1
|
Tselika M, Belmezos N, Kallemi P, Andronis C, Chiumenti M, Navarro B, Lavigne M, Di Serio F, Kalantidis K, Katsarou K. PSTVd infection in Nicotiana benthamiana plants has a minor yet detectable effect on CG methylation. FRONTIERS IN PLANT SCIENCE 2023; 14:1258023. [PMID: 38023875 PMCID: PMC10645062 DOI: 10.3389/fpls.2023.1258023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/13/2023] [Indexed: 12/01/2023]
Abstract
Viroids are small circular RNAs infecting a wide range of plants. They do not code for any protein or peptide and therefore rely on their structure for their biological cycle. Observed phenotypes of viroid infected plants are thought to occur through changes at the transcriptional/translational level of the host. A mechanism involved in such changes is RNA-directed DNA methylation (RdDM). Till today, there are contradictory works about viroids interference of RdDM. In this study, we investigated the epigenetic effect of viroid infection in Nicotiana benthamiana plants. Using potato spindle tuber viroid (PSTVd) as the triggering pathogen and via bioinformatic analyses, we identified endogenous gene promoters and transposable elements targeted by 24 nt host siRNAs that differentially accumulated in PSTVd-infected and healthy plants. The methylation status of these targets was evaluated following digestion with methylation-sensitive restriction enzymes coupled with PCR amplification, and bisulfite sequencing. In addition, we used Methylation Sensitive Amplification Polymorphism (MSAP) followed by sequencing (MSAP-seq) to study genomic DNA methylation of 5-methylcytosine (5mC) in CG sites upon viroid infection. In this study we identified a limited number of target loci differentially methylated upon PSTVd infection. These results enhance our understanding of the epigenetic host changes as a result of pospiviroid infection.
Collapse
Affiliation(s)
- Martha Tselika
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
| | | | - Paraskevi Kallemi
- Department of Biology, University of Crete, Heraklion, Crete, Greece
| | - Christos Andronis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
| | - Michela Chiumenti
- Istituto per la Protezione Sostenibile delle Piante, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Beatriz Navarro
- Istituto per la Protezione Sostenibile delle Piante, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Matthieu Lavigne
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
| | - Francesco Di Serio
- Istituto per la Protezione Sostenibile delle Piante, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Kriton Kalantidis
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
| | - Konstantina Katsarou
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Crete, Greece
| |
Collapse
|
2
|
Liu S, Han Y, Li WX, Ding SW. Infection Defects of RNA and DNA Viruses Induced by Antiviral RNA Interference. Microbiol Mol Biol Rev 2023; 87:e0003522. [PMID: 37052496 PMCID: PMC10304667 DOI: 10.1128/mmbr.00035-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023] Open
Abstract
Immune recognition of viral genome-derived double-stranded RNA (dsRNA) molecules and their subsequent processing into small interfering RNAs (siRNAs) in plants, invertebrates, and mammals trigger specific antiviral immunity known as antiviral RNA interference (RNAi). Immune sensing of viral dsRNA is sequence-independent, and most regions of viral RNAs are targeted by virus-derived siRNAs which extensively overlap in sequence. Thus, the high mutation rates of viruses do not drive immune escape from antiviral RNAi, in contrast to other mechanisms involving specific virus recognition by host immune proteins such as antibodies and resistance (R) proteins in mammals and plants, respectively. Instead, viruses actively suppress antiviral RNAi at various key steps with a group of proteins known as viral suppressors of RNAi (VSRs). Some VSRs are so effective in virus counter-defense that potent inhibition of virus infection by antiviral RNAi is undetectable unless the cognate VSR is rendered nonexpressing or nonfunctional. Since viral proteins are often multifunctional, resistance phenotypes of antiviral RNAi are accurately defined by those infection defects of VSR-deletion mutant viruses that are efficiently rescued by host deficiency in antiviral RNAi. Here, we review and discuss in vivo infection defects of VSR-deficient RNA and DNA viruses resulting from the actions of host antiviral RNAi in model systems.
Collapse
Affiliation(s)
- Si Liu
- Department of Microbiology & Plant Pathology, University of California, Riverside, California, USA
- Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
| | - Yanhong Han
- Vector-borne Virus Research Center, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Wan-Xiang Li
- Department of Microbiology & Plant Pathology, University of California, Riverside, California, USA
- Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
| | - Shou-Wei Ding
- Department of Microbiology & Plant Pathology, University of California, Riverside, California, USA
- Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
| |
Collapse
|
3
|
Ding SW. Transgene Silencing, RNA Interference, and the Antiviral Defense Mechanism Directed by Small Interfering RNAs. PHYTOPATHOLOGY 2023; 113:616-625. [PMID: 36441873 DOI: 10.1094/phyto-10-22-0358-ia] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
One important discovery in plant pathology over recent decades is the natural antiviral defense mechanism mediated by RNA interference (RNAi). In antiviral RNAi, virus infection triggers Dicer processing of virus-specific double-stranded RNA into small interfering RNAs (siRNAs). Frequently, further amplified by host enzyme and cofactors, these virus-derived siRNAs direct specific virus clearance in an Argonaute protein-containing effector complex. The siRNAs derived from viruses and viroids accumulate to very high levels during infection. Because they overlap extensively in nucleotide sequence, this allows for deep sequencing and bioinformatics assembly of total small RNAs for rapid discovery and identification of viruses and viroids. Antiviral RNAi acts as the primary defense mechanism against both RNA and DNA viruses in plants, yet viruses still successfully infect plants. They do so because all currently recognized plant viruses combat the RNAi response by encoding at least one protein as a viral suppressor of RNAi (VSR) required for infection, even though plant viruses have small genome sizes with a limited coding capacity. This review article will recapitulate the key findings that have revealed the genetic pathway for the biogenesis and antiviral activity of viral siRNAs and the specific role of VSRs in infection by antiviral RNAi suppression. Moreover, early pioneering studies on transgene silencing, RNAi, and virus-plant/virus-virus interactions paved the road to the discovery of antiviral RNAi.
Collapse
Affiliation(s)
- Shou-Wei Ding
- Department of Microbiology & Plant Pathology and Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA
| |
Collapse
|
4
|
Maksimov IV, Shein MY, Burkhanova GF. RNA Interference in Plant Protection from Fungal and Oomycete Infection. APPL BIOCHEM MICRO+ 2022. [DOI: 10.1134/s0003683822100106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
|
5
|
Shi M, Wang C, Wang P, Zhang M, Liao W. Methylation in DNA, histone, and RNA during flowering under stress condition: A review. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 324:111431. [PMID: 36028071 DOI: 10.1016/j.plantsci.2022.111431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/07/2022] [Accepted: 08/19/2022] [Indexed: 06/15/2023]
Abstract
Flowering is the most critical transition period in the whole lifecycle of plants, and it is a highly sensitive period to stress. New combinations of temperature, drought stress, carbon dioxide and other abiotic/biotic conditions resulting from contemporary climate change affect the flowering process. Plants have evolved several strategies to deal with environmental stresses, including epigenetic modifications. Numerous studies show that environmental stresses trigger methylation/demethylation during flowering to preserve/accelerate plant lifecycle. What's more, histone and DNA methylation can be induced to respond to stresses, resulting in changes of flowering gene expression and enhancing stress tolerance in plants. Furthermore, RNA methylation may influence stress-regulated flowering by regulating mRNA stability and antioxidant mechanism. Our review presents the involvement of methylation in stress-repressed and stress-induced flowering. The crosstalk between methylation and small RNAs, phytohormones and exogenous substances (such as salicylic acid, nitric oxide) during flowering under different stresses were discussed. The latest regulatory evidence of RNA methylation in stress-regulated flowering was collected for the first time. Meanwhile, the limited evidences of methylation in biotic stress-induced flowering were summarized. Thus, the review provides insights into understanding of methylation mechanism in stress-regulated flowering and makes use for the development of regulating plant flowering at epigenetic level in the future.
Collapse
Affiliation(s)
- Meimei Shi
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China
| | - Chunlei Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China
| | - Peng Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China
| | - Meiling Zhang
- College of Science, Gansu Agricultural University, Lanzhou 730070, China
| | - Weibiao Liao
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| |
Collapse
|
6
|
Arora H, Singh RK, Sharma S, Sharma N, Panchal A, Das T, Prasad A, Prasad M. DNA methylation dynamics in response to abiotic and pathogen stress in plants. PLANT CELL REPORTS 2022; 41:1931-1944. [PMID: 35833989 DOI: 10.1007/s00299-022-02901-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
DNA methylation is a dynamic epigenetic mechanism that plays a significant role in gene expression and also maintains chromatin stability. The process is conserved in both plants and animals, and crucial for development and stress responses. Differential DNA methylation during adverse environmental conditions or pathogen attack facilitates the selective expression of defense-related genes. Both stress-induced DNA hypomethylation and hypermethylation play beneficial roles in activating the defense response. These DNA marks may be carried to the next generation making the progenies 'primed' for abiotic and biotic stress responses. Over the recent years, rapid advancements in the area of high throughput sequencing have enabled the detection of methylation status at genome levels in several plant species. Epigenotyping offers an alternative tool to plant breeders in addition to conventional markers for the selection of the desired offspring. In this review, we briefly discuss the mechanism of DNA methylation, recent understanding of DNA methylation-mediated gene regulation during abiotic and biotic stress responses, and stress memory in plants.
Collapse
Affiliation(s)
- Heena Arora
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Roshan Kumar Singh
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Shambhavi Sharma
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Namisha Sharma
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
- Institute of Life Sciences, NALCO Nagar, Bhubaneswar, 751023, India
| | - Anurag Panchal
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Tuhin Das
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Ashish Prasad
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Manoj Prasad
- National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India.
- Department of Plant Sciences, University of Hyderabad, Hyderabad, Telangana, 500046, India.
| |
Collapse
|
7
|
Rössner C, Lotz D, Becker A. VIGS Goes Viral: How VIGS Transforms Our Understanding of Plant Science. ANNUAL REVIEW OF PLANT BIOLOGY 2022; 73:703-728. [PMID: 35138878 DOI: 10.1146/annurev-arplant-102820-020542] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Virus-induced gene silencing (VIGS) has developed into an indispensable approach to gene function analysis in a wide array of species, many of which are not amenable to stable genetic transformation. VIGS utilizes the posttranscriptional gene silencing (PTGS) machinery of plants to restrain viral infections systemically and is used to downregulate the plant's endogenous genes. Here, we review the molecular mechanisms of DNA- and RNA-virus-based VIGS, its inherent connection to PTGS, and what is known about the systemic spread of silencing. Recently, VIGS-based technologies have been expanded to enable not only gene silencing but also overexpression [virus-induced overexpression (VOX)], genome editing [virus-induced genome editing (VIGE)], and host-induced gene silencing (HIGS). These techniques expand the genetic toolbox for nonmodel organisms even more. Further, we illustrate the versatility of VIGS and the methods derived from it in elucidating molecular mechanisms, using tomato fruit ripening and programmed cell death as examples. Finally, we discuss challenges of and future perspectives on the use of VIGS to advance gene function analysis in nonmodel plants in the postgenomic era.
Collapse
Affiliation(s)
- Clemens Rössner
- Institute of Botany, Justus-Liebig University Gießen, Gießen, Germany;
| | - Dominik Lotz
- Institute of Botany, Justus-Liebig University Gießen, Gießen, Germany;
| | - Annette Becker
- Institute of Botany, Justus-Liebig University Gießen, Gießen, Germany;
| |
Collapse
|
8
|
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] [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.
Collapse
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
| |
Collapse
|
9
|
Veluthambi K, Sunitha S. Targets and Mechanisms of Geminivirus Silencing Suppressor Protein AC2. Front Microbiol 2021; 12:645419. [PMID: 33897657 PMCID: PMC8062710 DOI: 10.3389/fmicb.2021.645419] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/10/2021] [Indexed: 11/13/2022] Open
Abstract
Geminiviruses are plant DNA viruses that infect a wide range of plant species and cause significant losses to economically important food and fiber crops. The single-stranded geminiviral genome encodes a small number of proteins which act in an orchestrated manner to infect the host. The fewer proteins encoded by the virus are multifunctional, a mechanism uniquely evolved by the viruses to balance the genome-constraint. The host-mediated resistance against incoming virus includes post-transcriptional gene silencing, transcriptional gene silencing, and expression of defense responsive genes and other cellular regulatory genes. The pathogenicity property of a geminiviral protein is linked to its ability to suppress the host-mediated defense mechanism. This review discusses what is currently known about the targets and mechanism of the viral suppressor AC2/AL2/transcriptional activator protein (TrAP) and explore the biotechnological applications of AC2.
Collapse
Affiliation(s)
- Karuppannan Veluthambi
- Department of Plant Biotechnology, School of Biotechnology, Madurai Kamaraj University, Madurai, India
| | - Sukumaran Sunitha
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States
| |
Collapse
|
10
|
Li M, Li C, Jiang K, Li K, Zhang J, Sun M, Wu G, Qing L. Characterization of Pathogenicity-Associated V2 Protein of Tobacco Curly Shoot Virus. Int J Mol Sci 2021; 22:E923. [PMID: 33477652 PMCID: PMC7831499 DOI: 10.3390/ijms22020923] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 11/17/2022] Open
Abstract
V2 proteins encoded by some whitefly-transmitted geminiviruses were reported to be functionally important proteins. However, the functions of the V2 protein of tobacco curly shoot virus (TbCSV), a monopartite begomovirus that causes leaf curl disease on tomato and tobacco in China, remains to be characterized. In our report, an Agrobacterium infiltration-mediated transient expression assay indicated that TbCSV V2 can suppress local and systemic RNA silencing and the deletion analyses demonstrated that the amino acid region 1-92 of V2, including the five predicted α-helices, are required for local RNA silencing suppression. Site-directed substitutions showed that the conserved basic and ring-structured amino acids in TbCSV V2 are critical for its suppressor activity. Potato virus X-mediated heteroexpression of TbCSV V2 in Nicotiana benthamiana induced hypersensitive response-like (HR-like) cell death and systemic necrosis in a manner independent of V2's suppressor activity. Furthermore, TbCSV infectious clone mutant with untranslated V2 protein (TbCSV∆V2) could not induce visual symptoms, and coinfection with betasatellite (TbCSB) could obviously elevate the viral accumulation and symptom development. Interestingly, symptom recovery occurred at 15 days postinoculation (dpi) and onward in TbCSV∆V2/TbCSB-inoculated plants. The presented work contributes to understanding the RNA silencing suppression activity of TbCSV V2 and extends our knowledge of the multifunctional role of begomovirus-encoded V2 proteins during viral infections.
Collapse
Affiliation(s)
- Mingjun Li
- Correspondence: (M.L.); (L.Q.); Tel.: +86-023-68250517 (L.Q.)
| | | | | | | | | | | | | | - Ling Qing
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing 400716, China; (C.L.); (K.J.); (K.L.); (J.Z.); (M.S.); (G.W.)
| |
Collapse
|
11
|
Ramesh SV, Yogindran S, Gnanasekaran P, Chakraborty S, Winter S, Pappu HR. Virus and Viroid-Derived Small RNAs as Modulators of Host Gene Expression: Molecular Insights Into Pathogenesis. Front Microbiol 2021; 11:614231. [PMID: 33584579 PMCID: PMC7874048 DOI: 10.3389/fmicb.2020.614231] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 11/19/2020] [Indexed: 02/01/2023] Open
Abstract
Virus-derived siRNAs (vsiRNAs) generated by the host RNA silencing mechanism are effectors of plant’s defense response and act by targeting the viral RNA and DNA in post-transcriptional gene silencing (PTGS) and transcriptional gene silencing (TGS) pathways, respectively. Contrarily, viral suppressors of RNA silencing (VSRs) compromise the host RNA silencing pathways and also cause disease-associated symptoms. In this backdrop, reports describing the modulation of plant gene(s) expression by vsiRNAs via sequence complementarity between viral small RNAs (sRNAs) and host mRNAs have emerged. In some cases, silencing of host mRNAs by vsiRNAs has been implicated to cause characteristic symptoms of the viral diseases. Similarly, viroid infection results in generation of sRNAs, originating from viroid genomic RNAs, that potentially target host mRNAs causing typical disease-associated symptoms. Pathogen-derived sRNAs have been demonstrated to have the propensity to target wide range of genes including host defense-related genes, genes involved in flowering and reproductive pathways. Recent evidence indicates that vsiRNAs inhibit host RNA silencing to promote viral infection by acting as decoy sRNAs. Nevertheless, it remains unclear if the silencing of host transcripts by viral genome-derived sRNAs are inadvertent effects due to fortuitous pairing between vsiRNA and host mRNA or the result of genuine counter-defense strategy employed by viruses to enhance its survival inside the plant cell. In this review, we analyze the instances of such cross reaction between pathogen-derived vsiRNAs and host mRNAs and discuss the molecular insights regarding the process of pathogenesis.
Collapse
Affiliation(s)
- S V Ramesh
- ICAR-Central Plantation Crops Research Institute, Kasaragod, India
| | - Sneha Yogindran
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Prabu Gnanasekaran
- Department of Plant Pathology, Washington State University, Pullman, WA, United States
| | | | - Stephan Winter
- Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Braunschweig, Germany
| | - Hanu R Pappu
- Department of Plant Pathology, Washington State University, Pullman, WA, United States
| |
Collapse
|
12
|
Zarreen F, Chakraborty S. Epigenetic regulation of geminivirus pathogenesis: a case of relentless recalibration of defence responses in plants. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6890-6906. [PMID: 32869846 DOI: 10.1093/jxb/eraa406] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Geminiviruses constitute one of the largest families of plant viruses and they infect many economically important crops. The proteins encoded by the single-stranded DNA genome of these viruses interact with a wide range of host proteins to cause global dysregulation of cellular processes and help establish infection in the host. Geminiviruses have evolved numerous mechanisms to exploit host epigenetic processes to ensure the replication and survival of the viral genome. Here, we review our current knowledge of diverse epigenetic processes that have been implicated in the regulation of geminivirus pathogenesis, including DNA methylation, histone post-transcriptional modification, chromatin remodelling, and nucleosome repositioning. In addition, we discuss the currently limited evidence of host epigenetic defence responses that are aimed at counteracting geminivirus infection, and the potential for exploiting these responses for the generation of resistance against geminiviruses in crop species.
Collapse
Affiliation(s)
- Fauzia Zarreen
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| |
Collapse
|
13
|
Wang L, Ding Y, He L, Zhang G, Zhu JK, Lozano-Duran R. A virus-encoded protein suppresses methylation of the viral genome through its interaction with AGO4 in the Cajal body. eLife 2020; 9:e55542. [PMID: 33064077 PMCID: PMC7567605 DOI: 10.7554/elife.55542] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 09/23/2020] [Indexed: 12/11/2022] Open
Abstract
In plants, establishment of de novo DNA methylation is regulated by the RNA-directed DNA methylation (RdDM) pathway. RdDM machinery is known to concentrate in the Cajal body, but the biological significance of this localization has remained elusive. Here, we show that the antiviral methylation of the Tomato yellow leaf curl virus (TYLCV) genome requires the Cajal body in Nicotiana benthamiana cells. Methylation of the viral genome is countered by a virus-encoded protein, V2, which interacts with the central RdDM component AGO4, interfering with its binding to the viral DNA; Cajal body localization of the V2-AGO4 interaction is necessary for the viral protein to exert this function. Taken together, our results draw a long sought-after functional connection between RdDM, the Cajal body, and antiviral DNA methylation, paving the way for a deeper understanding of DNA methylation and antiviral defences in plants.
Collapse
Affiliation(s)
- Liping Wang
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesBeijingChina
- University of the Chinese Academy of SciencesBeijingChina
| | - Yi Ding
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesBeijingChina
- University of the Chinese Academy of SciencesBeijingChina
| | - Li He
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesBeijingChina
| | - Guiping Zhang
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesBeijingChina
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesBeijingChina
| | - Rosa Lozano-Duran
- Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of SciencesBeijingChina
| |
Collapse
|
14
|
Beam K, Ascencio-Ibáñez JT. Geminivirus Resistance: A Minireview. FRONTIERS IN PLANT SCIENCE 2020; 11:1131. [PMID: 32849693 PMCID: PMC7396689 DOI: 10.3389/fpls.2020.01131] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 07/10/2020] [Indexed: 05/04/2023]
Abstract
A continuing challenge to crop production worldwide is the spectrum of diseases caused by geminiviruses, a large family of small circular single-stranded DNA viruses. These viruses are quite diverse, some containing mono- or bi-partite genomes, and infecting a multitude of monocot and dicot plants. There are currently many efforts directed at controlling these diseases. While some of the methods include controlling the insect vector using pesticides or genetic insect resistance (Rodríguez-López et al., 2011), this review will focus on the generation of plants that are resistant to geminiviruses themselves. Genetic resistance was traditionally found by surveying the wild relatives of modern crops for resistance loci; this method is still widely used and successful. However, the quick rate of virus evolution demands a rapid turnover of resistance genes. With better information about virus-host interactions, scientists are now able to target early stages of geminivirus infection in the host, preventing symptom development and viral DNA accumulation.
Collapse
|
15
|
Križnik M, Baebler Š, Gruden K. Roles of small RNAs in the establishment of tolerant interaction between plants and viruses. Curr Opin Virol 2020; 42:25-31. [PMID: 32480352 DOI: 10.1016/j.coviro.2020.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 02/06/2023]
Abstract
In a tolerant plant-virus interaction, viral multiplication is sustained without substantial effects on plant growth or reproduction. Such interactions are, in natural environments, frequent and sometimes even beneficial for both interactors. Here we compiled evidence showing that small RNAs modulate plant immune responses and growth, hence adjusting its physiology to enable a tolerant interaction. Importantly, the role of small RNAs in tolerant interactions resembles that required for establishment of a mutualistic symbiosis. Tolerance can become a sustainable strategy for breeding for virus resistance as selection pressure for emergence of more aggressive strains is low. Understanding the processes underlying establishment of tolerance is, therefore, important for the development of future crops.
Collapse
Affiliation(s)
- Maja Križnik
- National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia
| | - Špela Baebler
- National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia
| | - Kristina Gruden
- National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
| |
Collapse
|
16
|
Corrêa RL, Sanz-Carbonell A, Kogej Z, Müller SY, Ambrós S, López-Gomollón S, Gómez G, Baulcombe DC, Elena SF. Viral Fitness Determines the Magnitude of Transcriptomic and Epigenomic Reprograming of Defense Responses in Plants. Mol Biol Evol 2020; 37:1866-1881. [DOI: 10.1093/molbev/msaa091] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Abstract
Although epigenetic factors may influence the expression of defense genes in plants, their role in antiviral responses and the impact of viral adaptation and evolution in shaping these interactions are still poorly explored. We used two isolates of turnip mosaic potyvirus with varying degrees of adaptation to Arabidopsis thaliana to address these issues. One of the isolates was experimentally evolved in the plant and presented increased load and virulence relative to the ancestral isolate. The magnitude of the transcriptomic responses was larger for the evolved isolate and indicated a role of innate immunity systems triggered by molecular patterns and effectors in the infection process. Several transposable elements located in different chromatin contexts and epigenetic-related genes were also affected. Correspondingly, mutant plants having loss or gain of repressive marks were, respectively, more tolerant and susceptible to turnip mosaic potyvirus, with a more efficient response against the ancestral isolate. In wild-type plants, both isolates induced similar levels of cytosine methylation changes, including in and around transposable elements and stress-related genes. Results collectively suggested that apart from RNA silencing and basal immunity systems, DNA methylation and histone modification pathways may also be required for mounting proper antiviral defenses and that the effectiveness of this type of regulation strongly depends on the degree of viral adaptation to the host.
Collapse
Affiliation(s)
- Régis L Corrêa
- Instituto de Biología Integrativa de Sistemas (I2SysBio), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat de València, Paterna, Valencia, Spain
- Department of Genetics, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Alejandro Sanz-Carbonell
- Instituto de Biología Integrativa de Sistemas (I2SysBio), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat de València, Paterna, Valencia, Spain
| | - Zala Kogej
- Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
- Instituto de Biología Integrativa de Sistemas (I2SysBio), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat de València, Paterna, Valencia, Spain
| | - Sebastian Y Müller
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Silvia Ambrós
- Instituto de Biología Integrativa de Sistemas (I2SysBio), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat de València, Paterna, Valencia, Spain
| | - Sara López-Gomollón
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Gustavo Gómez
- Instituto de Biología Integrativa de Sistemas (I2SysBio), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat de València, Paterna, Valencia, Spain
| | - David C Baulcombe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Santiago F Elena
- Instituto de Biología Integrativa de Sistemas (I2SysBio), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat de València, Paterna, Valencia, Spain
- The Santa Fe Institute, Santa Fe, NM
| |
Collapse
|
17
|
Superinfection by PHYVV Alters the Recovery Process in PepGMV-Infected Pepper Plants. Viruses 2020; 12:v12030286. [PMID: 32151060 PMCID: PMC7150747 DOI: 10.3390/v12030286] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/20/2020] [Accepted: 02/25/2020] [Indexed: 01/02/2023] Open
Abstract
Geminiviruses are important plant pathogens that affect crops around the world. In some geminivirus-host interactions, infected plants show recovery, a phenomenon characterized by symptom disappearance in newly emerging leaves. In pepper-Pepper golden mosaic virus (PepGMV) interaction, the host recovery process involves a silencing mechanism that includes both post-transcriptional (PTGS) and transcriptional (TGS) gene silencing pathways. Under field conditions, PepGMV is frequently found in mixed infections with Pepper huasteco yellow vein virus (PHYVV), another bipartite begomovirus. Mixed infected plants generally show a synergetic phenomenon and do not present recovery. Little is known about the molecular mechanism of this interaction. In the present study, we explored the effect of superinfection by PHYVV on a PepGMV-infected pepper plant showing recovery. Superinfection with PHYVV led to (a) the appearance of severe symptoms, (b) an increase of the levels of PepGMV DNA accumulation, (c) a decrease of the relative methylation levels of PepGMV DNA, and (d) an increase of chromatin activation marks present in viral minichromosomes. Finally, using heterologous expression and silencing suppression reporter systems, we found that PHYVV REn presents TGS silencing suppressor activity, whereas similar experiments suggest that Rep might be involved in suppressing PTGS.
Collapse
|
18
|
Gong YN, Tang RQ, Zhang Y, Peng J, Xian O, Zhang ZH, Zhang SB, Zhang DY, Liu H, Luo XW, Liu Y. The NIa-Protease Protein Encoded by the Pepper Mottle Virus Is a Pathogenicity Determinant and Releases DNA Methylation of Nicotiana benthamiana. Front Microbiol 2020; 11:102. [PMID: 32153517 PMCID: PMC7047827 DOI: 10.3389/fmicb.2020.00102] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 01/17/2020] [Indexed: 12/12/2022] Open
Abstract
It is well documented that the canonical function of NIa-protease (NIa-Pro) of the potyviruses is responsible for cleaving the viral polyprotein into functional proteins. Although NIa-Pro is vital for the infection cycle of potyviruses, the function of NIa-Pro in the interaction of the potyvirus host is not clear. In this study, NIa-Pro is ectopically expressed from a potato virus X (PVX) vector and infiltrates Nicotiana benthamiana wild type and 16-TGS. The pathogenicity and inhibition of host transcriptional gene silencing (TGS) are characterized. Ectopic expression of NIa-Pro from a PVX vector resulted in severe mosaic symptoms followed by a hypersensitive-like response in N. benthamiana. Furthermore, PepMoV NIa-Pro was able to reverse established TGS of a green fluorescent protein transgene by reducing methylation of promoter sequences in N. benthamiana and possessed the capacity to interfere with the global methylation of N. benthamiana. Taken together, the results of this study likely suggest that PepMoV NIa-Pro is a pathogenicity determinant and a potent suppressor of host TGS and suggest that NIa-Pro may employ novel mechanisms to suppress host antiviral defenses. To the best of our knowledge, this is the first report of a plant RNA virus modulating host TGS in a novel manner by interfering with the establishment of the methylation step of the plant DNA methylation pathway.
Collapse
Affiliation(s)
- Yi-Nuo Gong
- Longping Branch, Graduate School of Hunan University, Changsha, China
| | - Ru-Qing Tang
- Hunan Academy of Agricultural Sciences, Changsha, China
| | - Yu Zhang
- Longping Branch, Graduate School of Hunan University, Changsha, China
| | - Jing Peng
- Hunan Academy of Agricultural Sciences, Changsha, China
| | - OuYang Xian
- Hunan Academy of Agricultural Sciences, Changsha, China
| | | | - Song-Bai Zhang
- Longping Branch, Graduate School of Hunan University, Changsha, China.,Hunan Academy of Agricultural Sciences, Changsha, China
| | - De-Yong Zhang
- Longping Branch, Graduate School of Hunan University, Changsha, China.,Hunan Academy of Agricultural Sciences, Changsha, China
| | - Hui Liu
- National Agro-Tech Extension and Service Center, Beijing, China
| | - Xiang-Wen Luo
- Hunan Academy of Agricultural Sciences, Changsha, China
| | - Yong Liu
- Longping Branch, Graduate School of Hunan University, Changsha, China.,Hunan Academy of Agricultural Sciences, Changsha, China
| |
Collapse
|
19
|
Xu M, Mazur MJ, Tao X, Kormelink R. Cellular RNA Hubs: Friends and Foes of Plant Viruses. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:40-54. [PMID: 31415225 DOI: 10.1094/mpmi-06-19-0161-fi] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
RNA granules are dynamic cellular foci that are widely spread in eukaryotic cells and play essential roles in cell growth and development, and immune and stress responses. Different types of granules can be distinguished, each with a specific function and playing a role in, for example, RNA transcription, modification, processing, decay, translation, and arrest. By means of communication and exchange of (shared) components, they form a large regulatory network in cells. Viruses have been reported to interact with one or more of these either cytoplasmic or nuclear granules, and act either proviral, to enable and support viral infection and facilitate viral movement, or antiviral, protecting or clearing hosts from viral infection. This review describes an overview and recent progress on cytoplasmic and nuclear RNA granules and their interplay with virus infection, first in animal systems and as a prelude to the status and current developments on plant viruses, which have been less well studied on this thus far.
Collapse
Affiliation(s)
- Min Xu
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Virology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| | - Magdalena J Mazur
- Laboratory of Virology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| | - Xiaorong Tao
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
| | - Richard Kormelink
- Laboratory of Virology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| |
Collapse
|
20
|
Wang C, Wang C, Zou J, Yang Y, Li Z, Zhu S. Epigenetics in the plant-virus interaction. PLANT CELL REPORTS 2019; 38:1031-1038. [PMID: 31065780 DOI: 10.1007/s00299-019-02414-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 04/25/2019] [Indexed: 05/23/2023]
Abstract
Plants have developed diverse molecular mechanisms to resist viruses. RNA silencing plays a dominant role in antiviral defense. Recent studies have correlated plant antiviral silencing to epigenetic modification in genomic DNA and protein by remodeling the expression levels of coding genes. The plant host methylation level is reprogrammed in response to viral challenge. Genomes of some viruses have been implicated in the epigenetic modification via small RNA-mediated transcriptional gene silencing and post-transcriptional gene silencing. These mechanisms can be primed prior to a virus attack through methylation changes for antiviral defense. This review highlights the findings concerning the methylation changes in plant-virus interactions and demonstrates a possible direction to improve the understanding of plant host methylation regulation in response to viral infection.
Collapse
Affiliation(s)
- Chenguang Wang
- College of Plant Protection, China Agricultural University, Beijing, 100083, China
- Chinese Academy of Inspection and Quarantine, Beijing, 100176, China
| | - Chaonan Wang
- College of Plant Protection, China Agricultural University, Beijing, 100083, China
- Chinese Academy of Inspection and Quarantine, Beijing, 100176, China
| | - Jingze Zou
- College of Biological Sciences, China Agricultural University, Beijing, 100083, China
| | - Yunshu Yang
- Beijing Academy of Food Sciences, Beijing, 100162, China
| | - Zhihong Li
- College of Plant Protection, China Agricultural University, Beijing, 100083, China
| | - Shuifang Zhu
- College of Plant Protection, China Agricultural University, Beijing, 100083, China.
- Chinese Academy of Inspection and Quarantine, Beijing, 100176, China.
| |
Collapse
|
21
|
Wang Y, Wu Y, Gong Q, Ismayil A, Yuan Y, Lian B, Jia Q, Han M, Deng H, Hong Y, Hanley-Bowdoin L, Qi Y, Liu Y. Geminiviral V2 Protein Suppresses Transcriptional Gene Silencing through Interaction with AGO4. J Virol 2019; 93:e01675-18. [PMID: 30626668 PMCID: PMC6401443 DOI: 10.1128/jvi.01675-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 12/18/2018] [Indexed: 12/14/2022] Open
Abstract
In plants, RNA-directed DNA methylation (RdDM)-mediated transcriptional gene silencing (TGS) is a natural antiviral defense against geminiviruses. Several geminiviral proteins have been shown to target the enzymes related to the methyl cycle or histone modification; however, it remains largely unknown whether and by which mechanism geminiviruses directly inhibit RdDM-mediated TGS. In this study, we showed that Cotton leaf curl Multan virus (CLCuMuV) V2 directly interacts with Nicotiana benthamiana AGO4 (NbAGO4) and that the L76S mutation in V2 (V2L76S) abolishes such interaction. We further showed that V2, but not V2L76S, can suppresses RdDM and TGS. Silencing of NbAGO4 inhibits TGS, reduces the viral methylation level, and enhances CLCuMuV DNA accumulation. In contrast, the V2L76S substitution mutant attenuates CLCuMuV infection and enhances the viral methylation level. These findings reveal that CLCuMuV V2 contributes to viral infection by interaction with NbAGO4 to suppress RdDM-mediated TGS in plants.IMPORTANCE In plants, the RNA-directed DNA methylation (RdDM) pathway is a natural antiviral defense mechanism against geminiviruses. However, how geminiviruses counter RdDM-mediated defense is largely unknown. Our findings reveal that Cotton leaf curl Multan virus V2 contributes to viral infection by interaction with NbAGO4 to suppress RNA-directed DNA methylation-mediated transcriptional gene silencing in plants. Our work provides the first evidence that a geminiviral protein is able to directly target core RdDM components to counter RdDM-mediated TGS antiviral defense in plants, which extends our current understanding of viral counters to host antiviral defense.
Collapse
Affiliation(s)
- Yunjing Wang
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Yuyao Wu
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Qian Gong
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Asigul Ismayil
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Yuxiang Yuan
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Bi Lian
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Qi Jia
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Meng Han
- MOE Key Laboratory of Bioinformatics and the Center of Biomedical Analysis, School of Life Sciences, Tsinghua University, Beijing, China
| | - Haiteng Deng
- MOE Key Laboratory of Bioinformatics and the Center of Biomedical Analysis, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yiguo Hong
- Research Center for Plant RNA Signaling, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
| | - Linda Hanley-Bowdoin
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Yijun Qi
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, Tsinghua University, Beijing, China
| |
Collapse
|
22
|
RNA Interference: A Natural Immune System of Plants to Counteract Biotic Stressors. Cells 2019; 8:cells8010038. [PMID: 30634662 PMCID: PMC6356646 DOI: 10.3390/cells8010038] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/01/2019] [Accepted: 01/07/2019] [Indexed: 02/06/2023] Open
Abstract
During plant-pathogen interactions, plants have to defend the living transposable elements from pathogens. In response to such elements, plants activate a variety of defense mechanisms to counteract the aggressiveness of biotic stressors. RNA interference (RNAi) is a key biological process in plants to inhibit gene expression both transcriptionally and post-transcriptionally, using three different groups of proteins to resist the virulence of pathogens. However, pathogens trigger an anti-silencing mechanism through the expression of suppressors to block host RNAi. The disruption of the silencing mechanism is a virulence strategy of pathogens to promote infection in the invaded hosts. In this review, we summarize the RNA silencing pathway, anti-silencing suppressors, and counter-defenses of plants to viral, fungal, and bacterial pathogens.
Collapse
|
23
|
Calil IP, Quadros IPS, Araújo TC, Duarte CEM, Gouveia-Mageste BC, Silva JCF, Brustolini OJB, Teixeira RM, Oliveira CN, Milagres RWMM, Martins GS, Chory J, Reis PAB, Machado JPB, Fontes EPB. A WW Domain-Containing Protein Forms Immune Nuclear Bodies against Begomoviruses. MOLECULAR PLANT 2018; 11:1449-1465. [PMID: 30296599 DOI: 10.1016/j.molp.2018.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 08/27/2018] [Accepted: 09/28/2018] [Indexed: 05/23/2023]
Abstract
The bipartite begomoviruses (Geminiviridae family), which are DNA viruses that replicate in the nucleus of infected cells, encode the nuclear shuttle protein (NSP) to facilitate the translocation of viral DNA from the nucleus to the cytoplasm via nuclear pores. This intracellular trafficking of NSP-DNA complexes is accessorized by the NSP-interacting guanosine triphosphatase (NIG) at the cytosolic side. Here, we report the nuclear redistribution of NIG by AtWWP1, a WW domain-containing protein that forms immune nuclear bodies (NBs) against begomoviruses. We demonstrated that AtWWP1 relocates NIG from the cytoplasm to the nucleus where it is confined to AtWWP1-NBs, suggesting that the NIG-AtWWP1 interaction may interfere with the NIG pro-viral function associated with its cytosolic localization. Consistent with this assumption, loss of AtWWP1 function cuased plants more susceptible to begomovirus infection, whereas overexpression of AtWWP1 enhanced plant resistance to begomovirus. Furthermore, we found that a mutant version of AtWWP1 defective for NB formation was no longer capable of interacting with and relocating NIG to the nucleus and lost its immune function against begomovirus. The antiviral function of AtWWP1-NBs, however, could be antagonized by viral infection that induced either the disruption or a decrease in the number of AtWWP1-NBs. Collectively, these results led us to propose that AtWWP1 organizes nuclear structures into nuclear foci, which provide intrinsic immunity against begomovirus infection.
Collapse
Affiliation(s)
- Iara P Calil
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Iana P S Quadros
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Thais C Araújo
- National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Christiane E M Duarte
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Bianca C Gouveia-Mageste
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - José Cleydson F Silva
- National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Otávio J B Brustolini
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Ruan M Teixeira
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Cauê N Oliveira
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Rafael W M M Milagres
- National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Gilberto S Martins
- National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; Departament of Genetics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Joanne Chory
- Howard Hughes Medical Institute and Plant Biology Laboratory, The Salk Institute of Biological Studies, La Jolla, CA 92037, USA
| | - Pedro A B Reis
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil
| | - Joao Paulo B Machado
- National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; Agronomy Institute, Universidade Federal de Viçosa, Campus Florestal, Florestal, Minas Gerais 35690-000, Brazil.
| | - Elizabeth P B Fontes
- Departament of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil; National Institute of Science and Technology in Plant-Pest Interactions, Bioagro, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-000, Brazil.
| |
Collapse
|
24
|
Pooggin MM. Small RNA-Omics for Plant Virus Identification, Virome Reconstruction, and Antiviral Defense Characterization. Front Microbiol 2018; 9:2779. [PMID: 30524398 PMCID: PMC6256188 DOI: 10.3389/fmicb.2018.02779] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 10/30/2018] [Indexed: 11/13/2022] Open
Abstract
RNA interference (RNAi)-based antiviral defense generates small interfering RNAs that represent the entire genome sequences of both RNA and DNA viruses as well as viroids and viral satellites. Therefore, deep sequencing and bioinformatics analysis of small RNA population (small RNA-ome) allows not only for universal virus detection and genome reconstruction but also for complete virome reconstruction in mixed infections. Viral infections (like other stress factors) can also perturb the RNAi and gene silencing pathways regulating endogenous gene expression and repressing transposons and host genome-integrated endogenous viral elements which can potentially be released from the genome and contribute to disease. This review describes the application of small RNA-omics for virus detection, virome reconstruction and antiviral defense characterization in cultivated and non-cultivated plants. Reviewing available evidence from a large and ever growing number of studies of naturally or experimentally infected hosts revealed that all families of land plant viruses, their satellites and viroids spawn characteristic small RNAs which can be assembled into contigs of sufficient length for virus, satellite or viroid identification and for exhaustive reconstruction of complex viromes. Moreover, the small RNA size, polarity and hotspot profiles reflect virome interactions with the plant RNAi machinery and allow to distinguish between silent endogenous viral elements and their replicating episomal counterparts. Models for the biogenesis and functions of small interfering RNAs derived from all types of RNA and DNA viruses, satellites and viroids as well as endogenous viral elements are presented and discussed.
Collapse
Affiliation(s)
- Mikhail M. Pooggin
- Institut National de la Recherche Agronomique, UMR BGPI, Montpellier, France
| |
Collapse
|
25
|
Bennett A, Rodriguez D, Lister S, Boulton M, McKenna R, Agbandje-McKenna M. Assembly and disassembly intermediates of maize streak geminivirus. Virology 2018; 525:224-236. [PMID: 30300759 DOI: 10.1016/j.virol.2018.09.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 09/16/2018] [Accepted: 09/16/2018] [Indexed: 11/17/2022]
Abstract
Maize streak virus (MSV) belongs to the Geminiviridae. Four forms of MSV coat protein (CP) assemblages were isolated from infected plants: geminate capsids, T = 1 icosahedral capsids, pentamers and decamers of CPs. Sequential exposure of geminate capsids to increasing pH, from 4.8 to 7.2 was used to monitor capsid disassembly. The capsids remain intact at pH4.8, disassemble to decamers and pentamers by pH6.4 and aggregate by pH7.2. Similarly, high salt and divalent cations cause disassembly. The disassembly process was reversed in low pH and low salt, but resulted in empty (no DNA) single and geminate capsid assemblies. This is likely due to disruption of CP-DNA interactions under acidic conditions and suggests a mechanism of capsid assembly in which the genome is packaged into preformed empty capsids. The pH assay developed in this study provides a method for characterizing the conditions that are the determinants of geminivirus assembly and disassembly.
Collapse
Affiliation(s)
- Antonette Bennett
- Department of Biochemistry and Molecular Biology, College of Medicine, Center for Structural Biology, McKnight Brain Institute, University of Florida, Gainesville, FL 32610-0245, United States
| | - David Rodriguez
- Department of Biochemistry and Molecular Biology, College of Medicine, Center for Structural Biology, McKnight Brain Institute, University of Florida, Gainesville, FL 32610-0245, United States
| | - Samantha Lister
- John Innes Center, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK
| | - Margaret Boulton
- John Innes Center, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, College of Medicine, Center for Structural Biology, McKnight Brain Institute, University of Florida, Gainesville, FL 32610-0245, United States
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, College of Medicine, Center for Structural Biology, McKnight Brain Institute, University of Florida, Gainesville, FL 32610-0245, United States.
| |
Collapse
|
26
|
Coursey T, Milutinovic M, Regedanz E, Brkljacic J, Bisaro DM. Arabidopsis Histone Reader EMSY-LIKE 1 Binds H3K36 and Suppresses Geminivirus Infection. J Virol 2018. [PMID: 29875242 DOI: 10.1128/jvi.00219-218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
Abstract
Histone posttranslational modifications (PTMs) impart information that regulates chromatin structure and activity. Their effects are mediated by histone reader proteins that bind specific PTMs to modify chromatin and/or recruit appropriate effectors to alter the chromatin landscape. Despite their crucial juxtaposition between information and functional outcome, relatively few plant histone readers have been identified, and nothing is known about their impact on viral chromatin and pathogenesis. We used the geminivirus Cabbage leaf curl virus (CaLCuV) as a model to functionally characterize two recently identified reader proteins, EMSY-LIKE 1 (EML1) and EML3, which contain Tudor-like Agenet domains predictive of histone PTM binding function. Here, we show that mutant Arabidopsis plants exhibit contrasting hypersusceptible (eml1) and tolerant (eml3) responses to CaLCuV infection and that EML1 deficiency correlates with RNA polymerase II (Pol II) enrichment on viral chromatin and upregulated viral gene expression. Consistent with reader activity, EML1 and EML3 associate with nucleosomes and with CaLCuV chromatin, suggesting a direct impact on pathogenesis. We also demonstrate that EML1 and EML3 bind peptides containing histone H3 lysine 36 (H3K36), a PTM usually associated with active gene expression. The interaction encompasses multiple H3K36 PTMs, including methylation and acetylation, suggesting nuanced regulation. Furthermore, EML1 and EML3 associate with similar regions of viral chromatin, implying possible competition between the two readers. Regions of EML1 and EML3 association correlate with sites of trimethylated H3K36 (H3K36me3) enrichment, consistent with regulation of geminivirus chromatin by direct EML targeting.IMPORTANCE Histone PTMs convey information that regulates chromatin compaction and DNA accessibility. Histone reader proteins bind specific PTMs and translate their effects by modifying chromatin and/or by recruiting effectors that alter chromatin structure or activity. In this study, CaLCuV was used to characterize the activities of two Arabidopsis Agenet domain histone readers, EML1 and EML3. We show that eml1 mutants are hypersusceptible to CaLCuV, whereas eml3 plants are more tolerant of infection than wild-type plants. We also demonstrate that EML1 and EML3 associate with histones and viral chromatin in planta and that both proteins bind peptides containing H3K36, a PTM associated with active gene expression. Consistent with antiviral activity, EML1 suppresses CaLCuV gene expression and reduces Pol II access to viral chromatin. By linking EML1 and EML3 to pathogenesis, these studies have expanded our knowledge of histone reader proteins and uncovered an additional level of viral chromatin regulation.
Collapse
Affiliation(s)
- Tami Coursey
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio, USA
- Center for Applied Plant Sciences, The Ohio State University, Columbus, Ohio, USA
- Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
- Infectious Diseases Institute, The Ohio State University, Columbus, Ohio, USA
- Graduate Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, Ohio, USA
| | - Milica Milutinovic
- Center for Applied Plant Sciences, The Ohio State University, Columbus, Ohio, USA
- Institute for Biological Research Siniša Stanković, University of Belgrade, Belgrade, Serbia
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, Ohio, USA
| | - Elizabeth Regedanz
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio, USA
- Center for Applied Plant Sciences, The Ohio State University, Columbus, Ohio, USA
- Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
- Infectious Diseases Institute, The Ohio State University, Columbus, Ohio, USA
| | - Jelena Brkljacic
- Center for Applied Plant Sciences, The Ohio State University, Columbus, Ohio, USA
- Arabidopsis Biological Resource Center, The Ohio State University, Columbus, Ohio, USA
| | - David M Bisaro
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio, USA
- Center for Applied Plant Sciences, The Ohio State University, Columbus, Ohio, USA
- Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA
- Infectious Diseases Institute, The Ohio State University, Columbus, Ohio, USA
- Graduate Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, Ohio, USA
| |
Collapse
|
27
|
Arabidopsis Histone Reader EMSY-LIKE 1 Binds H3K36 and Suppresses Geminivirus Infection. J Virol 2018; 92:JVI.00219-18. [PMID: 29875242 DOI: 10.1128/jvi.00219-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 05/27/2018] [Indexed: 11/20/2022] Open
Abstract
Histone posttranslational modifications (PTMs) impart information that regulates chromatin structure and activity. Their effects are mediated by histone reader proteins that bind specific PTMs to modify chromatin and/or recruit appropriate effectors to alter the chromatin landscape. Despite their crucial juxtaposition between information and functional outcome, relatively few plant histone readers have been identified, and nothing is known about their impact on viral chromatin and pathogenesis. We used the geminivirus Cabbage leaf curl virus (CaLCuV) as a model to functionally characterize two recently identified reader proteins, EMSY-LIKE 1 (EML1) and EML3, which contain Tudor-like Agenet domains predictive of histone PTM binding function. Here, we show that mutant Arabidopsis plants exhibit contrasting hypersusceptible (eml1) and tolerant (eml3) responses to CaLCuV infection and that EML1 deficiency correlates with RNA polymerase II (Pol II) enrichment on viral chromatin and upregulated viral gene expression. Consistent with reader activity, EML1 and EML3 associate with nucleosomes and with CaLCuV chromatin, suggesting a direct impact on pathogenesis. We also demonstrate that EML1 and EML3 bind peptides containing histone H3 lysine 36 (H3K36), a PTM usually associated with active gene expression. The interaction encompasses multiple H3K36 PTMs, including methylation and acetylation, suggesting nuanced regulation. Furthermore, EML1 and EML3 associate with similar regions of viral chromatin, implying possible competition between the two readers. Regions of EML1 and EML3 association correlate with sites of trimethylated H3K36 (H3K36me3) enrichment, consistent with regulation of geminivirus chromatin by direct EML targeting.IMPORTANCE Histone PTMs convey information that regulates chromatin compaction and DNA accessibility. Histone reader proteins bind specific PTMs and translate their effects by modifying chromatin and/or by recruiting effectors that alter chromatin structure or activity. In this study, CaLCuV was used to characterize the activities of two Arabidopsis Agenet domain histone readers, EML1 and EML3. We show that eml1 mutants are hypersusceptible to CaLCuV, whereas eml3 plants are more tolerant of infection than wild-type plants. We also demonstrate that EML1 and EML3 associate with histones and viral chromatin in planta and that both proteins bind peptides containing H3K36, a PTM associated with active gene expression. Consistent with antiviral activity, EML1 suppresses CaLCuV gene expression and reduces Pol II access to viral chromatin. By linking EML1 and EML3 to pathogenesis, these studies have expanded our knowledge of histone reader proteins and uncovered an additional level of viral chromatin regulation.
Collapse
|