA libraries for generating a collection of VIGS-ready cDNA inserts, VIGS can be utilized to screen a large number of genes to determine phenotypes resulting from the knockdown/knockout of gene function. Taking into account the optimal insert design for VIGS, we describe a methodology for producing VIGS-ready cDNA libraries enriched for inserts relevant to the biological process of interest.
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Affiliation(s)
- Andrea T Todd
- NRC Plant Biotechnology Institute, Saskatoon, SK, Canada
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Abstract
Reverse genetics has proven to be a powerful approach to elucidating gene function in plants, particularly in Arabidopsis. Virus-induced gene silencing (VIGS) is one such method and achieves reductions in target gene expression as the vector moves into newly formed tissues of inoculated plants. VIGS is especially useful for plants that are recalcitrant for transformation and for genes that cause embryo lethality. VIGS provides rapid, transient knockdowns as a complement to other reverse genetics tools and can be used to screen sequences for RNAi prior to stable transformation. High-throughput, forward genetic screening is also possible by cloning libraries of short gene fragments directly into a VIGS plasmid DNA vector, inoculating, and then looking for a phenotype of interest. VIGS is especially useful for studying genes in crop species, which currently have few genetic resources. VIGS facilitates a rapid comparison of knockdown phenotypes of the same gene in different breeding lines or mutant backgrounds, as the same vector is easily inoculated into different plants. In this chapter, we briefly discuss how to choose or construct a VIGS vector and then how to design and carry out effective experiments using VIGS.
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Golenberg EM, Sather DN, Hancock LC, Buckley KJ, Villafranco NM, Bisaro DM. Development of a gene silencing DNA vector derived from a broad host range geminivirus. Plant Methods 2009; 5:9. [PMID: 19573239 PMCID: PMC2713212 DOI: 10.1186/1746-4811-5-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Accepted: 07/02/2009] [Indexed: 05/03/2023]
Abstract
BACKGROUND Gene silencing is proving to be a powerful tool for genetic, developmental, and physiological analyses. The use of viral induced gene silencing (VIGS) offers advantages to transgenic approaches as it can be potentially applied to non-model systems for which transgenic techniques are not readily available. However, many VIGS vectors are derived from Gemini viruses that have limited host ranges. We present a new, unipartite vector that is derived from a curtovirus that has a broad host range and will be amenable to use in many non-model systems. RESULTS The construction of a gene silencing vector derived from the geminivirus Beet curly top virus (BCTV), named pWSRi, is reported. Two versions of the vector have been developed to allow application by biolistic techniques or by agro-infiltration. We demonstrate its ability to silence nuclear genes including ribulose bisphosphate carboxylase small subunit (rbcS), transketolase, the sulfur allele of magnesium chelatase (ChlI), and two homeotic transcription factors in spinach or tomato by generating gene-specific knock-down phenotypes. Onset of phenotypes occurred 3 to 12 weeks post-inoculation, depending on the target gene, in organs that developed after the application. The vector lacks movement genes and we found no evidence for significant spread from the site of inoculation. However, viral amplification in inoculated tissue was detected and is necessary for systemic silencing, suggesting that signals generated from active viral replicons are efficiently transported within the plant. CONCLUSION The unique properties of the pWSRi vector, the ability to silence genes in meristem tissue, the separation of virus and silencing phenotypes, and the broad natural host range of BCTV, suggest that it will have wide utility.
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Affiliation(s)
- Edward M Golenberg
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - D Noah Sather
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
- Seattle Biomedical Research Institute, 307 Westlake Ave. N., Seattle, WA 98109, USA
| | - Leandria C Hancock
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
- Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, 3901 Rainbow Boulevard, MS1053, G017 Lied Building, Kansas City, KS 66160, USA
| | - Kenneth J Buckley
- Department of Molecular Genetics and Plant Biotechnology Center, The Ohio State University, Columbus, OH 43210, USA
| | - Natalie M Villafranco
- Department of Molecular Genetics and Plant Biotechnology Center, The Ohio State University, Columbus, OH 43210, USA
| | - David M Bisaro
- Department of Molecular Genetics and Plant Biotechnology Center, The Ohio State University, Columbus, OH 43210, USA
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Abstract
The I subunit of magnesium-chelatase (CHLI) is encoded by two genes in Arabidopsis (Arabidopsis thaliana), CHLI1 and CHLI2. Conflicting results have been reported concerning the functions of the two proteins. We show here that the chli1/chli1 chli2/chli2 double knockout mutant was albino. Comparison with the pale-green phenotype of a chli1/chli1 single knockout mutant indicates that CHLI2 could support some chlorophyll biosynthesis in the complete absence of CHLI1. Real-time quantitative reverse transcription-polymerase chain reaction showed that CHLI2 was expressed at a much lower level than CHLI1. The chli1/chli1 chli2/chli2 double mutant could be fully rescued by expressing a transgene of CHLI2 driven by the CHLI1 promoter. These results suggest that differences between CHLI1 and CHLI2 lie mostly in their expression levels. Furthermore, both the chli1/chli1 and chli2/chli2 single knockout mutants had lower survival rates during de-etiolation than the wild type, suggesting that both genes are required for optimal growth during de-etiolation. In addition, we show that a semidominant chli1 mutant allele and the chli1/chli1 chli2/chli2 double mutant accumulated Lhcb1 transcripts when treated with the herbicide norflurazon, indicating that knocking out the CHLI activity causes the genome-uncoupled phenotype.
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Affiliation(s)
- Yi-Shiuan Huang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan
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Buchmann RC, Asad S, Wolf JN, Mohannath G, Bisaro DM. Geminivirus AL2 and L2 proteins suppress transcriptional gene silencing and cause genome-wide reductions in cytosine methylation. J Virol 2009; 83:5005-13. [PMID: 19279102 PMCID: PMC2682068 DOI: 10.1128/jvi.01771-08] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Accepted: 02/24/2009] [Indexed: 12/31/2022] Open
Abstract
Geminiviruses replicate single-stranded DNA genomes through double-stranded intermediates that associate with cellular histone proteins. Unlike RNA viruses, they are subject to RNA-directed methylation pathways that target viral chromatin and likely lead to transcriptional gene silencing (TGS). Here we present evidence that the related geminivirus proteins AL2 and L2 are able to suppress this aspect of host defense. AL2 and L2 interact with and inactivate adenosine kinase (ADK), which is required for efficient production of S-adenosyl methionine, an essential methyltransferase cofactor. We demonstrate that the viral proteins can reverse TGS of a green fluorescent protein (GFP) transgene in Nicotiana benthamiana when overexpressed from a Potato virus X vector and that reversal of TGS by geminiviruses requires L2 function. We also show that AL2 and L2 cause ectopic expression of endogenous Arabidopsis thaliana loci silenced by methylation in a manner that correlates with ADK inhibition. However, at one exceptional locus, ADK inhibition was insufficient and TGS reversal required the transcriptional activation domain of AL2. Using restriction-sensitive PCR and bisulfite sequencing, we showed that AL2-mediated TGS suppression is accompanied by reduced cytosine methylation. Finally, using a methylation-sensitive single-nucleotide extension assay, we showed that transgenic expression of AL2 or L2 causes global reduction in cytosine methylation. Our results provide further evidence that viral chromatin methylation is an important host defense and allow us to propose that as a countermeasure, geminivirus proteins reverse TGS by nonspecifically inhibiting cellular transmethylation reactions. To our knowledge, this is the first report that viral proteins can inhibit TGS.
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Affiliation(s)
- R Cody Buchmann
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA
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Abstract
Virus-induced gene silencing (VIGS) is currently recognized as a powerful reverse genetics tool for application in functional genomics. DNA1, a satellite-like and single-stranded DNA molecule associated with begomoviruses (Family Geminiviridae), has been shown to replicate autonomously but requires the helper virus for its dissemination. We developed a VIGS vector based on the DNA1 component of tobacco curly shoot virus (TbCSV), a monopartite begomovirus, by inserting a multiple cloning site between the replication-associated protein open reading frame and the A-rich region for subsequent insertion of DNA fragments of genes targeted for silencing. When a host gene (sulphur, Su) or transgene (green fluorescent protein, GFP) was inserted into the modified DNA1 vector and co-agroinoculated with TbCSV, efficient silencing of the cognate gene was observed in Nicotiana benthamiana plants. More interestingly, we demonstrated that this modified DNA1 could effectively suppress GFP in transgenic N. benthamiana or endogenous Su in tobacco plants when co-agroinoculated with tomato yellow leaf curl China virus (TYLCCNV), another monopartite begomovirus that does not induce any viral symptoms. A gene-silencing system in Nicotiana spp., Solanum lycopersicum and Petunia hybrida plants was then established using TYLCCNV and the modified DNA1 vector. The system can be used to silence genes involved in meristem and flower development. The modified DNA1 vector was used to silence the AtTOM homologous genes (NbTOM1 and NbTOM3) in N. benthamiana. Silencing of NbTOM1 or NbTOM3 can reduce tobamovirus multiplication to a lower level, and silencing of both genes simultaneously can completely inhibit tobamovirus multiplication. Previous studies have reported that DNA1 is associated with both monopartite and bipartite begomoviruses, as well as curtoviruses. This vector system can therefore be applied for the study, analysis and discovery of gene function in a variety of important crop plants.
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Affiliation(s)
- Changjun Huang
- Statel Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310029, China
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48
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Abstract
Plant pathogenic geminiviruses have been proliferating worldwide and have, therefore, attracted considerable scientific interest during the past three decades. Current knowledge concerning their virion and genome structure, their molecular biology of replication, recombination, transcription, and silencing, as well as their transport through plants and dynamic competition with host responses are summarized. The topics are chosen to provide a comprehensive introduction for animal virologists, emphasizing similarities and differences to the closest functional relatives, polyomaviruses and circoviruses.
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49
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Unver T, Budak H. Virus-induced gene silencing, a post transcriptional gene silencing method. Int J Plant Genomics 2009; 2009:198680. [PMID: 19547658 PMCID: PMC2699436 DOI: 10.1155/2009/198680] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 03/30/2009] [Indexed: 05/02/2023]
Abstract
Virus-induced gene silencing (VIGS) is one of the reverse genetics tools for analysis of gene function that uses viral vectors carrying a target gene fragment to produce dsRNA which trigger RNA-mediated gene silencing. There are a number of viruses which have been modified to silence the gene of interest effectively with a sequence-specific manner. Therefore, different types of methodologies have been advanced and modified for VIGS approach. Virus-derived inoculations are performed on host plants using different methods such as agro-infiltration and in vitro transcriptions. VIGS has many advantages compared to other loss-of-gene function approaches. The approach provides the generation of rapid phenotype and no need for plant transformation. The cost of VIGS experiment is relatively low, and large-scale analysis of screening studies can be achieved by the VIGS. However, there are still limitations of VIGS to be overcome. Nowadays, many virus-derived vectors are optimized to silence more than one host plant such as TRV-derived viral vectors which are used for Arabidopsis and Nicothiana benthamiana. By development of viral silencing systems monocot plants can also be targeted as silencing host in addition to dicotyledonous plants. For instance, Barley stripe mosaic virus (BSMV)-mediated VIGS allows silencing of barley and wheat genes. Here we summarize current protocols and recent modified viral systems to lead silencing of genes in different host species.
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Affiliation(s)
- Turgay Unver
- Biological Sciences & Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Orhanli, Tuzla, Turkey
- Kocaeli University, Arslanbey MYO, Izmit, Turkey
| | - Hikmet Budak
- Biological Sciences & Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Orhanli, Tuzla, Turkey
- *Hikmet Budak:
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Miller JA, Witherow DS, Carson S. A laboratory-intensive course on RNA interference and model organisms. CBE Life Sci Educ 2009; 8:316-25. [PMID: 19952100 PMCID: PMC2786282 DOI: 10.1187/cbe.09-02-0012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Accepted: 07/16/2009] [Indexed: 05/19/2023]
Abstract
RNA interference (RNAi) is a powerful method to silence gene expression in a variety of organisms and is generating interest not only as a useful tool for research scientists but also as a novel class of therapeutics in clinical trials. Here, we report that undergraduate and graduate students with a basic molecular biology background were able to demonstrate conceptual knowledge and technical skills for using RNAi as a research tool upon completion of an intensive 8-wk RNAi course with a 2-h lecture and 5-h laboratory per week. Students were instructed on design of RNAi experiments in model organisms and perform multiweek laboratory sessions based on journal articles read and discussed in class. Using Nicotiana benthamiana, Caenorhabditis elegans, and mammalian cell culture, students analyzed the extent of silencing using both qualitative assessment of phenotypic variations and quantitative measurements of RNA levels or protein levels. We evaluated the course over two semesters, each with a separate instructor. In both semesters, we show students met expected learning outcomes as demonstrated by successful laboratory experiment results, as well as positive instructor assessments of exams and lab reports. Student self-assessments revealed increased confidence in conceptual knowledge and practical skills. Our data also suggest that the course is adaptable to different instructors with varying expertise.
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Affiliation(s)
| | - D. Scott Witherow
- Biotechnology Program and Department of Plant Biology, North Carolina State University, Raleigh, NC 27695
| | - Susan Carson
- Biotechnology Program and Department of Plant Biology, North Carolina State University, Raleigh, NC 27695
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