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Kong X, Yang M, Le BH, He W, Hou Y. The master role of siRNAs in plant immunity. MOLECULAR PLANT PATHOLOGY 2022; 23:1565-1574. [PMID: 35869407 PMCID: PMC9452763 DOI: 10.1111/mpp.13250] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 06/18/2022] [Accepted: 06/21/2022] [Indexed: 06/01/2023]
Abstract
Gene silencing mediated by small noncoding RNAs (sRNAs) is a fundamental gene regulation mechanism in eukaryotes that broadly governs cellular processes. It has been established that sRNAs are critical regulators of plant growth, development, and antiviral defence, while accumulating studies support positive roles of sRNAs in plant defence against bacteria and eukaryotic pathogens such as fungi and oomycetes. Emerging evidence suggests that plant sRNAs move between species and function as antimicrobial agents against nonviral parasites. Multiple plant pathosystems have been shown to involve a similar exchange of small RNAs between species. Recent analysis about extracellular sRNAs shed light on the understanding of the selection and transportation of sRNAs moving from plant to parasites. In this review, we summarize current advances regarding the function and regulatory mechanism of plant endogenous small interfering RNAs (siRNAs) in mediating plant defence against pathogen intruders including viruses, bacteria, fungi, oomycetes, and parasitic plants. Beyond that, we propose potential mechanisms behind the sorting of sRNAs moving between species and the idea that engineering siRNA-producing loci could be a useful strategy to improve disease resistance of crops.
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Affiliation(s)
- Xiuzhen Kong
- Shanghai Collaborative Innovation Center of Agri‐Seeds/School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Meng Yang
- Shanghai Collaborative Innovation Center of Agri‐Seeds/School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
| | - Brandon H. Le
- Department of Botany and Plant Sciences, Institute of Integrative Genome BiologyUniversity of CaliforniaRiversideCaliforniaUSA
| | - Wenrong He
- Plant Molecular and Cellular Biology LaboratorySalk Institute for Biological StudiesLa JollaCaliforniaUSA
| | - Yingnan Hou
- Shanghai Collaborative Innovation Center of Agri‐Seeds/School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina
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Komatsu K, Hammond J. Plantago asiatica mosaic virus: An emerging plant virus causing necrosis in lilies and a new model RNA virus for molecular research. MOLECULAR PLANT PATHOLOGY 2022; 23:1401-1414. [PMID: 35856603 PMCID: PMC9452766 DOI: 10.1111/mpp.13243] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 06/08/2022] [Accepted: 06/10/2022] [Indexed: 06/01/2023]
Abstract
TAXONOMY Plantago asiatica mosaic virus belongs to the genus Potexvirus in the family Alphaflexiviridae of the order Tymovirales. VIRION AND GENOME PROPERTIES Plantago asiatica mosaic virus (PlAMV) has flexuous virions of approximately 490-530 nm in length and 10-15 nm in width. The genome of PlAMV consists of a single-stranded, positive-sense RNA of approximately 6.13 kb. It contains five open reading frames (ORFs 1-5), encoding a putative viral polymerase (RdRp), movement proteins (triple gene block proteins, TGBp1-3), and coat protein (CP), respectively. HOST RANGE PlAMV has an exceptionally wide host range and has been isolated from various wild plants, including Plantago asiatica, Nandina domestica, Rehmannia glutinosa, and other weed plants. Experimentally PlAMV can infect many plant species including Nicotiana benthamiana and Arabidopsis thaliana. It also infects ornamental lilies and frequently causes severe necrotic symptoms. However, host range varies depending on isolates, which show significant biological diversity within the species. GENOME DIVERSITY PlAMV can be separated into five clades based on phylogenetic analyses; nucleotide identities are significantly low between isolates in the different clades. TRANSMISSION PlAMV is not reported to be transmitted by biological vectors. Virions of PlAMV are quite stable and it can be transmitted efficiently by mechanical contact. DISEASE SYMPTOMS PlAMV causes red-rusted systemic necrosis in ornamental lilies, but it shows much weaker, if any, symptoms in wild plants such as P. asiatica. CONTROL Control of the disease caused by PlAMV is based mainly on rapid diagnosis and elimination of the infected bulbs or plants.
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Affiliation(s)
- Ken Komatsu
- Graduate School of AgricultureTokyo University of Agriculture and Technology (TUAT)FuchuJapan
| | - John Hammond
- US Department of AgricultureAgricultural Research Service (USDA‐ARS)BeltsvilleMarylandUSA
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Abstract
Adaptive antiviral immunity in plants is an RNA-based mechanism in which small RNAs derived from both strands of the viral RNA are guides for an Argonaute (AGO) nuclease. The primed AGO specifically targets and silences the viral RNA. In plants this system has diversified to involve mobile small interfering RNAs (siRNAs), an amplification system involving secondary siRNAs and targeting mechanisms involving DNA methylation. Most, if not all, plant viruses encode multifunctional proteins that are suppressors of RNA silencing that may also influence the innate immune system and fine-tune the virus-host interaction. Animal viruses similarly trigger RNA silencing, although it may be masked in differentiated cells by the interferon system and by the action of the virus-encoded suppressor proteins. There is huge potential for RNA silencing to combat viral disease in crops, farm animals, and people, although there are complications associated with the various strategies for siRNA delivery including transgenesis. Alternative approaches could include using breeding or small molecule treatment to enhance the inherent antiviral capacity of infected cells.
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Affiliation(s)
- David C Baulcombe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom;
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Samarfard S, Ghorbani A, Karbanowicz TP, Lim ZX, Saedi M, Fariborzi N, McTaggart AR, Izadpanah K. Regulatory non-coding RNA: The core defense mechanism against plant pathogens. J Biotechnol 2022; 359:82-94. [PMID: 36174794 DOI: 10.1016/j.jbiotec.2022.09.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 09/18/2022] [Accepted: 09/21/2022] [Indexed: 12/13/2022]
Abstract
Plant pathogens damage crops and threaten global food security. Plants have evolved complex defense networks against pathogens, using crosstalk among various signaling pathways. Key regulators conferring plant immunity through signaling pathways include protein-coding genes and non-coding RNAs (ncRNAs). The discovery of ncRNAs in plant transcriptomes was first considered "transcriptional noise". Recent reviews have highlighted the importance of non-coding RNAs. However, understanding interactions among different types of noncoding RNAs requires additional research. This review attempts to consider how long-ncRNAs, small-ncRNAs and circular RNAs interact in response to pathogenic diseases within different plant species. Developments within genomics and bioinformatics could lead to the further discovery of plant ncRNAs, knowledge of their biological roles, as well as an understanding of their importance in exploiting the recent molecular-based technologies for crop protection.
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Affiliation(s)
- Samira Samarfard
- Department of Primary Industries and Regional Development, DPIRD Diagnostic Laboratory Services, South Perth, WA, Australia
| | - Abozar Ghorbani
- Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute (NSTRI), Karaj, the Islamic Republic of Iran.
| | | | - Zhi Xian Lim
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Mahshid Saedi
- Department of Plant Protection, Faculty of Agriculture, University of Kurdistan, Sanandaj, the Islamic Republic of Iran
| | - Niloofar Fariborzi
- Department of Medical Entomology and Vector Control, School of Health, Shiraz University of Medical Sciences, Shiraz, the Islamic Republic of Iran
| | - Alistair R McTaggart
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Ecosciences Precinct, Dutton Park, QLD 4102, Australia
| | - Keramatollah Izadpanah
- Plant Virology Research Center, College of Agriculture, Shiraz University, Shiraz, the Islamic Republic of Iran
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55
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Yadav V. Computational evidence based perspective on the plausible repositioning of fluoroquinolones for COVID-19 treatment. Curr Comput Aided Drug Des 2022; 18:CAD-EPUB-126248. [PMID: 36093826 DOI: 10.2174/1573409918666220909094645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 06/13/2022] [Accepted: 07/22/2022] [Indexed: 11/22/2022]
Abstract
The coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has become a serious global healthcare crisis, so there is an emergence of identifying efficacious therapeutic options. In a setting where there is an unavailability of definitive medication along with the constant eruption of vaccine-related controversies, the drug-repositioning approach seems to be an ideal step for the management of COVID-19 patients. Fluoroquinolones (FQs) are commonly prescribed antibiotics for the treatment of genitourinary tract and upper respiratory tract infections, including severe community-acquired pneumonia. Research over the years has postulated multifaceted implications of FQs in various pathological conditions. Previously, it has been reported that few, but not all FQs, possess strong antiviral activity with an unknown mechanism of action. Herein, an interesting perspective is discussed on repositioning possibilities of FQs for the SARS-CoV-2 infections based on the recent in silico evidential support. Noteworthy, FQs possess immunomodulatory and bactericidal activity which could be valuable for patients dealing with COVID-19 related complications. Conclusively, the current perspective could pave the way to initiate pre-clinical testing of FQs against several strains of SARS-CoV-2.
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Affiliation(s)
- Vikas Yadav
- Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège, Sart-Tilman, 4000, Liège, Belgium
- Department of Translational Medicine, Skane University Hospital, Clinical Research Centre, Lund University, Malmö, Sweden
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Kravchik M, Shnaider Y, Abebie B, Shtarkman M, Kumari R, Kumar S, Leibman D, Spiegelman Z, Gal‐On A. Knockout of SlTOM1 and SlTOM3 results in differential resistance to tobamovirus in tomato. MOLECULAR PLANT PATHOLOGY 2022; 23:1278-1289. [PMID: 35706371 PMCID: PMC9366062 DOI: 10.1111/mpp.13227] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 04/13/2022] [Accepted: 04/13/2022] [Indexed: 05/15/2023]
Abstract
During tobamovirus-host coevolution, tobamoviruses developed numerous interactions with host susceptibility factors and exploited these interactions for replication and movement. The plant-encoded TOBAMOVIRUS MULTIPLICATION (TOM) susceptibility proteins interact with the tobamovirus replicase proteins and allow the formation of the viral replication complex. Here CRISPR/Cas9-mediated mutagenesis allowed the exploration of the roles of SlTOM1a, SlTOM1b, and SlTOM3 in systemic tobamovirus infection of tomato. Knockouts of both SlTOM1a and SlTOM3 in sltom1a/sltom3 plants resulted in an asymptomatic response to the infection with recently emerged tomato brown rugose fruit virus (ToBRFV). In addition, an accumulation of ToBRFV RNA and coat protein (CP) in sltom1a/sltom3 mutant plants was 516- and 25-fold lower, respectively, than in wild-type (WT) plants at 12 days postinoculation. In marked contrast, sltom1a/sltom3 plants were susceptible to previously known tomato viruses, tobacco mosaic virus (TMV) and tomato mosaic virus (ToMV), indicating that SlTOM1a and SlTOM3 are not essential for systemic infection of TMV and ToMV in tomato plants. Knockout of SlTOM1b alone did not contribute to ToBRFV and ToMV resistance. However, in triple mutants sltom1a/sltom3/sltom1b, ToMV accumulation was three-fold lower than in WT plants, with no reduction in symptoms. These results indicate that SlTOM1a and SlTOM3 are essential for the replication of ToBRFV, but not for ToMV and TMV, which are associated with additional susceptibility proteins. Additionally, we showed that SlTOM1a and SlTOM3 positively regulate the tobamovirus susceptibility gene SlARL8a3. Moreover, we found that the SlTOM family is involved in the regulation of plant development.
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Affiliation(s)
- Michael Kravchik
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Yulia Shnaider
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Bekele Abebie
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Meital Shtarkman
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Reenu Kumari
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Surender Kumar
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Diana Leibman
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Ziv Spiegelman
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
| | - Amit Gal‐On
- Department of Plant Pathology and Weed ResearchAgricultural Research OrganizationRishon LeTsiyonIsrael
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Shang K, Xu Y, Cao W, Xie X, Zhang Y, Zhang J, Liu H, Zhou S, Zhu X, Zhu C. Potato (Solanum tuberosum L.) non-specific lipid transfer protein StLTP6 promotes viral infection by inhibiting virus-induced RNA silencing. PLANTA 2022; 256:54. [PMID: 35927530 DOI: 10.1007/s00425-022-03948-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
For the first time it is reported that members of the nsLTP protein family could promote viral infection by inhibiting virus-induced RNA silencing. Non-specific lipid transfer proteins (nsLTPs) are a class of soluble proteins with low relative molecular weight and widely present in higher plants. The role of nsLTPs in biotic and abiotic stresses has been studied, but no report has shown that nsLTPs play a role in the process of viral infection. We report the function and mechanism of the classical nsLTP protein StLTP6 in viral infection. We found that StLTP6 expression was remarkably upregulated in potato infected with potato virus Y and potato virus S. The infection efficiency and virus content of StLTP6-overexpressed potato and Nicotiana benthamiana were remarkable increased. Further study found that the overexpression of StLTP6 inhibited the expression of multiple genes in the RNA silencing pathway, thereby inhibiting virus-induced RNA silencing. This result indicated that StLTP6 expression was induced during viral infection to inhibit the resistance of virus-induced RNA silencing and promote viral infection. In summary, we reported the role of StLTP6 in viral infection, broadening the biological function range of the nsLTP family and providing valuable information for the study of viral infection mechanism.
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Affiliation(s)
- Kaijie Shang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
- College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Yang Xu
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, 266100, China
| | - Weilin Cao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Xiaoying Xie
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Yanru Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Jingfeng Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Hongmei Liu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Shumei Zhou
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Xiaoping Zhu
- College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
| | - Changxiang Zhu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
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Hoffmann G, Mahboubi A, Bente H, Garcia D, Hanson J, Hafrén A. Arabidopsis RNA processing body components LSM1 and DCP5 aid in the evasion of translational repression during Cauliflower mosaic virus infection. THE PLANT CELL 2022; 34:3128-3147. [PMID: 35511183 PMCID: PMC9338796 DOI: 10.1093/plcell/koac132] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/24/2022] [Indexed: 06/14/2023]
Abstract
Viral infections impose extraordinary RNA stress, triggering cellular RNA surveillance pathways such as RNA decapping, nonsense-mediated decay, and RNA silencing. Viruses need to maneuver among these pathways to establish infection and succeed in producing high amounts of viral proteins. Processing bodies (PBs) are integral to RNA triage in eukaryotic cells, with several distinct RNA quality control pathways converging for selective RNA regulation. In this study, we investigated the role of Arabidopsis thaliana PBs during Cauliflower mosaic virus (CaMV) infection. We found that several PB components are co-opted into viral factories that support virus multiplication. This pro-viral role was not associated with RNA decay pathways but instead, we established that PB components are helpers in viral RNA translation. While CaMV is normally resilient to RNA silencing, dysfunctions in PB components expose the virus to this pathway, which is similar to previous observations for transgenes. Transgenes, however, undergo RNA quality control-dependent RNA degradation and transcriptional silencing, whereas CaMV RNA remains stable but becomes translationally repressed through decreased ribosome association, revealing a unique dependence among PBs, RNA silencing, and translational repression. Together, our study shows that PB components are co-opted by the virus to maintain efficient translation, a mechanism not associated with canonical PB functions.
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Affiliation(s)
- Gesa Hoffmann
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala 75007, Sweden
- Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Amir Mahboubi
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, Umeå, Sweden
| | - Heinrich Bente
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences, Uppsala 75007, Sweden
- Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Damien Garcia
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France
| | - Johannes Hanson
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, Umeå, Sweden
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Pérez-Cañamás M, Taliansky M, Hernández C. A Viral Suppressor of RNA Silencing May Be Targeting a Plant Defence Pathway Involving Fibrillarin. PLANTS 2022; 11:plants11151903. [PMID: 35893605 PMCID: PMC9331457 DOI: 10.3390/plants11151903] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 11/16/2022]
Abstract
To establish productive infections, viruses must be able both to subdue the host metabolism for their own benefit and to counteract host defences. This frequently results in the establishment of viral–host protein–protein interactions that may have either proviral or antiviral functions. The study of such interactions is essential for understanding the virus–host interplay. Plant viruses with RNA genomes are typically translated, replicated, and encapsidated in the cytoplasm of infected cells. Despite this, a significant array of their encoded proteins has been reported to enter the nucleus, often showing high accumulation at subnuclear structures such as the nucleolus and/or Cajal bodies. However, the biological significance of such a distribution pattern is frequently unknown. Here, we explored whether the nucleolar/Cajal body localization of protein p37 of Pelargonium line pattern virus (PLPV, genus Pelarspovirus, family Tombusviridae), might be related to potential interactions with the nucleolar/Cajal body marker proteins, fibrillarin and coilin. The results revealed that p37, which has a dual role as coat protein and as suppressor of RNA silencing, a major antiviral system in plants, is able to associate with these cellular factors. Analysis of (wildtype and/or mutant) PLPV accumulation in plants with up- or downregulated levels of fibrillarin or coilin have suggested that the former might be involved in an as yet unknown antiviral pathway, which may be targeted by p37. The results suggest that the growing number of functions uncovered for fibrillarin can be wider and may prompt future investigations to unveil the plant antiviral responses in which this key nucleolar component may take part.
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Affiliation(s)
- Miryam Pérez-Cañamás
- Instituto de Biología Molecular y Celular de Plantas (Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia), Ciudad Politécnica de la Innovación, Calle Ingeniero Fausto Elio, Ed. 8E. Camino de Vera s/n, 46022 Valencia, Spain;
| | - Michael Taliansky
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK;
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia
| | - Carmen Hernández
- Instituto de Biología Molecular y Celular de Plantas (Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia), Ciudad Politécnica de la Innovación, Calle Ingeniero Fausto Elio, Ed. 8E. Camino de Vera s/n, 46022 Valencia, Spain;
- Correspondence:
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60
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Kumar K, Mandal SN, Neelam K, de los Reyes BG. MicroRNA-mediated host defense mechanisms against pathogens and herbivores in rice: balancing gains from genetic resistance with trade-offs to productivity potential. BMC PLANT BIOLOGY 2022; 22:351. [PMID: 35850632 PMCID: PMC9290239 DOI: 10.1186/s12870-022-03723-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 06/29/2022] [Indexed: 05/08/2023]
Abstract
BACKGROUND Rice (Oryza sativa L.) is the major source of daily caloric intake for more than 30% of the human population. However, the sustained productivity of this staple food crop is continuously threatened by various pathogens and herbivores. Breeding has been successful in utilizing various mechanisms of defense by gene pyramiding in elite cultivars, but the continuous resurgence of highly resistant races of pathogens and herbivores often overcomes the inherent capacity of host plant immunity. MicroRNAs (miRNAs) are endogenous, short, single-stranded, non-coding RNA molecules that regulate gene expression by sequence-specific cleavage of target mRNA or suppressing target mRNA translation. While miRNAs function as upstream regulators of plant growth, development, and host immunity, their direct effects on growth and development in the context of balancing defenses with agronomic potential have not been extensively discussed and explored as a more viable strategy in breeding for disease and pest resistant cultivars of rice with optimal agronomic potentials. RESULTS Using the available knowledge in rice and other model plants, this review examines the important roles of miRNAs in regulating host responses to various fungal, bacterial, and viral pathogens, and insect pests, in the context of gains and trade-offs to crop yield. Gains from R-gene-mediated resistance deployed in modern rice cultivars are often undermined by the rapid breakdown of resistance, negative pleiotropic effects, and linkage drags with undesirable traits. In stark contrast, several classes of miRNAs are known to efficiently balance the positive gains from host immunity without significant costs in terms of losses in agronomic potentials (i.e., yield penalty) in rice. Defense-related miRNAs such as Osa-miR156, Osa-miR159, Osa-miR162, Osa-miR396, Osa-530, Osa-miR1432, Osa-miR1871, and Osa-miR1873 are critical in fine-tuning and integrating immune responses with physiological processes that are necessary to the maintenance of grain yield. Recent research has shown that many defense-related miRNAs regulate complex and agronomically important traits. CONCLUSIONS Identification of novel immune-responsive miRNAs that orchestrate physiological processes critical to the full expression of agronomic potential will facilitate the stacking of optimal combinations of miRNA-encoding genes to develop high-yielding cultivars with durable resistance to disease and insect pests with minimal penalties to yield.
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Affiliation(s)
- Kishor Kumar
- Faculty Centre for Integrated Rural Development and Management, Ramakrishna Mission Vivekananda Educational and Research Institute, Narendrapur, Kolkata, 700103 India
| | - Swarupa Nanda Mandal
- Department of Plant and Soil Science, Texas Tech University, Lubbock, TX-79415 USA
- Department of Genetics and Plant Breeding, Bidhan Chandra Krishi Viswavidyalaya, Extended Campus, Burdwan, West Bengal 713101 India
| | - Kumari Neelam
- School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, Punjab 141004 India
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61
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Poignavent V, Hoh F, Terral G, Yang Y, Gillet FX, Kim JH, Allemand F, Lacombe E, Brugidou C, Cianferani S, Déméné H, Vignols F. A flexible and original architecture of two unrelated zinc fingers underlies the role of the multitask P1 in RYMV spread. J Mol Biol 2022; 434:167715. [DOI: 10.1016/j.jmb.2022.167715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/28/2022] [Accepted: 06/28/2022] [Indexed: 10/17/2022]
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Ke YD, Huang YW, Viswanath KK, Hu CC, Yeh CM, Mitsuda N, Lin NS, Hsu YH. NbNAC42 and NbZFP3 Transcription Factors Regulate the Virus Inducible NbAGO5 Promoter in Nicotiana benthamiana. FRONTIERS IN PLANT SCIENCE 2022; 13:924482. [PMID: 35812928 PMCID: PMC9261433 DOI: 10.3389/fpls.2022.924482] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/23/2022] [Indexed: 05/27/2023]
Abstract
Plant argonautes (AGOs) play important roles in the defense responses against viruses. The expression of Nicotiana benthamiana AGO5 gene (NbAGO5) is highly induced by Bamboo mosaic virus (BaMV) infection; however, the underlying mechanisms remain elusive. In this study, we have analyzed the potential promoter activities of NbAGO5 and its interactions with viral proteins by using a 2,000 bp fragment, designated as PN1, upstream to the translation initiation of NbAGO5. PN1 and seven serial 5'-deletion mutants (PN2-PN8) were fused with a β-glucuronidase (GUS) reporter and introduced into the N. benthamiana genome by Agrobacterium-mediated transformation for further characterization. It was found that PN4-GUS transgenic plants were able to drive strong GUS expression in the whole plant. In the virus infection tests, the GUS activity was strongly induced in PN4-GUS transgenic plants after being challenged with potexviruses. Infiltration of the transgenic plants individually with BaMV coat protein (CP) or triple gene block protein 1 (TGBp1) revealed that only TGBp1 was crucial for inducing the NbAGO5 promoter. To identify the factors responsible for controlling the activity of the NbAGO5 promoter, we employed yeast one-hybrid screening on a transcription factor cDNA library. The result showed that NbNAC42 and NbZFP3 could directly bind the 704 bp promoter regions of NbAGO5. By using overexpressing and virus-induced gene silencing techniques, we found that NbNAC42 and NbZFP3 regulated and downregulated, respectively, the expression of the NbAGO5 gene. Upon virus infection, NbNAC42 played an important role in regulating the expression of NbAGO5. Together, these results provide new insights into the modulation of the defense mechanism of N. benthamiana against viruses. This virus inducible promoter could be an ideal candidate to drive the target gene expression that could improve the anti-virus abilities of crops in the future.
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Affiliation(s)
- Yuan-Dun Ke
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Ying-Wen Huang
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | | | - Chung-Chi Hu
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Chuan-Ming Yeh
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Nobutaka Mitsuda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Na-Sheng Lin
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei City, Taiwan
| | - Yau-Heiu Hsu
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
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63
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Bioinformatic Analysis Predicts a Novel Genetic Module Related to Triple Gene and Binary Movement Blocks of Plant Viruses: Tetra-Cistron Movement Block. Biomolecules 2022; 12:biom12070861. [PMID: 35883420 PMCID: PMC9313169 DOI: 10.3390/biom12070861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/14/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022] Open
Abstract
Previous studies have shown that the RNA genomes of some plant viruses encode two related genetic modules required for virus movement over the host body, containing two or three genes and named the binary movement block (BMB) and triple gene block (TGB), respectively. In this paper, we predict a novel putative-related movement gene module, called the tetra-cistron movement block (TCMB), in the virus-like transcriptome assemblies of the moss Dicranum scoparium and the Antarctic flowering plant Colobanthus quitensis. These TCMBs are encoded by smaller RNA components of putative two-component viruses related to plant benyviruses. Similar to the RNA2 of benyviruses, TCMB-containing RNAs have the 5′-terminal coat protein gene and include the RNA helicase gene which is followed by two small overlapping cistrons encoding hydrophobic proteins with a distant sequence similarity to the TGB2 and TGB3 proteins. Unlike TGB, TCMB also includes a fourth 5′-terminal gene preceding the helicase gene and coding for a protein showing a similarity to the double-stranded RNA-binding proteins of the DSRM AtDRB-like superfamily. Additionally, based on phylogenetic analysis, we suggest the involvement of replicative beny-like helicases in the evolution of the BMB and TCMB movement genetic modules.
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64
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Roles of RNA silencing in viral and non-viral plant immunity and in the crosstalk between disease resistance systems. Nat Rev Mol Cell Biol 2022; 23:645-662. [PMID: 35710830 DOI: 10.1038/s41580-022-00496-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/04/2022] [Indexed: 11/08/2022]
Abstract
RNA silencing is a well-established antiviral immunity system in plants, in which small RNAs guide Argonaute proteins to targets in viral RNA or DNA, resulting in virus repression. Virus-encoded suppressors of silencing counteract this defence system. In this Review, we discuss recent findings about antiviral RNA silencing, including the movement of RNA through plasmodesmata and the differentiation between plant self and viral RNAs. We also discuss the emerging role of RNA silencing in plant immunity against non-viral pathogens. This immunity is mediated by transkingdom movement of RNA into and out of the infected plant cells in vesicles or as extracellular nucleoproteins and, like antiviral immunity, is influenced by the silencing suppressors encoded in the pathogens' genomes. Another effect of RNA silencing on general immunity involves host-encoded small RNAs, including microRNAs, that regulate NOD-like receptors and defence signalling pathways in the innate immunity system of plants. These RNA silencing pathways form a network of processes with both positive and negative effects on the immune systems of plants.
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65
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Gómez G, Marquez-Molins J, Martinez G, Pallas V. Plant epigenome alterations: an emergent player in viroid-host interactions. Virus Res 2022; 318:198844. [DOI: 10.1016/j.virusres.2022.198844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/31/2022] [Accepted: 06/05/2022] [Indexed: 10/18/2022]
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66
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Fan L, He C, Gao D, Xu T, Xing F, Yan J, Zhan B, Li S, Wang H. Identification of Silencing Suppressor Protein Encoded by Strawberry Mottle Virus. FRONTIERS IN PLANT SCIENCE 2022; 13:786489. [PMID: 35712581 PMCID: PMC9195133 DOI: 10.3389/fpls.2022.786489] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Strawberry mottle virus (SMoV) is associated with strawberry decline disease, causing losses to fruit yield and quality. In this study, using a screening system that enables detection of both local and systemic plant host (RNA silencing) defense responses, we found that Pro2Glu and P28, encoded by SMoV RNA2 genome, functioned to suppress local and systemic RNA silencing triggered by single- but not double-stranded GFP RNA. Subcellular localization assay revealed that both Pro2Glu and P28 were localized to nucleus and cytoplasm. The deletion of 11 amino acid residues at the C-terminus destabilized Pro2Glu protein, and the disruption of two conserved GW motifs deprived Pro2Glu of ability to suppress RNA silencing. Additionally, SMoV Pro2Glu and P28 enhanced the accumulation of potato virus X (PVX) in Nicotiana benthamiana 22 days post-infiltration, and P28 exacerbated significantly the symptoms of PVX. Collectively, these data indicate that the genome of SMoV RNA2 encodes two suppressors of RNA silencing. This is the first identification of a stramovirus suppressor of RNA silencing.
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Affiliation(s)
- Lingjiao Fan
- Department of Fruit Science, College of Horticulture, China Agricultural University, Beijing, China
| | - Chengyong He
- Department of Fruit Science, College of Horticulture, China Agricultural University, Beijing, China
| | - Dehang Gao
- Department of Fruit Science, College of Horticulture, China Agricultural University, Beijing, China
| | - Tengfei Xu
- Department of Fruit Science, College of Horticulture, China Agricultural University, Beijing, China
| | - Fei Xing
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiaqi Yan
- Department of Fruit Science, College of Horticulture, China Agricultural University, Beijing, China
| | - Binhui Zhan
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Shifang Li
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongqing Wang
- Department of Fruit Science, College of Horticulture, China Agricultural University, Beijing, China
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67
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Liu S, Chen M, Li R, Li WX, Gal-On A, Jia Z, Ding SW. Identification of positive and negative regulators of antiviral RNA interference in Arabidopsis thaliana. Nat Commun 2022; 13:2994. [PMID: 35637208 PMCID: PMC9151786 DOI: 10.1038/s41467-022-30771-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 05/18/2022] [Indexed: 02/06/2023] Open
Abstract
Virus-host coevolution often drives virus immune escape. However, it remains unknown whether natural variations of plant virus resistance are enriched in genes of RNA interference (RNAi) pathway known to confer essential antiviral defense in plants. Here, we report two genome-wide association study screens to interrogate natural variation among wild-collected Arabidopsis thaliana accessions in quantitative resistance to the endemic cucumber mosaic virus (CMV). We demonstrate that the highest-ranked gene significantly associated with resistance from both screens acts to regulate antiviral RNAi in ecotype Columbia-0. One gene, corresponding to Reduced Dormancy 5 (RDO5), enhances resistance by promoting amplification of the virus-derived small interfering RNAs (vsiRNAs). Interestingly, the second gene, designated Antiviral RNAi Regulator 1 (VIR1), dampens antiviral RNAi so its genetic inactivation by CRISPR/Cas9 editing enhances both vsiRNA production and CMV resistance. Our findings identify positive and negative regulators of the antiviral RNAi defense that may play important roles in virus-host coevolution.
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Affiliation(s)
- Si Liu
- Department of Microbiology & Plant Pathology, University of California, Riverside, CA, USA
| | - Meijuan Chen
- Department of Microbiology & Plant Pathology, University of California, Riverside, CA, USA
| | - Ruidong Li
- Department of Botany & Plant Sciences, University of California, Riverside, CA, USA
| | - Wan-Xiang Li
- Department of Microbiology & Plant Pathology, University of California, Riverside, CA, USA
| | - Amit Gal-On
- Department of Plant Pathology and Weed Science, Volcani Center, Rishon LeZion, 7528809, Israel
| | - Zhenyu Jia
- Department of Botany & Plant Sciences, University of California, Riverside, CA, USA.
| | - Shou-Wei Ding
- Department of Microbiology & Plant Pathology, University of California, Riverside, CA, USA.
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68
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Li WX, Ding SW. Mammalian viral suppressors of RNA interference. Trends Biochem Sci 2022; 47:978-988. [PMID: 35618579 DOI: 10.1016/j.tibs.2022.05.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 04/14/2022] [Accepted: 05/02/2022] [Indexed: 12/18/2022]
Abstract
The antiviral defense directed by the RNAi pathway employs distinct specificity and effector mechanisms compared with other immune responses. The specificity of antiviral RNAi is programmed by siRNAs processed from virus-derived double-stranded RNA by Dicer endonuclease. Argonaute-containing RNA-induced silencing complex loaded with the viral siRNAs acts as the effector to mediate specific virus clearance by RNAi. Recent studies have provided evidence for the production and antiviral function of virus-derived siRNAs in both undifferentiated and differentiated mammalian cells infected with a range of RNA viruses when the cognate virus-encoded suppressor of RNAi (VSR) is rendered nonfunctional. In this review, we discuss the function, mechanism, and evolutionary origin of the validated mammalian VSRs and cell culture assays for their identification.
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Affiliation(s)
- Wan-Xiang Li
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA, USA
| | - Shou-Wei Ding
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA, USA.
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69
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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: 31] [Impact Index Per Article: 15.5] [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.
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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;
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70
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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: 12] [Impact Index Per Article: 6.0] [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.
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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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71
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Chen J, Zheng L, Shi X, Zhang S, Tan X, Zhao X, Lu B, Ye Q, Miao S, Liu Y, Zhang D. The nonstructural protein NSs encoded by tomato zonate spot virus suppresses RNA silencing by interacting with NbSGS3. MOLECULAR PLANT PATHOLOGY 2022; 23:707-719. [PMID: 35184365 PMCID: PMC8995058 DOI: 10.1111/mpp.13192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 01/23/2022] [Accepted: 01/25/2022] [Indexed: 05/21/2023]
Abstract
Viral suppressors of RNA silencing (VSRs) are encoded by diverse viruses to counteract the RNA silencing-mediated defence mounted by the virus-infected host cells. In this study, we identified the NSs protein encoded by tomato zonate spot virus (TZSV) as a potent VSR, and used a potato virus X (PVX)-based heterologous expression system to demonstrate TZSV NSs as a viral pathogenicity factor that intensified PVX symptoms in Nicotiana benthamiana. We then used a yeast two-hybrid screen to identify the suppressor of gene silencing 3 protein of N. benthamiana (NbSGS3), a known component of the plant RNA silencing pathway, as an interaction partner of TZSV NSs. We verified this interaction in plant cells with bimolecular fluorescence complementation, subcellular colocalization, and co-immunoprecipitation. We further revealed that the NSs-NbSGS3 interaction correlated with the VSR activity of TZSV NSs. TZSV NSs reduced the concentration of NbSGS3 protein in plant cells, probably through the ubiquitination and autophagy pathways. Interestingly, TZSV infection, but not NSs overexpression, significantly up-regulated the NbSGS3 transcript levels. Our data indicate that TZSV NSs suppresses RNA silencing of the host plant and enhances TZSV pathogenicity through its interaction with NbSGS3. This study reveals a novel molecular mechanism of NSs-mediated suppression of plant host antiviral defence.
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Affiliation(s)
- Jianbin Chen
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Limin Zheng
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Xiaobin Shi
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Songbai Zhang
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Xinqiu Tan
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Xingyue Zhao
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Bingxin Lu
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Qian Ye
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Shuyue Miao
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Yong Liu
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
| | - Deyong Zhang
- Longping BranchGraduate School of Hunan UniversityChangshaChina
- Hunan Plant Protection InstituteHunan Academy of Agricultural SciencesChangshaChina
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72
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Pertermann R, Golbik RP, Tamilarasan S, Gursinsky T, Gago-Zachert S, Pantaleo V, Thondorf I, Behrens SE. RNA and Protein Determinants Mediate Differential Binding of miRNAs by a Viral Suppressor of RNA Silencing Thus Modulating Antiviral Immune Responses in Plants. Int J Mol Sci 2022; 23:4977. [PMID: 35563369 PMCID: PMC9103804 DOI: 10.3390/ijms23094977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 01/27/2023] Open
Abstract
Many plant viruses express suppressor proteins (VSRs) that can inhibit RNA silencing, a central component of antiviral plant immunity. The most common activity of VSRs is the high-affinity binding of virus-derived siRNAs and thus their sequestration from the silencing process. Since siRNAs share large homologies with miRNAs, VSRs like the Tombusvirus p19 may also bind miRNAs and in this way modulate cellular gene expression at the post-transcriptional level. Interestingly, the binding affinity of p19 varies considerably between different miRNAs, and the molecular determinants affecting this property have not yet been adequately characterized. Addressing this, we analyzed the binding of p19 to the miRNAs 162 and 168, which regulate the expression of the important RNA silencing constituents Dicer-like 1 (DCL1) and Argonaute 1 (AGO1), respectively. p19 binds miRNA162 with similar high affinity as siRNA, whereas the affinity for miRNA168 is significantly lower. We show that specific molecular features, such as mismatches and 'G-U wobbles' on the RNA side and defined amino acid residues on the VSR side, mediate this property. Our observations highlight the remarkable adaptation of VSR binding affinities to achieve differential effects on host miRNA activities. Moreover, they show that even minimal changes, i.e., a single base pair in a miRNA duplex, can have significant effects on the efficiency of the plant antiviral immune response.
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Affiliation(s)
- Robert Pertermann
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
| | - Ralph Peter Golbik
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
| | - Selvaraj Tamilarasan
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
| | - Torsten Gursinsky
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
| | - Selma Gago-Zachert
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
| | - Vitantonio Pantaleo
- Department of Biology, Agricultural and Food Sciences, Institute for Sustainable Plant Protection, Bari Unit, CNR, 70126 Bari, Italy;
| | - Iris Thondorf
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
| | - Sven-Erik Behrens
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Saale, 06120 Halle, Germany; (R.P.); (R.P.G.); (S.T.); (T.G.); (S.G.-Z.); (I.T.)
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73
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Villegas-Estrada B, Sánchez MA, Valencia-Jiménez A. Foliar Infiltration of Virus-Derived Small Hairpin RNAs Triggers the RNAi Mechanism against the Cucumber Mosaic Virus. Int J Mol Sci 2022; 23:4938. [PMID: 35563329 PMCID: PMC9104436 DOI: 10.3390/ijms23094938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/14/2022] [Accepted: 04/21/2022] [Indexed: 11/16/2022] Open
Abstract
Post-transcriptional gene silencing (PTGS) is an evolutionarily conserved plant defense mechanism against viruses. This paper aimed to evaluate a dsDNA construct (77 bp) as a template for in vitro production of virus-derived artificial small hairpin RNAs (shRNAs) and test for their potential to trigger the RNAi mechanism in Nicotiana benthamiana plants against CMV after their foliar infiltration. This approach allowed for the production of significant amounts of shRNAs (60-mers) quickly and easily. The gene silencing was confirmed using polymerase chain reaction (PCR), immunological-based assays, and real-time PCR (qPCR). The highest levels of gene silencing were recorded for mRNAs coding for replication protein (ORF1a), the viral suppressor of RNA silencing (ORF2b), and the capsid protein (ORF3b), with 98, 94, and 70% of total transcript silencing, respectively. This protocol provides an alternative to producing significant shRNAs that can effectively trigger the RNAi mechanism against CMV.
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Affiliation(s)
| | | | - Arnubio Valencia-Jiménez
- Departamento de Producción Agropecuaria, Universidad de Caldas, Manizales 170004, Caldas, Colombia;
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74
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Urrutia CD, Romay G, Shaw BD, Verchot J. Advancing the Rose Rosette Virus Minireplicon and Encapsidation System by Incorporating GFP, Mutations, and the CMV 2b Silencing Suppressor. Viruses 2022; 14:836. [PMID: 35458566 PMCID: PMC9031449 DOI: 10.3390/v14040836] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/01/2022] [Accepted: 04/13/2022] [Indexed: 11/26/2022] Open
Abstract
Plant infecting emaraviruses have segmented negative strand RNA genomes and little is known about their infection cycles due to the lack of molecular tools for reverse genetic studies. Therefore, we innovated a rose rosette virus (RRV) minireplicon containing the green fluorescent protein (GFP) gene to study the molecular requirements for virus replication and encapsidation. Sequence comparisons among RRV isolates and structural modeling of the RNA dependent RNA polymerase (RdRp) and nucleocapsid (N) revealed three natural mutations of the type species isolate that we reverted to the common species sequences: (a) twenty-one amino acid truncations near the endonuclease domain (named delA), (b) five amino acid substitutions near the putative viral RNA binding loop (subT), and (c) four amino acid substitutions in N (NISE). The delA and subT in the RdRp influenced the levels of GFP, gRNA, and agRNA at 3 but not 5 days post inoculation (dpi), suggesting these sequences are essential for initiating RNA synthesis and replication. The NISE mutation led to sustained GFP, gRNA, and agRNA at 3 and 5 dpi indicating that the N supports continuous replication and GFP expression. Next, we showed that the cucumber mosaic virus (CMV strain FNY) 2b singularly enhanced GFP expression and RRV replication. Including agRNA2 with the RRV replicon produced observable virions. In this study we developed a robust reverse genetic system for investigations into RRV replication and virion assembly that could be a model for other emaravirus species.
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Affiliation(s)
| | | | | | - Jeanmarie Verchot
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77845, USA; (C.D.U.); (G.R.); (B.D.S.)
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75
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Hacquard T, Clavel M, Baldrich P, Lechner E, Pérez-Salamó I, Schepetilnikov M, Derrien B, Dubois M, Hammann P, Kuhn L, Brun D, Bouteiller N, Baumberger N, Vaucheret H, Meyers BC, Genschik P. The Arabidopsis F-box protein FBW2 targets AGO1 for degradation to prevent spurious loading of illegitimate small RNA. Cell Rep 2022; 39:110671. [PMID: 35417704 PMCID: PMC9035678 DOI: 10.1016/j.celrep.2022.110671] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 12/14/2021] [Accepted: 03/22/2022] [Indexed: 11/03/2022] Open
Abstract
RNA silencing is a conserved mechanism in eukaryotes involved in development and defense against viruses. In plants, ARGONAUTE1 (AGO1) protein plays a central role in both microRNA- and small interfering RNA-directed silencing, and its expression is regulated at multiple levels. Here, we report that the F-box protein FBW2 assembles an SCF complex that selectively targets for proteolysis AGO1 when it is unloaded and mutated. Although FBW2 loss of function does not lead to strong growth or developmental defects, it significantly increases RNA-silencing activity. Interestingly, under conditions in which small-RNA accumulation is affected, the failure to degrade AGO1 in fbw2 mutants becomes more deleterious for the plant. Accordingly, the non-degradable AGO1 protein assembles high-molecular-weight complexes and binds illegitimate small RNA, leading to off-target cleavage. Therefore, control of AGO1 homeostasis by FBW2 plays an important role in quality control of RNA silencing.
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Affiliation(s)
- Thibaut Hacquard
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Marion Clavel
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | | | - Esther Lechner
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Imma Pérez-Salamó
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Mikhail Schepetilnikov
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Benoît Derrien
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Marieke Dubois
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Philippe Hammann
- Plateforme Protéomique Strasbourg Esplanade du CNRS, Université de Strasbourg, 67084 Strasbourg, France
| | - Lauriane Kuhn
- Plateforme Protéomique Strasbourg Esplanade du CNRS, Université de Strasbourg, 67084 Strasbourg, France
| | - Danaé Brun
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Nathalie Bouteiller
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Nicolas Baumberger
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France
| | - Hervé Vaucheret
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, 78000 Versailles, France
| | - Blake C Meyers
- Donald Danforth Plant Science Center, Saint Louis 63132, MO, USA; Division of Plant Science and Technology, University of Missouri, Columbia, MO 65211, USA
| | - Pascal Genschik
- Institut de biologie moléculaire des plantes, CNRS, Université de Strasbourg, 12, rue du Général Zimmer, 67084 Strasbourg, France.
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76
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Ivanova Z, Minkov G, Gisel A, Yahubyan G, Minkov I, Toneva V, Baev V. The Multiverse of Plant Small RNAs: How Can We Explore It?
. Int J Mol Sci 2022; 23:ijms23073979. [PMID: 35409340 PMCID: PMC8999349 DOI: 10.3390/ijms23073979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 03/28/2022] [Accepted: 03/31/2022] [Indexed: 12/22/2022] Open
Abstract
Plant small RNAs (sRNAs) are a heterogeneous group of noncoding RNAs with a length of 20–24 nucleotides that are widely studied due to their importance as major regulators in various biological processes. sRNAs are divided into two main classes—microRNAs (miRNAs) and small interfering RNAs (siRNAs)—which differ in their biogenesis and functional pathways. Their identification and enrichment with new structural variants would not be possible without the use of various high-throughput sequencing (NGS) techniques, allowing for the detection of the total population of sRNAs in plants. Classifying sRNAs and predicting their functional role based on such high-performance datasets is a nontrivial bioinformatics task, as plants can generate millions of sRNAs from a variety of biosynthetic pathways. Over the years, many computing tools have been developed to meet this challenge. Here, we review more than 35 tools developed specifically for plant sRNAs over the past few years and explore some of their basic algorithms for performing tasks related to predicting, identifying, categorizing, and quantifying individual sRNAs in plant samples, as well as visualizing the results of these analyzes. We believe that this review will be practical for biologists who want to analyze their plant sRNA datasets but are overwhelmed by the number of tools available, thus answering the basic question of how to choose the right one for a particular study.
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Affiliation(s)
- Zdravka Ivanova
- Institute of Molecular Biology and Biotechnologies, 4108 Markovo, Bulgaria; (Z.I.); (G.M.); (I.M.); (V.T.)
| | - Georgi Minkov
- Institute of Molecular Biology and Biotechnologies, 4108 Markovo, Bulgaria; (Z.I.); (G.M.); (I.M.); (V.T.)
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria;
| | - Andreas Gisel
- Institute of Biomedical Technologies (ITB), CNR, 70126 Bari, Italy;
| | - Galina Yahubyan
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria;
| | - Ivan Minkov
- Institute of Molecular Biology and Biotechnologies, 4108 Markovo, Bulgaria; (Z.I.); (G.M.); (I.M.); (V.T.)
- Center of Plant System Biology and Biotechnology, 4000 Plovdiv, Bulgaria
| | - Valentina Toneva
- Institute of Molecular Biology and Biotechnologies, 4108 Markovo, Bulgaria; (Z.I.); (G.M.); (I.M.); (V.T.)
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria;
| | - Vesselin Baev
- Institute of Molecular Biology and Biotechnologies, 4108 Markovo, Bulgaria; (Z.I.); (G.M.); (I.M.); (V.T.)
- Department of Plant Physiology and Molecular Biology, University of Plovdiv, 4000 Plovdiv, Bulgaria;
- Correspondence:
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77
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Miller J, Burch-Smith TM, Ganusov VV. Mathematical Modeling Suggests Cooperation of Plant-Infecting Viruses. Viruses 2022; 14:741. [PMID: 35458472 PMCID: PMC9029262 DOI: 10.3390/v14040741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/12/2022] [Accepted: 03/25/2022] [Indexed: 02/05/2023] Open
Abstract
Viruses are major pathogens of agricultural crops. Viral infections often start after the virus enters the outer layer of a tissue, and many successful viruses, after local replication in the infected tissue, are able to spread systemically. Quantitative details of virus dynamics in plants, however, are poorly understood, in part, because of the lack of experimental methods which allow the accurate measurement of the degree of infection in individual plant tissues. Recently, a group of researchers followed the kinetics of infection of individual cells in leaves of Nicotiana tabacum plants using Tobacco etch virus (TEV) expressing either Venus or blue fluorescent protein (BFP). Assuming that viral spread occurs from lower to upper leaves, the authors fitted a simple mathematical model to the frequency of cellular infection by the two viral variants found using flow cytometry. While the original model could accurately describe the kinetics of viral spread locally and systemically, we found that many alternative versions of the model, for example, if viral spread starts at upper leaves and progresses to lower leaves or when virus dissemination is stopped due to an immune response, fit the data with reasonable quality, and yet with different parameter estimates. These results strongly suggest that experimental measurements of the virus infection in individual leaves may not be sufficient to identify the pathways of viral dissemination between different leaves and reasons for viral control. We propose experiments that may allow discrimination between the alternatives. By analyzing the kinetics of coinfection of individual cells by Venus and BFP strains of TEV we found a strong deviation from the random infection model, suggesting cooperation between the two strains when infecting plant cells. Importantly, we showed that many mathematical models on the kinetics of coinfection of cells with two strains could not adequately describe the data, and the best fit model needed to assume (i) different susceptibility of uninfected cells to infection by two viruses locally in the leaf vs. systemically from other leaves, and (ii) decrease in the infection rate depending on the fraction of uninfected cells which could be due to a systemic immune response. Our results thus demonstrate the difficulty in reaching definite conclusions from extensive and yet limited experimental data and provide evidence of potential cooperation between different viral variants infecting individual cells in plants.
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Affiliation(s)
- Joshua Miller
- Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA;
| | | | - Vitaly V. Ganusov
- Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA;
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
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78
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Wang Y, Pruitt RN, Nürnberger T, Wang Y. Evasion of plant immunity by microbial pathogens. Nat Rev Microbiol 2022; 20:449-464. [PMID: 35296800 DOI: 10.1038/s41579-022-00710-3] [Citation(s) in RCA: 126] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/16/2022] [Indexed: 12/21/2022]
Abstract
Plant pathogenic viruses, bacteria, fungi and oomycetes cause destructive diseases in natural habitats and agricultural settings, thereby threatening plant biodiversity and global food security. The capability of plants to sense and respond to microbial infection determines the outcome of plant-microorganism interactions. Host-adapted microbial pathogens exploit various infection strategies to evade or counter plant immunity and eventually establish a replicative niche. Evasion of plant immunity through dampening host recognition or the subsequent immune signalling and defence execution is a crucial infection strategy used by different microbial pathogens to cause diseases, underpinning a substantial obstacle for efficient deployment of host genetic resistance genes for sustainable disease control. In this Review, we discuss current knowledge of the varied strategies microbial pathogens use to evade the complicated network of plant immunity for successful infection. In addition, we discuss how to exploit this knowledge to engineer crop resistance.
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Affiliation(s)
- Yan Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China.,The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing, China
| | - Rory N Pruitt
- Centre for Molecular Biology of Plants (ZMBP), University of Tübingen, Tübingen, Germany
| | - Thorsten Nürnberger
- Centre for Molecular Biology of Plants (ZMBP), University of Tübingen, Tübingen, Germany.,Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa
| | - Yuanchao Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China. .,The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing, China.
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79
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Glushkevich A, Spechenkova N, Fesenko I, Knyazev A, Samarskaya V, Kalinina NO, Taliansky M, Love AJ. Transcriptomic Reprogramming, Alternative Splicing and RNA Methylation in Potato ( Solanum tuberosum L.) Plants in Response to Potato Virus Y Infection. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11050635. [PMID: 35270104 PMCID: PMC8912425 DOI: 10.3390/plants11050635] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/09/2022] [Accepted: 02/22/2022] [Indexed: 05/05/2023]
Abstract
Plant-virus interactions are greatly influenced by environmental factors such as temperatures. In virus-infected plants, enhanced temperature is frequently associated with more severe symptoms and higher virus content. However, the mechanisms involved in controlling the temperature regulation of plant-virus interactions are poorly characterised. To elucidate these further, we analysed the responses of potato plants cv Chicago to infection by potato virus Y (PVY) at normal (22 °C) and elevated temperature (28 °C), the latter of which is known to significantly increase plant susceptibility to PVY. Using RNAseq analysis, we showed that single and combined PVY and heat-stress treatments caused dramatic changes in gene expression, affecting the transcription of both protein-coding and non-coding RNAs. Among the newly identified genes responsive to PVY infection, we found genes encoding enzymes involved in the catalysis of polyamine formation and poly ADP-ribosylation. We also identified a range of novel non-coding RNAs which were differentially produced in response to single or combined PVY and heat stress, that consisted of antisense RNAs and RNAs with miRNA binding sites. Finally, to gain more insights into the potential role of alternative splicing and epitranscriptomic RNA methylation during combined stress conditions, direct RNA nanopore sequencing was performed. Our findings offer insights for future studies of functional links between virus infections and transcriptome reprogramming, RNA methylation and alternative splicing.
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Affiliation(s)
- Anna Glushkevich
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (A.G.); (N.S.); (I.F.); (A.K.); (V.S.)
| | - Nadezhda Spechenkova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (A.G.); (N.S.); (I.F.); (A.K.); (V.S.)
| | - Igor Fesenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (A.G.); (N.S.); (I.F.); (A.K.); (V.S.)
| | - Andrey Knyazev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (A.G.); (N.S.); (I.F.); (A.K.); (V.S.)
| | - Viktoriya Samarskaya
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (A.G.); (N.S.); (I.F.); (A.K.); (V.S.)
| | - Natalia O. Kalinina
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia;
| | - Michael Taliansky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (A.G.); (N.S.); (I.F.); (A.K.); (V.S.)
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
- Correspondence: (M.T.); (A.J.L.)
| | - Andrew J. Love
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
- Correspondence: (M.T.); (A.J.L.)
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80
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Khan ZA, Kumar R, Dasgupta I. CRISPR/Cas-Mediated Resistance against Viruses in Plants. Int J Mol Sci 2022; 23:ijms23042303. [PMID: 35216418 PMCID: PMC8879314 DOI: 10.3390/ijms23042303] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 01/29/2022] [Accepted: 02/02/2022] [Indexed: 11/16/2022] Open
Abstract
CRISPR/Cas9 provides a robust and widely adaptable system with enormous potential for genome editing directed towards generating useful products. It has been used extensively to generate resistance against viruses infecting plants with more effective and prolonged efficiency as compared with previous antiviral approaches, thus holding promise to alleviate crop losses. In this review, we have discussed the reports of CRISPR/Cas-based virus resistance strategies against plant viruses. These strategies include approaches targeting single or multiple genes (or non-coding region) in the viral genome and targeting host factors essential for virus propagation. In addition, the utilization of base editing has been discussed to generate transgene-free plants resistant to viruses. This review also compares the efficiencies of these approaches. Finally, we discuss combinatorial approaches, including multiplexing, to increase editing efficiency and bypass the generation of escape mutants.
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81
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Zhao S, Chen G, Kong X, Chen N, Wu X. BmNPV p35 Reduces the Accumulation of Virus-Derived siRNAs and Hinders the Function of siRNAs to Facilitate Viral Infection. Front Immunol 2022; 13:845268. [PMID: 35251046 PMCID: PMC8895250 DOI: 10.3389/fimmu.2022.845268] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 01/25/2022] [Indexed: 11/25/2022] Open
Abstract
Antiviral immunity involves various mechanisms and responses, including the RNA interference (RNAi) pathway. During long-term coevolution, viruses have gained the ability to evade this defense by encoding viral suppressors of RNAi (VSRs). It was reported that p35 of baculovirus can inhibit cellular small interference RNA (siRNA) pathway; however, the molecular mechanisms underlying p35 as a VSR remain largely unclear. Here, we showed that p35 of Bombyx mori nucleopolyhedrovirus (BmNPV) reduces the accumulation of virus-derived siRNAs (vsiRNAs) mapped to a particular region in the viral genome, leading to an increased expression of the essential genes in this region, and revealed that p35 disrupts the function of siRNAs by preventing them from loading into Argonaute-2 (Ago2). This repressive effect on the cellular siRNA pathway enhances the replication of BmNPV. Thus, our findings illustrate for the first time the inhibitory mechanism of a baculovirus VSR and how this effect influences viral infection.
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Affiliation(s)
- Shudi Zhao
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, Hangzhou, China
| | - Guanping Chen
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, Hangzhou, China
| | - Xiangshuo Kong
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, Hangzhou, China
| | - Nan Chen
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, Hangzhou, China
| | - Xiaofeng Wu
- College of Animal Sciences, Zhejiang University, Hangzhou, China
- Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, Hangzhou, China
- *Correspondence: Xiaofeng Wu,
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82
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Wang D, Dawadi B, Qu J, Ye J. Light-Engineering Technology for Enhancing Plant Disease Resistance. FRONTIERS IN PLANT SCIENCE 2022; 12:805614. [PMID: 35251062 PMCID: PMC8891579 DOI: 10.3389/fpls.2021.805614] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 12/31/2021] [Indexed: 06/14/2023]
Abstract
Insect vector-borne diseases are a major constraint to a wide variety of crops. Plants integrate environmental light and internal signalings to defend dual stresses both from the vector insects and vector-transmitted pathogens. In this review, we highlight a studies that demonstrate how light regulates plants deploying mechanisms against vector-borne diseases. Four major host defensive pathways involved in the host defense network against multiple biotic stresses are reviewed: innate immunity, phytohormone signaling, RNA interference, and protein degradation. The potential with light-engineering technology with light emitting diodes (LEDs) and genome engineering technology for fine-tuning crop defense and yield are also discussed.
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Affiliation(s)
- Duan Wang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Bishnu Dawadi
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Jing Qu
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Jian Ye
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
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83
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Oliver C, Annacondia ML, Wang Z, Jullien PE, Slotkin RK, Köhler C, Martinez G. The miRNome function transitions from regulating developmental genes to transposable elements during pollen maturation. THE PLANT CELL 2022; 34:784-801. [PMID: 34755870 PMCID: PMC8824631 DOI: 10.1093/plcell/koab280] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 11/04/2021] [Indexed: 06/13/2023]
Abstract
Animal and plant microRNAs (miRNAs) are essential for the spatio-temporal regulation of development. Together with this role, plant miRNAs have been proposed to target transposable elements (TEs) and stimulate the production of epigenetically active small interfering RNAs. This activity is evident in the plant male gamete containing structure, the male gametophyte or pollen grain. How the dual role of plant miRNAs, regulating both genes and TEs, is integrated during pollen development and which mRNAs are regulated by miRNAs in this cell type at a genome-wide scale are unknown. Here, we provide a detailed analysis of miRNA dynamics and activity during pollen development in Arabidopsis thaliana using small RNA and degradome parallel analysis of RNA end high-throughput sequencing. Furthermore, we uncover miRNAs loaded into the two main active Argonaute (AGO) proteins in the uninuclear and mature pollen grain, AGO1 and AGO5. Our results indicate that the developmental progression from microspore to mature pollen grain is characterized by a transition from miRNAs targeting developmental genes to miRNAs regulating TE activity.
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Affiliation(s)
- Cecilia Oliver
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Maria Luz Annacondia
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
| | - Zhenxing Wang
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
- College of Horticulture and State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs and Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, Nanjing Agricultural University, Nanjing 210095, China
| | - Pauline E Jullien
- Institute of Plant Sciences, University of Bern, Bern 3013, Switzerland
| | - R Keith Slotkin
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
- Division of Biological Sciences, University of Missouri Columbia, Columbia, Missouri 65201, USA
| | - Claudia Köhler
- Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala 75007, Sweden
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany
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84
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Murai H, Atsumaru K, Mochizuki T. Effect of mutations in the 2b protein of tomato aspermy virus on RNA silencing suppressor activity, virulence, and virus-induced gene silencing. Arch Virol 2022; 167:471-481. [PMID: 34978608 DOI: 10.1007/s00705-021-05344-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/15/2021] [Indexed: 11/25/2022]
Abstract
Tomato aspermy virus (TAV) and cucumber mosaic virus (CMV) belong to the genus Cucumovirus in the family Bromoviridae. The cucumovirus 2b protein is one of the first identified viral suppressors of RNA silencing (VSR). The cucumovirus 2b protein contains a conserved amino acid motif consisting of several highly conserved amino acid residues. Here, we demonstrate that the TAV 2b protein N-terminal region, Arg46, Ser40, and Ser42 as well as the CMV 2b protein are essential for VSR activity, virulence, and viral RNA accumulation. Furthermore, we developed the first TAV-induced gene silencing (VIGS) vector. In contrast to other cucumovirus vectors, such as CMV and peanut stunt virus, the TAV vector did not induce a silencing phenotype in Nicotiana benthamiana when 2b protein VSR activity was retained. These findings suggest that the cucumovirus 2b proteins share amino acid residues for VSR activity but may have different roles in VIGS induction.
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Affiliation(s)
- Hirotomo Murai
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan
| | - Kenta Atsumaru
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan
| | - Tomofumi Mochizuki
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan.
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85
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Zhao JH, Guo HS. RNA silencing: From discovery and elucidation to application and perspectives. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 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] [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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86
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Sun S, Ren Y, Wang D, Farooq T, He Z, Zhang C, Li S, Yang X, Zhou X. A group I WRKY transcription factor regulates mulberry mosaic dwarf-associated virus-triggered cell death in Nicotiana benthamiana. MOLECULAR PLANT PATHOLOGY 2022; 23:237-253. [PMID: 34738705 PMCID: PMC8743015 DOI: 10.1111/mpp.13156] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 05/27/2023]
Abstract
Geminiviruses constitute the largest group of known plant viruses and cause devastating losses to a wide range of crops and woody plants globally. Mulberry mosaic dwarf-associated virus (MMDaV), identified from Chinese mulberry trees via small RNA-based deep sequencing, is a divergent monopartite geminivirus belonging to the genus Mulcrilevirus of the family Geminiviridae. Previous studies have shown that plants employ multiple layers of defence to protect themselves from geminivirus infection. The interplay between plant and MMDaV is nevertheless less studied. This study presents evidence that MMDaV triggers hypersensitive response (HR)-mediated antiviral defence in Nicotiana benthamiana plants. We show that the RepA protein of MMDaV is engaged in HR-type cell death induction. We find that the RepA mutants with compromised nuclear localization ability impair their capabilities of cell death induction. Virus-induced gene silencing of the key components of the R protein-mediated signalling pathway reveals that down-regulation of the nucleus-targeting NbWRKY1 alleviates the cell death induction activity of RepA. We further demonstrate that RepA up-regulates the transcript level of NbWRKY1. Furthermore, expression of RepA in N. benthamiana confers plant resistance against two begomoviruses. We propose that plant resistance against RepA can be potentially used to improve plant defence against geminiviruses in crops.
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Affiliation(s)
- Shaoshuang Sun
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Yanxiang Ren
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil MicrobiologyCollege of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Dongxue Wang
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Tahir Farooq
- Plant Protection Research InstituteGuangdong Academy of Agricultural SciencesGuangzhouChina
| | - Zifu He
- Plant Protection Research InstituteGuangdong Academy of Agricultural SciencesGuangzhouChina
| | - Chao Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Shifang Li
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Xiuling Yang
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina
- State Key Laboratory of Rice Biology, Institute of BiotechnologyZhejiang UniversityHangzhouChina
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87
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Wang C, Jiang F, Zhu S. Complex Small RNA-mediated Regulatory Networks between Viruses/Viroids/Satellites and Host Plants. Virus Res 2022; 311:198704. [DOI: 10.1016/j.virusres.2022.198704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 01/16/2022] [Accepted: 01/29/2022] [Indexed: 12/26/2022]
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88
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Improving Protein Quantity and Quality—The Next Level of Plant Molecular Farming. Int J Mol Sci 2022; 23:ijms23031326. [PMID: 35163249 PMCID: PMC8836236 DOI: 10.3390/ijms23031326] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 01/21/2022] [Accepted: 01/22/2022] [Indexed: 12/15/2022] Open
Abstract
Plants offer several unique advantages in the production of recombinant pharmaceuticals for humans and animals. Although numerous recombinant proteins have been expressed in plants, only a small fraction have been successfully put into use. The hugely distinct expression systems between plant and animal cells frequently cause insufficient yield of the recombinant proteins with poor or undesired activity. To overcome the issues that greatly constrain the development of plant-produced pharmaceuticals, great efforts have been made to improve expression systems and develop alternative strategies to increase both the quantity and quality of the recombinant proteins. Recent technological revolutions, such as targeted genome editing, deconstructed vectors, virus-like particles, and humanized glycosylation, have led to great advances in plant molecular farming to meet the industrial manufacturing and clinical application standards. In this review, we discuss the technological advances made in various plant expression platforms, with special focus on the upstream designs and milestone achievements in improving the yield and glycosylation of the plant-produced pharmaceutical proteins.
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89
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Gupta K, Rishishwar R, Dasgupta I. The interplay of plant hormonal pathways and geminiviral proteins: partners in disease development. Virus Genes 2022; 58:1-14. [PMID: 35034268 DOI: 10.1007/s11262-021-01881-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 11/28/2021] [Indexed: 10/19/2022]
Abstract
Viruses belonging to the family Geminiviridae infect plants and are responsible for a number of diseases of crops in the tropical and sub-tropical regions of the World. The innate immune response of the plant assists in its defense against such viral pathogens by the recognition of pathogen/microbe-associated molecular patterns through pattern-recognition receptors. Phytohormone signalling pathways play a vital role in plant defense responses against these devastating viruses. Geminiviruses, however, have developed counter-defense strategies that prevail over the above defense pathways. The proteins encoded by geminiviruses act as suppressors of plant immunity by interacting with the signalling components of several hormones. In this review we focus on the molecular interplay of phytohormone pathways and geminiviral infection and try to find interesting parallels with similar mechanisms known in other plant-infecting viruses and strengthen the argument that this interplay is necessary for disease development.
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Affiliation(s)
- Kanika Gupta
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, -110021, India
| | - Rashmi Rishishwar
- Department of Botany, Bhagat Singh Government P.G. College, Jaora, Ratlam, Madhya Pradesh, 457226, India
| | - Indranil Dasgupta
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, -110021, India.
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90
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Valmonte-Cortes GR, Lilly ST, Pearson MN, Higgins CM, MacDiarmid RM. The Potential of Molecular Indicators of Plant Virus Infection: Are Plants Able to Tell Us They Are Infected? PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11020188. [PMID: 35050076 PMCID: PMC8777591 DOI: 10.3390/plants11020188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/21/2021] [Accepted: 01/06/2022] [Indexed: 05/06/2023]
Abstract
To our knowledge, there are no reports that demonstrate the use of host molecular markers for the purpose of detecting generic plant virus infection. Two approaches involving molecular indicators of virus infection in the model plant Arabidopsis thaliana were examined: the accumulation of small RNAs (sRNAs) using a microfluidics-based method (Bioanalyzer); and the transcript accumulation of virus-response related host plant genes, suppressor of gene silencing 3 (AtSGS3) and calcium-dependent protein kinase 3 (AtCPK3) by reverse transcriptase-quantitative PCR (RT-qPCR). The microfluidics approach using sRNA chips has previously demonstrated good linearity and good reproducibility, both within and between chips. Good limits of detection have been demonstrated from two-fold 10-point serial dilution regression to 0.1 ng of RNA. The ratio of small RNA (sRNA) to ribosomal RNA (rRNA), as a proportion of averaged mock-inoculation, correlated with known virus infection to a high degree of certainty. AtSGS3 transcript decreased between 14- and 28-days post inoculation (dpi) for all viruses investigated, while AtCPK3 transcript increased between 14 and 28 dpi for all viruses. A combination of these two molecular approaches may be useful for assessment of virus-infection of samples without the need for diagnosis of specific virus infection.
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Affiliation(s)
- Gardette R. Valmonte-Cortes
- School of Science, AUT City Campus, Auckland University of Technology, Auckland 1142, New Zealand;
- The New Zealand Institute for Plant & Food Research Limited, 120 Mt Albert Road, Auckland 1025, New Zealand; (S.T.L.); (R.M.M.)
- Correspondence:
| | - Sonia T. Lilly
- The New Zealand Institute for Plant & Food Research Limited, 120 Mt Albert Road, Auckland 1025, New Zealand; (S.T.L.); (R.M.M.)
- School of Biological Sciences, The University of Auckland, Thomas Building, 3a Symonds Street, Auckland 1010, New Zealand;
| | - Michael N. Pearson
- School of Biological Sciences, The University of Auckland, Thomas Building, 3a Symonds Street, Auckland 1010, New Zealand;
| | - Colleen M. Higgins
- School of Science, AUT City Campus, Auckland University of Technology, Auckland 1142, New Zealand;
| | - Robin M. MacDiarmid
- The New Zealand Institute for Plant & Food Research Limited, 120 Mt Albert Road, Auckland 1025, New Zealand; (S.T.L.); (R.M.M.)
- School of Biological Sciences, The University of Auckland, Thomas Building, 3a Symonds Street, Auckland 1010, New Zealand;
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91
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Li F, Wang A. Transient Expression-Mediated Gene Silencing in Plants and Suppression of Gene Silencing with Viral Suppressors. Methods Mol Biol 2022; 2400:33-41. [PMID: 34905188 DOI: 10.1007/978-1-0716-1835-6_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Posttranscriptional gene silencing (PTGS) also known as RNA silencing or RNA interference is an evolutionarily conserved innate immunity in eukaryotes that targets the complementary RNA sequences to slice/degrade the target RNA or repress the translation of mRNA. In the past two decades, RNA silencing as an important antiviral mechanism has been studied extensively in plants. Intriguingly, almost every virus encodes at least a viral suppressor of RNA silencing (VSR) to counterattack RNA silencing with many strategies to interfere with different steps of RNA silencing. Therefore, the molecular identification of VSRs and elucidation of their functional mechanisms contribute to a better understanding of host resistance and viral pathogenicity. Here, we describe a protocol for the transient expression-induced gene silencing in 16c GFP transgenic and wild type Nicotiana benthamiana plants, and the suppression of single-stranded GFP and double-stranded GFP induced RNA silencing with a VSR in N. benthamiana plants. This protocol is simple and can serve as a standard for the identification and functional analysis of a VSR.
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Affiliation(s)
- Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
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92
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Marttinen EM, Lehtonen MT, van Gessel N, Reski R, Valkonen JPT. Viral suppressor of RNA silencing in vascular plants also interferes with the development of the bryophyte Physcomitrella patens. PLANT, CELL & ENVIRONMENT 2022; 45:220-235. [PMID: 34564869 PMCID: PMC9135061 DOI: 10.1111/pce.14194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Plant viruses are important pathogens able to overcome plant defense mechanisms using their viral suppressors of RNA silencing (VSR). Small RNA pathways of bryophytes and vascular plants have significant similarities, but little is known about how viruses interact with mosses. This study elucidated the responses of Physcomitrella patens to two different VSRs. We transformed P. patens plants to express VSR P19 from tomato bushy stunt virus and VSR 2b from cucumber mosaic virus, respectively. RNA sequencing and quantitative PCR were used to detect the effects of VSRs on gene expression. Small RNA (sRNA) sequencing was used to estimate the influences of VSRs on the sRNA pool of P. patens. Expression of either VSR-encoding gene caused developmental disorders in P. patens. The transcripts of four different transcription factors (AP2/erf, EREB-11 and two MYBs) accumulated in the P19 lines. sRNA sequencing revealed that VSR P19 significantly changed the microRNA pool in P. patens. Our results suggest that VSR P19 is functional in P. patens and affects the abundance of specific microRNAs interfering with gene expression. The results open new opportunities for using Physcomitrella as an alternative system to study plant-virus interactions.
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Affiliation(s)
- Eeva M. Marttinen
- Department of Agricultural SciencesUniversity of HelsinkiHelsinkiFinland
| | - Mikko T. Lehtonen
- Department of Agricultural SciencesUniversity of HelsinkiHelsinkiFinland
- Plant Analytics UnitFinnish Food AuthorityHelsinkiFinland
| | - Nico van Gessel
- Plant Biotechnology, Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Ralf Reski
- Plant Biotechnology, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Signalling Research Centres BIOSS and CIBSSUniversity of FreiburgFreiburgGermany
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93
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Pasin F, Daròs JA, Tzanetakis IE. OUP accepted manuscript. FEMS Microbiol Rev 2022; 46:6534904. [PMID: 35195244 PMCID: PMC9249622 DOI: 10.1093/femsre/fuac011] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 02/02/2022] [Accepted: 02/08/2022] [Indexed: 11/17/2022] Open
Abstract
Potyviridae, the largest family of known RNA viruses (realm Riboviria), belongs to the picorna-like supergroup and has important agricultural and ecological impacts. Potyvirid genomes are translated into polyproteins, which are in turn hydrolyzed to release mature products. Recent sequencing efforts revealed an unprecedented number of potyvirids with a rich variability in gene content and genomic layouts. Here, we review the heterogeneity of non-core modules that expand the structural and functional diversity of the potyvirid proteomes. We provide a family-wide classification of P1 proteinases into the functional Types A and B, and discuss pretty interesting sweet potato potyviral ORF (PISPO), putative zinc fingers, and alkylation B (AlkB)—non-core modules found within P1 cistrons. The atypical inosine triphosphate pyrophosphatase (ITPase/HAM1), as well as the pseudo tobacco mosaic virus-like coat protein (TMV-like CP) are discussed alongside homologs of unrelated virus taxa. Family-wide abundance of the multitasking helper component proteinase (HC-pro) is revised. Functional connections between non-core modules are highlighted to support host niche adaptation and immune evasion as main drivers of the Potyviridae evolutionary radiation. Potential biotechnological and synthetic biology applications of potyvirid leader proteinases and non-core modules are finally explored.
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Affiliation(s)
- Fabio Pasin
- Corresponding author: Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València (CSIC-UPV), UPV Building 8E, Ingeniero Fausto Elio, 46011 Valencia, Spain. E-mail:
| | - José-Antonio Daròs
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València (CSIC-UPV), 46011 Valencia, Spain
| | - Ioannis E Tzanetakis
- Department of Entomology and Plant Pathology, Division of Agriculture, University of Arkansas System, 72701 Fayetteville, AR, USA
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94
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Narayan A, Zahra S, Singh A, Kumar S. In Silico Methods for the Identification of Viral-Derived Small Interfering RNAs (vsiRNAs) and Their Application in Plant Genomics. Methods Mol Biol 2022; 2408:71-84. [PMID: 35325416 DOI: 10.1007/978-1-0716-1875-2_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The current era of high-throughput sequencing (HTS) technology has expedited the detection and diagnosis of viruses and viroids in the living system including plants. HTS data has become vital to study the etiology of the infection caused by both known as well as novel viral elements in planta, and their impact on overall crop health and productivity. Viral-derived small interfering RNAs are generated as a result of defence response by the host via RNAi machinery. They are immensely exploited for performing exhaustive viral investigations in plants using bioinformatics as well as experimental approaches.This chapter briefly presents the basics of virus-derived small interfering RNAs (vsiRNAs ) biology in plants and their applications in plant genomics and highlights in silico strategies exploited for virus/viroid detection. It gives a systematic pipeline for vsiRNAs identification using currently available bioinformatics tools and databases. This will surely work as a quick beginner's recipe for the in silico revelation of plant vsiRNAs as well as virus/viroid diagnosis using high-throughput sequencing data.
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Affiliation(s)
| | - Shafaque Zahra
- Bioinformatics Laboratory, National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi, India
| | - Ajeet Singh
- Bioinformatics Laboratory, National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi, India
| | - Shailesh Kumar
- Bioinformatics Laboratory, National Institute of Plant Genome Research (NIPGR), Aruna Asaf Ali Marg, New Delhi, India.
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95
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Pantaleo V, Masuta C. Diversity of viral RNA silencing suppressors and their involvement in virus-specific symptoms. Adv Virus Res 2022; 113:1-23. [DOI: 10.1016/bs.aivir.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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96
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Kuepper A, McLoughlin NM, Neubacher S, Yeste-Vázquez A, Collado Camps E, Nithin C, Mukherjee S, Bethge L, Bujnicki JM, Brock R, Heinrichs S, Grossmann TN. Constrained peptides mimic a viral suppressor of RNA silencing. Nucleic Acids Res 2021; 49:12622-12633. [PMID: 34871435 PMCID: PMC8682738 DOI: 10.1093/nar/gkab1149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 10/01/2021] [Accepted: 11/03/2021] [Indexed: 12/26/2022] Open
Abstract
The design of high-affinity, RNA-binding ligands has proven very challenging. This is due to the unique structural properties of RNA, often characterized by polar surfaces and high flexibility. In addition, the frequent lack of well-defined binding pockets complicates the development of small molecule binders. This has triggered the search for alternative scaffolds of intermediate size. Among these, peptide-derived molecules represent appealing entities as they can mimic structural features also present in RNA-binding proteins. However, the application of peptidic RNA-targeting ligands is hampered by a lack of design principles and their inherently low bio-stability. Here, the structure-based design of constrained α-helical peptides derived from the viral suppressor of RNA silencing, TAV2b, is described. We observe that the introduction of two inter-side chain crosslinks provides peptides with increased α-helicity and protease stability. One of these modified peptides (B3) shows high affinity for double-stranded RNA structures including a palindromic siRNA as well as microRNA-21 and its precursor pre-miR-21. Notably, B3 binding to pre-miR-21 inhibits Dicer processing in a biochemical assay. As a further characteristic this peptide also exhibits cellular entry. Our findings show that constrained peptides can efficiently mimic RNA-binding proteins rendering them potentially useful for the design of bioactive RNA-targeting ligands.
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Affiliation(s)
- Arne Kuepper
- Chemical Genomics Centre of the Max Planck Society, Dortmund 44227, Germany
- Department of Chemistry and Chemical Biology, Technical University Dortmund, Dortmund 44227, Germany
| | - Niall M McLoughlin
- Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
| | - Saskia Neubacher
- Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
| | - Alejandro Yeste-Vázquez
- Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
| | - Estel Collado Camps
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen Medical Center, Nijmegen 6525 GA, The Netherlands
| | - Chandran Nithin
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw 02-109, Poland
| | - Sunandan Mukherjee
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw 02-109, Poland
| | - Lucas Bethge
- Silence Therapeutics GmbH, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | - Janusz M Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, Warsaw 02-109, Poland
| | - Roland Brock
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen Medical Center, Nijmegen 6525 GA, The Netherlands
- Department of Medical Biochemistry, College of Medicine and Medical Sciences, Arabian Gulf University, Manama 293, Bahrain
| | - Stefan Heinrichs
- University Hospital Essen, Institute for Transfusion Medicine, Essen 45147, Germany
| | - Tom N Grossmann
- Chemical Genomics Centre of the Max Planck Society, Dortmund 44227, Germany
- Department of Chemistry and Chemical Biology, Technical University Dortmund, Dortmund 44227, Germany
- Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, Amsterdam 1081 HZ, The Netherlands
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97
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Dalmadi Á, Miloro F, Bálint J, Várallyay É, Havelda Z. Controlled RISC loading efficiency of miR168 defined by miRNA duplex structure adjusts ARGONAUTE1 homeostasis. Nucleic Acids Res 2021; 49:12912-12928. [PMID: 34850097 PMCID: PMC8682782 DOI: 10.1093/nar/gkab1138] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 10/25/2021] [Accepted: 11/16/2021] [Indexed: 11/12/2022] Open
Abstract
Micro RNAs (miRNAs) are processed from precursor RNA molecules with precisely defined secondary stem-loop structures. ARGONAUTE1 (AGO1) is the main executor component of miRNA pathway and its expression is controlled via the auto-regulatory feedback loop activity of miR168 in plants. Previously we have shown that AGO1 loading of miR168 is strongly restricted leading to abundant cytoplasmic accumulation of AGO-unbound miR168. Here, we report, that intrinsic RNA secondary structure of MIR168a precursor not only defines the processing of miR168, but also precisely adjusts AGO1 loading efficiency determining the biologically active subset of miR168 pool. Our results show, that modification of miRNA duplex structure of MIR168a precursor fragment or expression from artificial precursors can alter the finely adjusted loading efficiency of miR168. In dcl1-9 mutant where, except for miR168, production of most miRNAs is severely reduced this mechanism ensures the elimination of unloaded AGO1 proteins via enhanced AGO1 loading of miR168. Based on this data, we propose a new competitive loading mechanism model for miR168 action: the miR168 surplus functions as a molecular buffer for controlled AGO1 loading continuously adjusting the amount of AGO1 protein in accordance with the changing size of the cellular miRNA pool.
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Affiliation(s)
- Ágnes Dalmadi
- Hungarian University of Agriculture and Life Sciences, Institute of Genetics and Biotechnology, Páter Károly Street 1, Gödöllő 2100, Hungary
| | - Fabio Miloro
- Hungarian University of Agriculture and Life Sciences, Institute of Genetics and Biotechnology, Páter Károly Street 1, Gödöllő 2100, Hungary
| | - Jeannette Bálint
- National Agricultural Research and Innovation Centre, Agricultural Biotechnology Institute, Szent-Györgyi Albert Street 4, Gödöllő 2100, Hungary
| | - Éva Várallyay
- Hungarian University of Agriculture and Life Sciences, Institute of Plant Protection, Ménesi Street 44, Budapest 1118, Hungary
| | - Zoltán Havelda
- To whom correspondence should be addressed. Tel: +36 28430494;
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98
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Annacondia ML, Martinez G. Reprogramming of RNA silencing triggered by cucumber mosaic virus infection in Arabidopsis. Genome Biol 2021; 22:340. [PMID: 34911561 PMCID: PMC8672585 DOI: 10.1186/s13059-021-02564-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 12/02/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND RNA silencing has an important role mediating sequence-specific virus resistance in plants. The complex interaction of viruses with RNA silencing involves the loading of viral small interfering RNAs (vsiRNAs) into its host ARGONAUTE (AGO) proteins. As a side effect of their antiviral activity, vsiRNAs loading into AGO proteins can also mediate the silencing of endogenous genes. Here, we analyze at the genome-wide level both aspects of the interference of cucumber mosaic virus (CMV) with the RNA silencing machinery of Arabidopsis thaliana. RESULTS We observe CMV-derived vsiRNAs affect the levels of endogenous sRNA classes. Furthermore, we analyze the incorporation of vsiRNAs into AGO proteins with a described antiviral role and the viral suppressor of RNA silencing (VSR) 2b, by combining protein immunoprecipitation with sRNA high-throughput sequencing. Interestingly, vsiRNAs represent a substantial percentage of AGO-loaded sRNAs and displace other endogenous sRNAs. As a countermeasure, the VSR 2b loaded vsiRNAs and mRNA-derived siRNAs, which affect the expression of the genes they derive from. Additionally, we analyze how vsiRNAs incorporate into the endogenous RNA silencing pathways by exploring their target mRNAs using parallel analysis of RNA end (PARE) sequencing, which allow us to identify vsiRNA-targeted genes genome-wide. CONCLUSIONS This work exemplifies the complex relationship of RNA viruses with the endogenous RNA silencing machinery and the multiple aspects of virus resistance and virulence that this interaction induces.
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Affiliation(s)
- Maria Luz Annacondia
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - German Martinez
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden.
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99
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García B, Bedoya L, García JA, Rodamilans B. An Importin-β-like Protein from Nicotiana benthamiana Interacts with the RNA Silencing Suppressor P1b of the Cucumber Vein Yellowing Virus, Modulating Its Activity. Viruses 2021; 13:2406. [PMID: 34960675 PMCID: PMC8706682 DOI: 10.3390/v13122406] [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: 11/11/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 11/26/2022] Open
Abstract
During a plant viral infection, host-pathogen interactions are critical for successful replication and propagation of the virus through the plant. RNA silencing suppressors (RSSs) are key players of this interplay, and they often interact with different host proteins, developing multiple functions. In the Potyviridae family, viruses produce two main RSSs, HCPro and type B P1 proteins. We focused our efforts on the less known P1b of cucumber vein yellowing virus (CVYV), a type B P1 protein, to try to identify possible factors that could play a relevant role during viral infection. We used a chimeric expression system based on plum pox virus (PPV) encoding a tagged CVYV P1b in place of the canonical HCPro. We used that tag to purify P1b in Nicotiana-benthamiana-infected plants and identified by mass spectrometry an importin-β-like protein similar to importin 7 of Arabidopsis thaliana. We further confirmed the interaction by bimolecular fluorescence complementation assays and defined its nuclear localization in the cell. Further analyses showed a possible role of this N. benthamiana homolog of Importin 7 as a modulator of the RNA silencing suppression activity of P1b.
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Affiliation(s)
| | | | | | - Bernardo Rodamilans
- Centro Nacional de Biotecnología CNB, Consejo Superior de Investigaciones Científicas CSIC, 28049 Madrid, Spain; (B.G.); (L.B.); (J.A.G.)
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100
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Gao Y, Yang J, Zhang X, Chen A, Gu Z, Du Z. The Weak Small RNA-Binding Activity of the 2b Proteins of Subgroup II Cucumber Mosaic Virus Strains Is Insufficient for RNA Silencing Suppression. Front Microbiol 2021; 12:760937. [PMID: 34745069 PMCID: PMC8569468 DOI: 10.3389/fmicb.2021.760937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/15/2021] [Indexed: 11/13/2022] Open
Abstract
The 2b proteins encoded by cucumber mosaic virus (CMV) subgroup I strains suppress RNA silencing primarily by competitively binding small RNAs (sRNAs) in the host cell cytoplasm. Interestingly, 2b proteins encoded by CMV subgroup II strains accumulate predominantly in nuclei. Here we determined that whereas the 2b protein (Fny2b) of subgroup IA strain Fny-CMV is highly effective in suppressing both sense RNA-induced and inverted repeat-induced posttranscriptional gene silencing, the 2b protein (LS2b) of the subgroup II strain LS-CMV was not as effective. Reducing nuclear accumulation of LS2b by mutating a residue in its nuclear localization sequence had no effect on RNA silencing suppressor activity, while attenuated viral symptoms. Electrophoretic mobility shift assays showed that the sRNA binding of LS2b was weaker and more selective than that of Fny2b. The domain determining the differential sRNA-binding ability was delimited to the putative helix α1 region. Moreover, LS2b mutants that completely lost suppressor activity still retained their weak sRNA-binding ability, suggesting that sRNA binding is not sufficient for LS2b to suppress RNA silencing. Considering the subgroup I strain-encoded 2b proteins that require sRNA-binding ability for the suppression of RNA silencing, we suggest that in addition to binding sRNA, the 2b proteins of subgroup II CMV strains would require extra biological activities to achieve RNA silencing inhibition.
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Affiliation(s)
- Yingying Gao
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Jinrui Yang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Xiaobei Zhang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Aizhong Chen
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Zhouhang Gu
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Zhiyou Du
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
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