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Carrasco JL, Ambrós S, Gutiérrez PA, Elena SF. Adaptation of turnip mosaic virus to Arabidopsis thaliana involves rewiring of VPg-host proteome interactions. Virus Evol 2024; 10:veae055. [PMID: 39091990 PMCID: PMC11291303 DOI: 10.1093/ve/veae055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 05/23/2024] [Accepted: 07/16/2024] [Indexed: 08/04/2024] Open
Abstract
The outcome of a viral infection depends on a complex interplay between the host physiology and the virus, mediated through numerous protein-protein interactions. In a previous study, we used high-throughput yeast two-hybrid (HT-Y2H) to identify proteins in Arabidopsis thaliana that bind to the proteins encoded by the turnip mosaic virus (TuMV) genome. Furthermore, after experimental evolution of TuMV lineages in plants with mutations in defense-related or proviral genes, most mutations observed in the evolved viruses affected the VPg cistron. Among these mutations, D113G was a convergent mutation selected in many lineages across different plant genotypes, including cpr5-2 with constitutive expression of systemic acquired resistance. In contrast, mutation R118H specifically emerged in the jin1 mutant with affected jasmonate signaling. Using the HT-Y2H system, we analyzed the impact of these two mutations on VPg's interaction with plant proteins. Interestingly, both mutations severely compromised the interaction of VPg with the translation initiation factor eIF(iso)4E, a crucial interactor for potyvirus infection. Moreover, mutation D113G, but not R118H, adversely affected the interaction with RHD1, a zinc-finger homeodomain transcription factor involved in regulating DNA demethylation. Our results suggest that RHD1 enhances plant tolerance to TuMV infection. We also discuss our findings in a broad virus evolution context.
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Affiliation(s)
- José L Carrasco
- Instituto de Biología Integrativa de Sistemas (CSIC—Universitat de València), Catedratico Agustin Escardino 9, Paterna, València 46182, Spain
| | - Silvia Ambrós
- Instituto de Biología Integrativa de Sistemas (CSIC—Universitat de València), Catedratico Agustin Escardino 9, Paterna, València 46182, Spain
| | - Pablo A Gutiérrez
- Laboratorio de Microbiología Industrial, Facultad de Ciencias, Universidad Nacional de Colombia, Carrera 65 Nro. 59A - 110, Medellín, Antioquia 050034, Colombia
| | - Santiago F Elena
- Instituto de Biología Integrativa de Sistemas (CSIC—Universitat de València), Catedratico Agustin Escardino 9, Paterna, València 46182, Spain
- The Santa Fe Institute, 1399 Hyde Park Rd, Santa Fe, NM 87501, United States
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2
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Mishina K, Kai H, Hamada M, Haraguchi Y, Oono Y, Ordon F, Komatsuda T. Series of Resistance Genes in Barley ( Hordeum vulgare) that Control Barley Yellow Mosaic Virus Multiplication and the Root-to-Leaf Systemic Movement. PLANT DISEASE 2024; 108:1719-1728. [PMID: 38173257 DOI: 10.1094/pdis-07-23-1451-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
The infection of young winter barley (Hordeum vulgare L.) root system in winter by barley yellow mosaic virus (BaYMV) can lead to high yield losses. Resistance breeding is critical for managing this virus, but there are only a few reports on resistance genes that describe how the genes control BaYMV propagation and the systemic movement from the roots to the leaves. Here we report a real-time quantitative PCR analysis of the virus in barley roots and leaves carrying BaYMV resistance genes (rym1 to rym15 and an unknown gene) to elucidate the molecular mechanisms underlying the barley response to BaYMV. The resistance mechanism directly targets the virus. Moreover, the resistance genes/cultivars were classified into the following three groups according to their BaYMV titer: (i) immune (BaYMV was undetectable in the roots or leaves), (ii) partially immune (BaYMV was detected in the roots but not in the leaves), and (iii) susceptible (BaYMV was detected in the roots and leaves). Our results clarified the functions of the resistance genes in barley roots and leaves following a BaYMV infection. We anticipate our analysis to be a starting point for more understanding of the correspondence between resistance genes of Triticeae and the soil-borne viruses.
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Affiliation(s)
- Kohei Mishina
- National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8602, Japan
| | - Hiroomi Kai
- Fukuoka Agricultural Research Center, Chikushino, Fukuoka 818-8577, Japan
| | - Michio Hamada
- Fukuoka Agricultural Research Center, Chikushino, Fukuoka 818-8577, Japan
| | - Yuhi Haraguchi
- Fukuoka Agricultural Research Center, Chikushino, Fukuoka 818-8577, Japan
| | - Youko Oono
- National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8602, Japan
| | - Frank Ordon
- Institute for Resistance Research and Stress Tolerance, Julius Kühn-Institute, Quedlinburg, Germany
| | - Takao Komatsuda
- National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8602, Japan
- Crop Research Institute, Shandong Academy of Agricultural Sciences (SAAS), Ji'nan, 250100 Shandong, China
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3
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Zhu H, Okiyama T, Mishina K, Kikuchi S, Sassa H, Komatsuda T, Kato T, Oono Y. Identification of Barley yellow mosaic virus Isolates Breaking rym3 Resistance in Japan. Genes (Basel) 2024; 15:697. [PMID: 38927633 PMCID: PMC11203024 DOI: 10.3390/genes15060697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 05/17/2024] [Accepted: 05/23/2024] [Indexed: 06/28/2024] Open
Abstract
In early spring 2018, significant mosaic disease symptoms were observed for the first time on barley leaves (Hordeum vulgare L., cv. New Sachiho Golden) in Takanezawa, Tochigi Prefecture, Japan. This cultivar carries the resistance gene rym3 (rym; resistance to yellow mosaic). Through RNA-seq analysis, Barley yellow mosaic virus (BaYMV-Takanezawa) was identified in the roots of all five plants (T01-T05) in the field. Phylogenetic analysis of RNA1, encompassing known BaYMV pathotypes I through V, revealed that it shares the same origin as isolate pathotype IV (BaYMV-Ohtawara pathotype). However, RNA2 analysis of isolates revealed the simultaneous presence of two distinct BaYMV isolates, BaYMV-Takanezawa-T01 (DRR552862, closely related to pathotype IV) and BaYMV-Takanezawa-T02 (DRR552863, closely related to pathotype III). The amino acid sequences of the BaYMV-Takanezawa isolates displayed variations, particularly in the VPg and N-terminal region of CP, containing mutations not found in other domains of the virus genome. Changes in the CI (RNA1 amino acid residue 459) and CP (RNA1 amino acid residue 2138) proteins correlated with pathogenicity. These findings underscore the importance of monitoring and understanding the genetic diversity of BaYMV for effective disease management strategies in crop breeding.
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Affiliation(s)
- Hongjing Zhu
- Institute of Crop Science, National Agriculture and Food Research Organization (NARO), 2-1-2 Kannondai, Tsukuba 305-8602, Japan; (H.Z.); (K.M.)
- Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo 271-8510, Japan; (S.K.); (H.S.)
| | - Takeshi Okiyama
- Tochigi Prefectural Agricultural Experiment Station, Kawaraya-cho 1080, Utsunomiya 320-0002, Japan; (T.O.); (T.K.)
| | - Kohei Mishina
- Institute of Crop Science, National Agriculture and Food Research Organization (NARO), 2-1-2 Kannondai, Tsukuba 305-8602, Japan; (H.Z.); (K.M.)
| | - Shinji Kikuchi
- Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo 271-8510, Japan; (S.K.); (H.S.)
| | - Hidenori Sassa
- Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo 271-8510, Japan; (S.K.); (H.S.)
| | - Takao Komatsuda
- Shandong Academy of Agricultural Sciences (SAAS), Crop Research Institute, 202 Gongyebei Road, Licheng District, Jinan 250100, China;
| | - Tsuneo Kato
- Tochigi Prefectural Agricultural Experiment Station, Kawaraya-cho 1080, Utsunomiya 320-0002, Japan; (T.O.); (T.K.)
| | - Youko Oono
- Institute of Crop Science, National Agriculture and Food Research Organization (NARO), 2-1-2 Kannondai, Tsukuba 305-8602, Japan; (H.Z.); (K.M.)
- Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo 271-8510, Japan; (S.K.); (H.S.)
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4
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Khan MA, Yumak S, Miyoshi H. Poly(A)-binding protein promotes VPg-dependent translation of potyvirus through enhanced binding of phosphorylated eIFiso4F and eIFiso4F∙eIF4B. PLoS One 2024; 19:e0300287. [PMID: 38696388 PMCID: PMC11065315 DOI: 10.1371/journal.pone.0300287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 02/24/2024] [Indexed: 05/04/2024] Open
Abstract
The phosphorylation of eukaryotic translational initiation factors has been shown to play a significant role in controlling the synthesis of protein. Viral infection, environmental stress, and growth circumstances cause phosphorylation or dephosphorylation of plant initiation factors. Our findings indicate that casein kinase 2 can phosphorylate recombinant wheat eIFiso4E and eIFiso4G generated from E. coli in vitro. For wheat eIFiso4E, Ser-207 was found to be the in vitro phosphorylation site. eIFiso4E lacks an amino acid that can be phosphorylated at the position corresponding to Ser-209, the phosphorylation site in mammalian eIF4E, yet phosphorylation of eIFiso4E has effects on VPg binding affinity that are similar to those of phosphorylation of mammalian eIF4E. The addition of VPg and phosphorylated eIFiso4F to depleted wheat germ extract (WGE) leads to enhancement of translation of both uncapped and capped viral mRNA. The addition of PABP together with eIFiso4Fp and eIF4B to depleted WGE increases both uncapped and capped mRNA translation. However, it exhibits a translational advantage specifically for uncapped mRNA, implying that the phosphorylation of eIFiso4F hinders cap binding while promoting VPg binding, thereby facilitating uncapped translation. These findings indicate TEV virus mediates VPg-dependent translation by engaging a mechanism entailing phosphorylated eIFiso4Fp and PABP. To elucidate the molecular mechanisms underlying these observed effects, we studied the impact of PABP and/or eIF4B on the binding of VPg with eIFiso4Fp. The inclusion of PABP and eIF4B with eIFiso4Fp resulted in about 2-fold increase in affinity for VPg (Kd = 24 ± 1.7 nM), as compared to the affinity of eIFiso4Fp alone (Kd = 41.0 ± 3.1 nM). The interactions between VPg and eIFiso4Fp were determined to be both enthalpically and entropically favorable, with the enthalpic contribution accounting for 76-97% of the ΔG at 25°C, indicating a substantial role of hydrogen bonding in enhancing the stability of the complex. The binding of PABP to eIFiso4Fp·4B resulted in a conformational alteration, leading to a significant enhancement in the binding affinity to VPg. These observations suggest PABP enhances the affinity between eIFiso4Fp and VPg, leading to an overall conformational change that provides a stable platform for efficient viral translation.
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Affiliation(s)
- Mateen A. Khan
- Department of Life Sciences, College of Science and General Studies, Alfaisal University Riyadh, Riyadh, Saudi Arabia
| | - Sumeyra Yumak
- Department of Science, Borough of Manhattan Community College, City University of New York, New York, NY, United States of America
| | - Hiroshi Miyoshi
- Department of Microbiology, St. Marianna University School of Medicine, Kawasaki, Japan
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5
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Dutta P, Mäkinen K. Absolute and Relative Quantification of Single-Stranded Positive-Sense RNA Viruses from Plant Tissue. Methods Mol Biol 2024; 2724:81-91. [PMID: 37987900 DOI: 10.1007/978-1-0716-3485-1_7] [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: 11/22/2023]
Abstract
Reverse transcription quantitative PCR (RT-qPCR) allows sensitive and specific measurement of mRNA transcripts from a given sample in a short period of time. Relative and absolute RT-qPCR are two strategies that could be used to quantify mRNA transcripts, based on the goal of the experiment. Here, we describe the protocol for the quantification of plant viral RNA transcripts from an infected sample using both strategies.
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Affiliation(s)
- Pinky Dutta
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Kristiina Mäkinen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland.
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6
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Zafirov D, Giovinazzo N, Lecampion C, Field B, Ducassou JN, Couté Y, Browning KS, Robaglia C, Gallois JL. Arabidopsis eIF4E1 protects the translational machinery during TuMV infection and restricts virus accumulation. PLoS Pathog 2023; 19:e1011417. [PMID: 37983287 PMCID: PMC10721207 DOI: 10.1371/journal.ppat.1011417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 12/14/2023] [Accepted: 10/23/2023] [Indexed: 11/22/2023] Open
Abstract
Successful subversion of translation initiation factors eIF4E determines the infection success of potyviruses, the largest group of viruses affecting plants. In the natural variability of many plant species, resistance to potyvirus infection is provided by polymorphisms at eIF4E that renders them inadequate for virus hijacking but still functional in translation initiation. In crops where such natural resistance alleles are limited, the genetic inactivation of eIF4E has been proposed for the engineering of potyvirus resistance. However, recent findings indicate that knockout eIF4E alleles may be deleterious for plant health and could jeopardize resistance efficiency in comparison to functional resistance proteins. Here, we explored the cause of these adverse effects by studying the role of the Arabidopsis eIF4E1, whose inactivation was previously reported as conferring resistance to the potyvirus clover yellow vein virus (ClYVV) while also promoting susceptibility to another potyvirus turnip mosaic virus (TuMV). We report that eIF4E1 is required to maintain global plant translation and to restrict TuMV accumulation during infection, and its absence is associated with a favoured virus multiplication over host translation. Furthermore, our findings show that, in the absence of eIF4E1, infection with TuMV results in the production of a truncated eIFiso4G1 protein. Finally, we demonstrate a role for eIFiso4G1 in TuMV accumulation and in supporting plant fitness during infection. These findings suggest that eIF4E1 counteracts the hijacking of the plant translational apparatus during TuMV infection and underscore the importance of preserving the functionality of translation initiation factors eIF4E when implementing potyvirus resistance strategies.
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Affiliation(s)
- Delyan Zafirov
- GAFL, INRAE, Montfavet, France
- Aix-Marseille Univ, CEA, CNRS, BIAM, LGBP Team, Marseille, France
| | | | - Cécile Lecampion
- Aix-Marseille Univ, CEA, CNRS, BIAM, LGBP Team, Marseille, France
| | - Ben Field
- Aix-Marseille Univ, CEA, CNRS, BIAM, LGBP Team, Marseille, France
| | | | - Yohann Couté
- Univ. Grenoble Alpes, INSERM, CEA, UA13 BGE, CNRS, CEA, Grenoble, France
| | - Karen S. Browning
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas, United States of America
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7
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Chang Z, Wang X, Pan X, Yan W, Wu W, Zhuang Y, Li Z, Wang D, Yuan S, Xu C, Chen Z, Liu D, Chen ZS, Tang X, Wu J. The ribosomal protein P0A is required for embryo development in rice. BMC PLANT BIOLOGY 2023; 23:465. [PMID: 37798654 PMCID: PMC10552409 DOI: 10.1186/s12870-023-04445-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 09/06/2023] [Indexed: 10/07/2023]
Abstract
BACKGROUND The P-stalk is a conserved and vital structural element of ribosome. The eukaryotic P-stalk exists as a P0-(P1-P2)2 pentameric complex, in which P0 function as a base structure for incorporating the stalk onto 60S pre-ribosome. Prior studies have suggested that P0 genes are indispensable for survival in yeast and animals. However, the functions of P0 genes in plants remain elusive. RESULTS In the present study, we show that rice has three P0 genes predicted to encode highly conserved proteins OsP0A, OsP0B and OsP0C. All of these P0 proteins were localized both in cytoplasm and nucleus, and all interacted with OsP1. Intriguingly, the transcripts of OsP0A presented more than 90% of the total P0 transcripts. Moreover, knockout of OsP0A led to embryo lethality, while single or double knockout of OsP0B and OsP0C did not show any visible defects in rice. The genomic DNA of OsP0A could well complement the lethal phenotypes of osp0a mutant. Finally, sequence and syntenic analyses revealed that OsP0C evolved from OsP0A, and that duplication of genomic fragment harboring OsP0C further gave birth to OsP0B, and both of these duplication events might happen prior to the differentiation of indica and japonica subspecies in rice ancestor. CONCLUSION These data suggested that OsP0A functions as the predominant P0 gene, playing an essential role in embryo development in rice. Our findings highlighted the importance of P0 genes in plant development.
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Affiliation(s)
- Zhenyi Chang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Xia Wang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Xiaoying Pan
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Wei Yan
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Wenshi Wu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Yi Zhuang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Zhiai Li
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Dan Wang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Shuting Yuan
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Chunjue Xu
- Shenzhen Institute of Molecular Crop Design, Shenzhen, 518107, China
| | - Zhufeng Chen
- Shenzhen Institute of Molecular Crop Design, Shenzhen, 518107, China
| | - Dongfeng Liu
- Shenzhen Agricultural Technology Promotion Center, Shenzhen, 518055, China
| | - Zi Sheng Chen
- Shenzhen Agricultural Technology Promotion Center, Shenzhen, 518055, China.
| | - Xiaoyan Tang
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
- Shenzhen Institute of Molecular Crop Design, Shenzhen, 518107, China.
| | - Jianxin Wu
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
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8
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Mäkinen K, Aspelin W, Pollari M, Wang L. How do they do it? The infection biology of potyviruses. Adv Virus Res 2023; 117:1-79. [PMID: 37832990 DOI: 10.1016/bs.aivir.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2023]
Affiliation(s)
- Kristiina Mäkinen
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland.
| | - William Aspelin
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Maija Pollari
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Linping Wang
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
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9
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Atabekova AK, Solovieva AD, Chergintsev DA, Solovyev AG, Morozov SY. Role of Plant Virus Movement Proteins in Suppression of Host RNAi Defense. Int J Mol Sci 2023; 24:ijms24109049. [PMID: 37240394 DOI: 10.3390/ijms24109049] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 05/28/2023] Open
Abstract
One of the systems of plant defense against viral infection is RNA silencing, or RNA interference (RNAi), in which small RNAs derived from viral genomic RNAs and/or mRNAs serve as guides to target an Argonaute nuclease (AGO) to virus-specific RNAs. Complementary base pairing between the small interfering RNA incorporated into the AGO-based protein complex and viral RNA results in the target cleavage or translational repression. As a counter-defensive strategy, viruses have evolved to acquire viral silencing suppressors (VSRs) to inhibit the host plant RNAi pathway. Plant virus VSR proteins use multiple mechanisms to inhibit silencing. VSRs are often multifunctional proteins that perform additional functions in the virus infection cycle, particularly, cell-to-cell movement, genome encapsidation, or replication. This paper summarizes the available data on the proteins with dual VSR/movement protein activity used by plant viruses of nine orders to override the protective silencing response and reviews the different molecular mechanisms employed by these proteins to suppress RNAi.
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Affiliation(s)
- Anastasia K Atabekova
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
| | - Anna D Solovieva
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Denis A Chergintsev
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Andrey G Solovyev
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Sergey Y Morozov
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
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10
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Zlobin N, Taranov V. Plant eIF4E isoforms as factors of susceptibility and resistance to potyviruses. FRONTIERS IN PLANT SCIENCE 2023; 14:1041868. [PMID: 36844044 PMCID: PMC9950400 DOI: 10.3389/fpls.2023.1041868] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
Potyviruses are the largest group of plant-infecting RNA viruses that affect a wide range of crop plants. Plant resistance genes against potyviruses are often recessive and encode translation initiation factors eIF4E. The inability of potyviruses to use plant eIF4E factors leads to the development of resistance through a loss-of-susceptibility mechanism. Plants have a small family of eIF4E genes that encode several isoforms with distinct but overlapping functions in cell metabolism. Potyviruses use distinct eIF4E isoforms as susceptibility factors in different plants. The role of different members of the plant eIF4E family in the interaction with a given potyvirus could differ drastically. An interplay exists between different members of the eIF4E family in the context of plant-potyvirus interactions, allowing different eIF4E isoforms to modulate each other's availability as susceptibility factors for the virus. In this review, possible molecular mechanisms underlying this interaction are discussed, and approaches to identify the eIF4E isoform that plays a major role in the plant-potyvirus interaction are suggested. The final section of the review discusses how knowledge about the interaction between different eIF4E isoforms can be used to develop plants with durable resistance to potyviruses.
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11
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Jaramillo-Mesa H, Rakotondrafara AM. All eggs in one basket: How potyvirus infection is controlled at a single cap-independent translation event. Semin Cell Dev Biol 2023; 148-149:51-61. [PMID: 36608998 DOI: 10.1016/j.semcdb.2022.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/28/2022] [Accepted: 12/30/2022] [Indexed: 01/06/2023]
Abstract
Regulation of protein synthesis is a strong determinant of potyviral pathogenicity. The Potyviridae family is the largest family of plant-infecting positive sense RNA viruses. Similar to the animal-infecting Picornaviridae family, the potyviral RNA genome lacks a 5' cap, and instead has a viral protein (VPg) linked to its 5' end. Potyviral genomes are mainly translated into one large polyprotein relying on a single translation event to express all their protein repertoire. In the absence of the 5' cap, the Potyviridae family depends on cis-acting elements in their 5' untranslated regions (UTR) to recruit the translation machinery. In this review, we summarize the diverse 5'UTR-driven, cap-independent translation mechanisms employed by the Potyviridae family including scanning-dependent mechanism, internal initiation, and the stimulatory role of the VPg. These mechanisms have direct implications on potyviral pathogenicity, including host range specificity and resistance. Finally, we discuss how these viral strategies could not only inform new avenues for engineering and/or breeding for crop resistance but would also provide opportunities for the development of biotechnological tools for large-scale protein production in plant systems.
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Affiliation(s)
- Helena Jaramillo-Mesa
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53704, USA
| | - Aurélie M Rakotondrafara
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53704, USA.
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12
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Christie M, Igreja C. eIF4E-homologous protein (4EHP): a multifarious cap-binding protein. FEBS J 2023; 290:266-285. [PMID: 34758096 DOI: 10.1111/febs.16275] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/29/2021] [Accepted: 11/09/2021] [Indexed: 02/05/2023]
Abstract
The cap-binding protein 4EHP/eIF4E2 has been a recent object of interest in the field of post-transcriptional gene regulation and translational control. From ribosome-associated quality control, to RNA decay and microRNA-mediated gene silencing, this member of the eIF4E protein family regulates gene expression through numerous pathways. Low in abundance but ubiquitously expressed, 4EHP interacts with different binding partners to form multiple protein complexes that regulate translation in a variety of biological contexts. Documented functions of 4EHP primarily relate to its role as a translational repressor, but recent findings indicate that it might also participate in the activation of translation in specific settings. In this review, we discuss the known functions, properties and mechanisms that involve 4EHP in the control of gene expression. We also discuss our current understanding of how 4EHP processes are regulated in eukaryotic cells, and the diseases implicated with dysregulation of 4EHP-mediated translational control.
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Affiliation(s)
- Mary Christie
- School of Life and Environmental Sciences, The University of Sydney, NSW, Australia
| | - Cátia Igreja
- Department for Integrative Evolutionary Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany
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13
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Pollari M, Sipari N, Poque S, Himanen K, Mäkinen K. Effects of Poty-Potexvirus Synergism on Growth, Photosynthesis and Metabolite Status of Nicotiana benthamiana. Viruses 2022; 15:121. [PMID: 36680161 PMCID: PMC9867248 DOI: 10.3390/v15010121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/03/2023] Open
Abstract
Mixed virus infections threaten crop production because interactions between the host and the pathogen mix may lead to viral synergism. While individual infections by potato virus A (PVA), a potyvirus, and potato virus X (PVX), a potexvirus, can be mild, co-infection leads to synergistic enhancement of PVX and severe symptoms. We combined image-based phenotyping with metabolite analysis of single and mixed PVA and PVX infections and compared their effects on growth, photosynthesis, and metabolites in Nicotiana benthamiana. Viral synergism was evident in symptom severity and impaired growth in the plants. Indicative of stress, the co-infection increased leaf temperature and decreased photosynthetic parameters. In contrast, singly infected plants sustained photosynthetic activity. The host's metabolic response differed significantly between single and mixed infections. Over 200 metabolites were differentially regulated in the mixed infection: especially defense-related metabolites and aromatic and branched-chain amino acids increased compared to the control. Changes in the levels of methionine cycle intermediates and a low S-adenosylmethionine/S-adenosylhomocysteine ratio suggested a decline in the methylation potential in co-infected plants. The decreased ratio between reduced glutathione, an important scavenger of reactive oxygen species, and its oxidized form, indicated that severe oxidative stress developed during co-infection. Based on the results, infection-associated oxidative stress is successfully controlled in the single infections but not in the synergistic infection, where activated defense pathways are not sufficient to counter the impact of the infections on plant growth.
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Affiliation(s)
- Maija Pollari
- Department of Microbiology, Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland
| | - Nina Sipari
- Viikki Metabolomics Unit, Organismal and Evolutionary Biology Research Programme, Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland
| | - Sylvain Poque
- Department of Agricultural Sciences, Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland
| | - Kristiina Himanen
- National Plant Phenotyping Infrastructure, HiLIFE, Biocenter Finland, Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland
| | - Kristiina Mäkinen
- Department of Microbiology, Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland
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14
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Biswal AK, Alakonya AE, Mottaleb KA, Hearne SJ, Sonder K, Molnar TL, Jones AM, Pixley KV, Prasanna BM. Maize Lethal Necrosis disease: review of molecular and genetic resistance mechanisms, socio-economic impacts, and mitigation strategies in sub-Saharan Africa. BMC PLANT BIOLOGY 2022; 22:542. [PMID: 36418954 PMCID: PMC9686106 DOI: 10.1186/s12870-022-03932-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Maize lethal necrosis (MLN) disease is a significant constraint for maize producers in sub-Saharan Africa (SSA). The disease decimates the maize crop, in some cases, causing total crop failure with far-reaching impacts on regional food security. RESULTS In this review, we analyze the impacts of MLN in Africa, finding that resource-poor farmers and consumers are the most vulnerable populations. We examine the molecular mechanism of MLN virus transmission, role of vectors and host plant resistance identifying a range of potential opportunities for genetic and phytosanitary interventions to control MLN. We discuss the likely exacerbating effects of climate change on the MLN menace and describe a sobering example of negative genetic association between tolerance to heat/drought and susceptibility to viral infection. We also review role of microRNAs in host plant response to MLN causing viruses as well as heat/drought stress that can be carefully engineered to develop resistant varieties using novel molecular techniques. CONCLUSIONS With the dual drivers of increased crop loss due to MLN and increased demand of maize for food, the development and deployment of simple and safe technologies, like resistant cultivars developed through accelerated breeding or emerging gene editing technologies, will have substantial positive impact on livelihoods in the region. We have summarized the available genetic resources and identified a few large-effect QTLs that can be further exploited to accelerate conversion of existing farmer-preferred varieties into resistant cultivars.
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Affiliation(s)
- Akshaya Kumar Biswal
- International Maize and Wheat Improvement Center (CIMMYT), Km. 45, Carretera Mexico-Veracruz, El Batan, Texcoco, C.P. 56237, Mexico.
| | - Amos Emitati Alakonya
- International Maize and Wheat Improvement Center (CIMMYT), Km. 45, Carretera Mexico-Veracruz, El Batan, Texcoco, C.P. 56237, Mexico
| | - Khondokar Abdul Mottaleb
- International Maize and Wheat Improvement Center (CIMMYT), Km. 45, Carretera Mexico-Veracruz, El Batan, Texcoco, C.P. 56237, Mexico
| | - Sarah J Hearne
- International Maize and Wheat Improvement Center (CIMMYT), Km. 45, Carretera Mexico-Veracruz, El Batan, Texcoco, C.P. 56237, Mexico
| | - Kai Sonder
- International Maize and Wheat Improvement Center (CIMMYT), Km. 45, Carretera Mexico-Veracruz, El Batan, Texcoco, C.P. 56237, Mexico
| | | | - Alan M Jones
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Kevin Vail Pixley
- International Maize and Wheat Improvement Center (CIMMYT), Km. 45, Carretera Mexico-Veracruz, El Batan, Texcoco, C.P. 56237, Mexico
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15
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Zhang R, Zhang C, Lyu S, Wu H, Yuan M, Fang Z, Li F, Hou X. BcTFIIIA Negatively Regulates Turnip Mosaic Virus Infection through Interaction with Viral CP and VPg Proteins in Pak Choi (Brassica campestris ssp. chinensis). Genes (Basel) 2022; 13:genes13071209. [PMID: 35885992 PMCID: PMC9317785 DOI: 10.3390/genes13071209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/01/2022] [Accepted: 07/04/2022] [Indexed: 12/10/2022] Open
Abstract
TFIIIA is a zinc-finger transcription factor that is involved in post-transcriptional regulation during development. Here, the BcTFIIIA gene was isolated from pak choi. Sequence analysis showed that BcTFIIIA encodes 383 amino acids (aa) with an open reading frame (ORF) of 1152 base pairs (bp). We investigated the subcellular location of BcTFIIIA and found the localized protein in the nucleus. BcTFIIIA was suppressed when the pak choi was infected by the turnip mosaic virus (TuMV). The BcTFIIIA mRNA expression level in a resistant variety was higher than that in a sensitive variety, as determined by qRT-PCR analysis. Yeast two hybrid (Y2H) assay and bimolecular fluorescence complementation (BiFC) suggested that BcTFIIIA interacts with TuMV CP and VPg in vivo, respectively, and in vitro. A virus-induced gene silencing (VIGS) experiment showed that the silencing of BcTFIIIA gene expression in pak choi promoted the accumulation of TuMV. These results suggest that BcTFIIIA negatively regulates viral infection through the interaction with TuMV CP and VPg.
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Affiliation(s)
- Rujia Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China; (R.Z.); (C.Z.); (S.L.); (H.W.); (M.Y.)
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Nanjing Agricultural University, Nanjing 210095, China
| | - Changwei Zhang
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China; (R.Z.); (C.Z.); (S.L.); (H.W.); (M.Y.)
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Nanjing Agricultural University, Nanjing 210095, China
| | - Shanwu Lyu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China; (R.Z.); (C.Z.); (S.L.); (H.W.); (M.Y.)
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Nanjing Agricultural University, Nanjing 210095, China
| | - Huiyuan Wu
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China; (R.Z.); (C.Z.); (S.L.); (H.W.); (M.Y.)
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Nanjing Agricultural University, Nanjing 210095, China
| | - Mengguo Yuan
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China; (R.Z.); (C.Z.); (S.L.); (H.W.); (M.Y.)
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhiyuan Fang
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China;
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China;
| | - Xilin Hou
- State Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China; (R.Z.); (C.Z.); (S.L.); (H.W.); (M.Y.)
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (East China), Engineering Research Center of Germplasm Enhancement and Utilization of Horticultural Crops, Nanjing Agricultural University, Nanjing 210095, China
- Correspondence:
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Bera S, Arena GD, Ray S, Flannigan S, Casteel CL. The Potyviral Protein 6K1 Reduces Plant Proteases Activity during Turnip mosaic virus Infection. Viruses 2022; 14:1341. [PMID: 35746814 PMCID: PMC9229136 DOI: 10.3390/v14061341] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/30/2022] [Accepted: 06/12/2022] [Indexed: 12/25/2022] Open
Abstract
Potyviral genomes encode just 11 major proteins and multifunctionality is associated with most of these proteins at different stages of the virus infection cycle. Some potyviral proteins modulate phytohormones and protein degradation pathways and have either pro- or anti-viral/insect vector functions. Our previous work demonstrated that the potyviral protein 6K1 has an antagonistic effect on vectors when expressed transiently in host plants, suggesting plant defenses are regulated. However, to our knowledge the mechanisms of how 6K1 alters plant defenses and how 6K1 functions are regulated are still limited. Here we show that the 6K1 from Turnip mosaic virus (TuMV) reduces the abundance of transcripts related to jasmonic acid biosynthesis and cysteine protease inhibitors when expressed in Nicotiana benthamiana relative to controls. 6K1 stability increased when cysteine protease activity was inhibited chemically, showing a mechanism to the rapid turnover of 6K1 when expressed in trans. Using RNAseq, qRT-PCR, and enzymatic assays, we demonstrate TuMV reprograms plant protein degradation pathways on the transcriptional level and increases 6K1 stability at later stages in the infection process. Moreover, we show 6K1 decreases plant protease activity in infected plants and increases TuMV accumulation in systemic leaves compared to controls. These results suggest 6K1 has a pro-viral function in addition to the anti-insect vector function we observed previously. Although the host targets of 6K1 and the impacts of 6K1-induced changes in protease activity on insect vectors are still unknown, this study enhances our understanding of the complex interactions occurring between plants, potyviruses, and vectors.
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Affiliation(s)
- Sayanta Bera
- School of Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY 14850, USA; (S.B.); (S.R.); (S.F.)
| | - Gabriella D. Arena
- Laboratório de Biologia Molecular Aplicada, Instituto Biológico de São Paulo, São Paulo 04014-002, Brazil;
| | - Swayamjit Ray
- School of Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY 14850, USA; (S.B.); (S.R.); (S.F.)
| | - Sydney Flannigan
- School of Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY 14850, USA; (S.B.); (S.R.); (S.F.)
| | - Clare L. Casteel
- School of Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY 14850, USA; (S.B.); (S.R.); (S.F.)
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17
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Saha S, Lõhmus A, Dutta P, Pollari M, Mäkinen K. Interplay of HCPro and CP in the Regulation of Potato Virus A RNA Expression and Encapsidation. Viruses 2022; 14:1233. [PMID: 35746704 PMCID: PMC9227828 DOI: 10.3390/v14061233] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/27/2022] [Accepted: 06/03/2022] [Indexed: 12/04/2022] Open
Abstract
Potyviral coat protein (CP) and helper component-proteinase (HCPro) play key roles in both the regulation of viral gene expression and the formation of viral particles. We investigated the interplay between CP and HCPro during these viral processes. While the endogenous HCPro and a heterologous viral suppressor of gene silencing both complemented HCPro-less potato virus A (PVA) expression, CP stabilization connected to particle formation could be complemented only by the cognate PVA HCPro. We found that HCPro relieves CP-mediated inhibition of PVA RNA expression likely by enabling HCPro-mediated sequestration of CPs to particles. We addressed the question about the role of replication in formation of PVA particles and gained evidence for encapsidation of non-replicating PVA RNA. The extreme instability of these particles substantiates the need for replication in the formation of stable particles. During replication, viral protein genome linked (VPg) becomes covalently attached to PVA RNA and can attract HCPro, cylindrical inclusion protein and host proteins. Based on the results of the current study and our previous findings we propose a model in which a large ribonucleoprotein complex formed around VPg at one end of PVA particles is essential for their integrity.
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Affiliation(s)
| | | | | | | | - Kristiina Mäkinen
- Department of Microbiology, Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland; (S.S.); (A.L.); (P.D.); (M.P.)
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18
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Advances in RNA-Silencing-Related Resistance against Viruses in Potato. Genes (Basel) 2022; 13:genes13050731. [PMID: 35627117 PMCID: PMC9141481 DOI: 10.3390/genes13050731] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/20/2022] [Accepted: 04/20/2022] [Indexed: 12/16/2022] Open
Abstract
Potato is a major food crop that has the potential to feed the increasing global population. Potato is the fourth most important crop and a staple food for many people worldwide. The traditional breeding of potato poses many challenges because of its autotetraploid nature and its tendency toward inbreeding depression. Moreover, potato crops suffer considerable production losses because of infections caused by plant viruses. In this context, RNA silencing technology has been successfully applied in model and crop species. In this review, we describe the RNA interference (RNAi) mechanisms, including small-interfering RNA, microRNA, and artificial microRNA, which may be used to engineer resistance against potato viruses. We also explore the latest advances in the development of antiviral strategies to enhance resistance against potato virus X, potato virus Y, potato virus A, potato leafroll virus, and potato spindle tuber viroid. Furthermore, the challenges in RNAi that need to be overcome are described in this review. Altogether, this report would be insightful for the researchers attempting to understand the RNAi-mediated resistance against viruses in potato.
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19
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González-Catrilelbún S, Cartagena J, Vargas D, Breguel-Serrano P, Sandino AM, Rivas-Aravena A. The RNA-dependent RNA polymerase of the infectious pancreatic necrosis virus is linked to viral mRNA acting as a cap substitute. J Gen Virol 2022; 103. [DOI: 10.1099/jgv.0.001729] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The infectious pancreatic necrosis virus (IPNV) is responsible for significant economic losses in the aquaculture industry. It is an unenveloped virus with an icosahedral capsid. Its viral genome comprises two dsRNA segments, A and B. Segment A contains a small ORF, which encodes VP5, and a large ORF, which encodes a polyprotein that generates the structural proteins and the viral protease. Segment B encodes the RNA-dependent RNA polymerase (RdRp), called VP1 in this free form, or Vpg when it covalently attaches to the viral RNA. The viral genome does not have cap or poly(A). Instead, each 5′ end is linked to the Vpg. Recently, we demonstrated that mRNA-A contains an internal ribosome entry site (IRES) to command polyprotein synthesis. However, the presence of Vpg on IPNV mRNAs and its impact on cellular translation has not been investigated. This research demonstrates that IPNV mRNAs are linked to Vpg and that this protein inhibits cap-dependent translation on infected cells. Also, it is demonstrated that Vpg interacts with eIF4E and that rapamycin treatment partially diminishes the viral protein synthesis. In addition, we determined that an IRES does not command translation of IPNV mRNA-B. We show that VPg serves as a cap substitute during the initiation of IPNV translation, contributing to understanding the replicative cycle of Birnaviruses. Our results indicate that the viral protein VP1/Vpg is multifunctional, having a significant role during IPNV RNA synthesis as the RdRp and the primer for IPNV RNA synthesis and translation as the viral protein genome, acting as a cap substitute.
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Affiliation(s)
| | - Julio Cartagena
- Laboratorio de Virología, Centro de Biotecnología Acuícola, Universidad de Santiago de Chile, Santiago, Chile
| | - Deborah Vargas
- Laboratorio de Virología, Centro de Biotecnología Acuícola, Universidad de Santiago de Chile, Santiago, Chile
| | - Pamela Breguel-Serrano
- Laboratorio de Virología, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Ana María Sandino
- Laboratorio de Virología, Centro de Biotecnología Acuícola, Universidad de Santiago de Chile, Santiago, Chile
| | - Andrea Rivas-Aravena
- Laboratorio de Virología, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
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20
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Translation of Plant RNA Viruses. Viruses 2021; 13:v13122499. [PMID: 34960768 PMCID: PMC8708638 DOI: 10.3390/v13122499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 12/01/2021] [Accepted: 12/09/2021] [Indexed: 11/16/2022] Open
Abstract
Plant RNA viruses encode essential viral proteins that depend on the host translation machinery for their expression. However, genomic RNAs of most plant RNA viruses lack the classical characteristics of eukaryotic cellular mRNAs, such as mono-cistron, 5′ cap structure, and 3′ polyadenylation. To adapt and utilize the eukaryotic translation machinery, plant RNA viruses have evolved a variety of translation strategies such as cap-independent translation, translation recoding on initiation and termination sites, and post-translation processes. This review focuses on advances in cap-independent translation and translation recoding in plant viruses.
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21
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Khan MA, Kumar P, Akif M, Miyoshi H. Phosphorylation of eukaryotic initiation factor eIFiso4E enhances the binding rates to VPg of turnip mosaic virus. PLoS One 2021; 16:e0259688. [PMID: 34735537 PMCID: PMC8568277 DOI: 10.1371/journal.pone.0259688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 09/29/2021] [Indexed: 11/28/2022] Open
Abstract
Binding of phosphorylated eIFiso4E with viral genome-linked protein (VPg) of turnip mosaic virus was examined by stopped-flow, fluorescence, circular dichroism (CD) spectroscopy, and molecular docking analysis. Phosphorylation of eIFiso4E increased (4-fold) the binding rates as compared to unphosphorylated eIFiso4E with VPg. Stopped-flow kinetic studies of phosphorylated eIFiso4E with VPg showed a concentration-independent conformational change. The dissociation rate was about 3-fold slower for eIFiso4E∙VPg complex upon phosphorylation. Phosphorylation enhanced the association rates and lowered the dissociation rates for the eIFiso4E∙VPg binding, with having higher preferential binding to eIFiso4Ep. Binding rates for the interaction of eIFiso4Ep with VPg increased (6-fold) with an increase in temperature, 278 K to 298 K. The activation energies for binding of eIFiso4Ep and eIFiso4E with VPg were 37.2 ± 2.8 and 52.6 ± 3.6 kJ/mol, respectively. Phosphorylation decreased the activation energy for the binding of eIFiso4E to VPg. The reduced energy barrier suggests more stable platform for eIFiso4Ep∙VPg initiation complex formation, which was further supported by molecular docking analysis. Moreover, far-UV CD studies revealed that VPg formed complex with eIFiso4Ep with substantial change in the secondary structure. These results suggested that phosphorylation, not only reduced the energy barrier and dissociation rate but also enhanced binding rate, and an overall conformational change, which provides a more stable platform for efficient viral translation.
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Affiliation(s)
- Mateen A. Khan
- Department of Life Science, College of Science and General Studies, Alfaisal University, Riyadh, Saudi Arabia
- * E-mail:
| | - Pankaj Kumar
- Department of Biochemistry, School of Life Science, University of Hyderabad, Hyderabad, India
| | - Mohd. Akif
- Department of Biochemistry, School of Life Science, University of Hyderabad, Hyderabad, India
| | - Hiroshi Miyoshi
- Department of Microbiology, St. Marianna University School of Medicine, Kawasaki, Japan
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22
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Pepper Mottle Virus and Its Host Interactions: Current State of Knowledge. Viruses 2021; 13:v13101930. [PMID: 34696360 PMCID: PMC8539092 DOI: 10.3390/v13101930] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/21/2021] [Accepted: 09/22/2021] [Indexed: 01/08/2023] Open
Abstract
Pepper mottle virus (PepMoV) is a destructive pathogen that infects various solanaceous plants, including pepper, bell pepper, potato, and tomato. In this review, we summarize what is known about the molecular characteristics of PepMoV and its interactions with host plants. Comparisons of symptom variations caused by PepMoV isolates in plant hosts indicates a possible relationship between symptom development and genetic variation. Researchers have investigated the PepMoV–plant pathosystem to identify effective and durable genes that confer resistance to the pathogen. As a result, several recessive pvr or dominant Pvr resistance genes that confer resistance to PepMoV in pepper have been characterized. On the other hand, the molecular mechanisms underlying the interaction between these resistance genes and PepMoV-encoded genes remain largely unknown. Our understanding of the molecular interactions between PepMoV and host plants should be increased by reverse genetic approaches and comprehensive transcriptomic analyses of both the virus and the host genes.
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23
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Yang X, Li Y, Wang A. Research Advances in Potyviruses: From the Laboratory Bench to the Field. ANNUAL REVIEW OF PHYTOPATHOLOGY 2021; 59:1-29. [PMID: 33891829 DOI: 10.1146/annurev-phyto-020620-114550] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Potyviruses (viruses in the genus Potyvirus, family Potyviridae) constitute the largest group of known plant-infecting RNA viruses and include many agriculturally important viruses that cause devastating epidemics and significant yield losses in many crops worldwide. Several potyviruses are recognized as the most economically important viral pathogens. Therefore, potyviruses are more studied than other groups of plant viruses. In the past decade, a large amount of knowledge has been generated to better understand potyviruses and their infection process. In this review, we list the top 10 economically important potyviruses and present a brief profile of each. We highlight recent exciting findings on the novel genome expression strategy and the biological functions of potyviral proteins and discuss recent advances in molecular plant-potyvirus interactions, particularly regarding the coevolutionary arms race. Finally, we summarize current disease control strategies, with a focus on biotechnology-based genetic resistance, and point out future research directions.
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Affiliation(s)
- Xiuling Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada;
| | - Yinzi Li
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada;
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada;
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McSweeney AM, Young VL, Ward VK. Norovirus VPg Binds RNA through a Conserved N-Terminal K/R Basic Patch. Viruses 2021; 13:v13071282. [PMID: 34209211 PMCID: PMC8310136 DOI: 10.3390/v13071282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 06/23/2021] [Accepted: 06/26/2021] [Indexed: 11/17/2022] Open
Abstract
The viral protein genome-linked (VPg) of noroviruses is a multi-functional protein that participates in essential roles during the viral replication cycle. Predictive analyses indicate that murine norovirus (MNV) VPg contains a disordered N-terminal region with RNA binding potential. VPg proteins were expressed with an N-terminal spidroin fusion protein in insect cells and the interaction with RNA investigated by electrophoretic mobility shift assays (EMSA) against a series of RNA probes (pentaprobes) representing all possible five nucleotide combinations. MNV VPg and human norovirus (HuNV) VPg proteins were directly bound to RNA in a non-specific manner. To identify amino acids involved in binding to RNA, all basic (K/R) residues in the first 12 amino acids of MNV VPg were mutated to alanine. Removal of the K/R amino acids eliminated RNA binding and is consistent with a K/R basic patch RNA binding motif within the disordered N-terminal region of norovirus VPgs. Finally, we show that mutation of the K/R basic patch required for RNA binding eliminates the ability of MNV VPg to induce a G0/G1 cell cycle arrest.
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Paudel DB, Sanfaçon H. Mapping of sequences in the 5' region and 3' UTR of tomato ringspot virus RNA2 that facilitate cap-independent translation of reporter transcripts in vitro. PLoS One 2021; 16:e0249928. [PMID: 33836032 PMCID: PMC8034749 DOI: 10.1371/journal.pone.0249928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 03/26/2021] [Indexed: 12/18/2022] Open
Abstract
Tomato ringspot virus (ToRSV, genus Nepovirus, family Secoviridae, order Picornavirales) is a bipartite positive-strand RNA virus, with each RNA encoding one large polyprotein. ToRSV RNAs are linked to a 5'-viral genome-linked protein (VPg) and have a 3' polyA tail, suggesting a non-canonical cap-independent translation initiation mechanism. The 3' untranslated regions (UTRs) of RNA1 and RNA2 are unusually long (~1.5 kb) and share several large stretches of sequence identities. Several putative in-frame start codons are present in the 5' regions of the viral RNAs, which are also highly conserved between the two RNAs. Using reporter transcripts containing the 5' region and 3' UTR of the RNA2 of ToRSV Rasp1 isolate (ToRSV-Rasp1) and in vitro wheat germ extract translation assays, we provide evidence that translation initiates exclusively at the first AUG, in spite of a poor codon context. We also show that both the 5' region and 3' UTR of RNA2 are required for efficient cap-independent translation of these transcripts. We identify translation-enhancing elements in the 5' proximal coding region of the RNA2 polyprotein and in the RNA2 3' UTR. Cap-dependent translation of control reporter transcripts was inhibited when RNAs consisting of the RNA2 3' UTR were supplied in trans. Taken together, our results suggest the presence of a CITE in the ToRSV-Rasp1 RNA2 3' UTR that recruits one or several translation factors and facilitates efficient cap-independent translation together with the 5' region of the RNA. Non-overlapping deletion mutagenesis delineated the putative CITE to a 200 nts segment (nts 773-972) of the 1547 nt long 3' UTR. We conclude that the general mechanism of ToRSV RNA2 translation initiation is similar to that previously reported for the RNAs of blackcurrant reversion virus, another nepovirus. However, the position, sequence and predicted structures of the translation-enhancing elements differed between the two viruses.
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Affiliation(s)
- Dinesh Babu Paudel
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - Hélène Sanfaçon
- Summerland Research and Development Centre, Agriculture and Agri-Food Canada, Summerland, BC, Canada
- * E-mail:
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Li Q, Liu N, Liu Q, Zheng X, Lu L, Gao W, Liu Y, Liu Y, Zhang S, Wang Q, Pan J, Chen C, Mi Y, Yang M, Cheng X, Ren G, Yuan YW, Zhang X. DEAD-box helicases modulate dicing body formation in Arabidopsis. SCIENCE ADVANCES 2021; 7:7/18/eabc6266. [PMID: 33910901 PMCID: PMC8081359 DOI: 10.1126/sciadv.abc6266] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 03/10/2021] [Indexed: 05/02/2023]
Abstract
Eukaryotic cells contain numerous membraneless organelles that are made from liquid droplets of proteins and nucleic acids and that provide spatiotemporal control of various cellular processes. However, the molecular mechanisms underlying the formation and rapid stress-induced alterations of these organelles are relatively uncharacterized. Here, we investigated the roles of DEAD-box helicases in the formation and alteration of membraneless nuclear dicing bodies (D-bodies) in Arabidopsis thaliana We uncovered that RNA helicase 6 (RH6), RH8, and RH12 are previously unidentified D-body components. These helicases interact with and promote the phase separation of SERRATE, a key component of D-bodies, and drive the formation of D-bodies through liquid-liquid phase separations (LLPSs). The accumulation of these helicases in the nuclei decreases upon Turnip mosaic virus infections, which couples with the decrease of D-bodies. Our results thus reveal the key roles of RH6, RH8, and RH12 in modulating D-body formation via LLPSs.
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Affiliation(s)
- Qi Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ningkun Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qing Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xingguo Zheng
- Donald Danforth Plant Science Center, St. Louis, MO 63132, USA
| | - Lu Lu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wenrui Gao
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yang Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shicheng Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Qian Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Pan
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Chen Chen
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yingjie Mi
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- Department of Life Sciences, Henan Normal University, Xinxiang, Henan 453007, China
| | - Meiling Yang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaofei Cheng
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin 150030, China
| | - Guodong Ren
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Yao-Wu Yuan
- Department of Ecology and Evolutionary Biology, University of Connecticut, 75 North Eagleville Road, Unit 3043, Storrs, CT 06269, USA
| | - Xiaoming Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
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De S, Pollari M, Varjosalo M, Mäkinen K. Association of host protein VARICOSE with HCPro within a multiprotein complex is crucial for RNA silencing suppression, translation, encapsidation and systemic spread of potato virus A infection. PLoS Pathog 2020; 16:e1008956. [PMID: 33045020 PMCID: PMC7581364 DOI: 10.1371/journal.ppat.1008956] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 10/22/2020] [Accepted: 09/02/2020] [Indexed: 12/17/2022] Open
Abstract
In this study, we investigated the significance of a conserved five-amino acid motif 'AELPR' in the C-terminal region of helper component-proteinase (HCPro) for potato virus A (PVA; genus Potyvirus) infection. This motif is a putative interaction site for WD40 domain-containing proteins, including VARICOSE (VCS). We abolished the interaction site in HCPro by replacing glutamic acid (E) and arginine (R) with alanines (A) to generate HCProWD. These mutations partially eliminated HCPro-VCS co-localization in cells. We have earlier described potyvirus-induced RNA granules (PGs) in which HCPro and VCS co-localize and proposed that they have a role in RNA silencing suppression. We now demonstrate that the ability of HCProWD to induce PGs, introduce VCS into PGs, and suppress RNA silencing was impaired. Accordingly, PVA carrying HCProWD (PVAWD) infected Nicotiana benthamiana less efficiently than wild-type PVA (PVAWT) and HCProWD complemented the lack of HCPro in PVA gene expression only partially. HCPro was purified from PVA-infected leaves as part of high molecular weight (HMW) ribonucleoprotein (RNP) complexes. These complexes were more stable when associated with wild-type HCPro than with HCProWD. Moreover, VCS and two viral components of the HMW-complexes, viral protein genome-linked and cylindrical inclusion protein were specifically decreased in HCProWD-containing HMW-complexes. A VPg-mediated boost in translation of replication-deficient PVA (PVAΔGDD) was observed only if viral RNA expressed wild-type HCPro. The role of VCS-VPg-HCPro coordination in PVA translation was further supported by results from VCS silencing and overexpression experiments and by significantly elevated PVA-derived Renilla luciferase vs PVA RNA ratio upon VPg-VCS co-expression. Finally, we found that PVAWD was unable to form virus particles or to spread systemically in the infected plant. We highlight the role of HCPro-VCS containing multiprotein assemblies associated with PVA RNA in protecting it from degradation, ensuring efficient translation, formation of stable virions and establishment of systemic infection.
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Affiliation(s)
- Swarnalok De
- University of Helsinki, Department of Microbiology and Viikki Plant Science Centre, Finland
| | - Maija Pollari
- University of Helsinki, Department of Microbiology and Viikki Plant Science Centre, Finland
| | | | - Kristiina Mäkinen
- University of Helsinki, Department of Microbiology and Viikki Plant Science Centre, Finland
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Sabharwal P, Savithri HS. Functional Characterization of Pepper Vein Banding Virus-Encoded Proteins and Their Interactions: Implications in Potyvirus Infection. Viruses 2020; 12:v12091037. [PMID: 32957699 PMCID: PMC7551749 DOI: 10.3390/v12091037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 11/16/2022] Open
Abstract
Pepper vein banding virus (PVBV) is a distinct species in the Potyvirus genus which infects economically important plants in several parts of India. Like other potyviruses, PVBV encodes multifunctional proteins, with several interaction partners, having implications at different stages of the potyviral infection. In this review, we summarize the functional characterization of different PVBV-encoded proteins with an emphasis on their interaction partners governing the multifunctionality of potyviral proteins. Intrinsically disordered domains/regions of these proteins play an important role in their interactions with other proteins. Deciphering the function of PVBV-encoded proteins and their interactions with cognitive partners will help in understanding the putative mechanisms by which the potyviral proteins are regulated at different stages of the viral life-cycle. This review also discusses PVBV virus-like particles (VLPs) and their potential applications in nanotechnology. Further, virus-like nanoparticle-cell interactions and intracellular fate of PVBV VLPs are also discussed.
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Walter J, Barra A, Charon J, Tavert-Roudet G, Michon T. Spectroscopic Investigation of the Kinetic Mechanism Involved in the Association of Potyviral VPg with the Host Plant Translation Initiation Factor eIF4E. Int J Mol Sci 2020; 21:ijms21165618. [PMID: 32764527 PMCID: PMC7460627 DOI: 10.3390/ijms21165618] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/30/2020] [Accepted: 07/31/2020] [Indexed: 12/15/2022] Open
Abstract
The infectious cycle of potyviruses requires the formation of a complex between the viral genome-linked protein VPg and the host eukaryotic translation initiation factor 4E, eIF4E. Mutations associated with plant resistance to potyviruses were previously mapped at the eIF4E surface, while on the virus side, mutations leading to plant resistance breaking were identified within the VPg. In the present study, fluorescence spectroscopy was used to probe the contribution of the VPg intrinsically disordered region bearing amino acids determinant of the resistance breaking, to the VPg–eIF4E binding mechanism. Synthetic peptides encompassing the VPg88–120 central region were found to tightly bind to eIF4E. Fluorescence energy transfer experiments show that, upon binding to eIF4E, the N and C termini of the VPg88–111 fragment move closer to one another, at a distance compatible with a α-helix folding. When the VPg112–120 region, which contains amino acids associated with resistance breakdown, is appended to VPg88–111, the complex formation with eIF4E switches from a single-step to a two-step kinetic model. This study revisits a recent investigation of the VPg–eIF4E complex by specifying the contribution of the VPg central helix and its appended disordered region to VPg association with eIF4E.
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Affiliation(s)
- Jocelyne Walter
- INRAE, Biologie du Fruit et Pathologie, University of Bordeaux, UMR 1332, F-33140 Villenave d’Ornon, France; (J.W.); (A.B.); (G.T.-R.)
| | - Amandine Barra
- INRAE, Biologie du Fruit et Pathologie, University of Bordeaux, UMR 1332, F-33140 Villenave d’Ornon, France; (J.W.); (A.B.); (G.T.-R.)
| | - Justine Charon
- Faculty of Sciences, University of Sydney, Charles Perkins Center D17, Camperdown Campus, Sydney, NSW 2006, Australia;
| | - Geneviève Tavert-Roudet
- INRAE, Biologie du Fruit et Pathologie, University of Bordeaux, UMR 1332, F-33140 Villenave d’Ornon, France; (J.W.); (A.B.); (G.T.-R.)
| | - Thierry Michon
- INRAE, Biologie du Fruit et Pathologie, University of Bordeaux, UMR 1332, F-33140 Villenave d’Ornon, France; (J.W.); (A.B.); (G.T.-R.)
- Correspondence: ; Tel.: +33-(0)-557-12-23-91
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Abstract
The stage at which ribosomes are recruited to messenger RNAs (mRNAs) is an elaborate and highly regulated phase of protein synthesis. Upon completion of this step, a ribosome is positioned at an appropriate initiation codon and primed to synthesize the encoded polypeptide product. In most circumstances, this step commits the ribosome to translate the mRNA. We summarize the knowledge regarding the initiation factors implicated in this activity as well as review different mechanisms by which this process is conducted.
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Affiliation(s)
- Jerry Pelletier
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada; , .,Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada.,Department of Oncology, McGill University, Montreal, Quebec H4A 3T2, Canada
| | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada; , .,Rosalind and Morris Goodman Cancer Research Center, McGill University, Montreal, Quebec H3A 1A3, Canada
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31
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Geng G, Yu C, Li X, Yuan X. A unique internal ribosome entry site representing a dynamic equilibrium state of RNA tertiary structure in the 5'-UTR of Wheat yellow mosaic virus RNA1. Nucleic Acids Res 2020; 48:390-404. [PMID: 31713626 PMCID: PMC7145537 DOI: 10.1093/nar/gkz1073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 10/23/2019] [Accepted: 10/31/2019] [Indexed: 02/02/2023] Open
Abstract
Internal ribosome entry sites (IRESes) were first reported in RNA viruses and subsequently identified in cellular mRNAs. In this study, IRES activity of the 5'-UTR in Wheat yellow mosaic virus (WYMV) RNA1 was identified, and the 3'-UTR synergistically enhanced this IRES activity via long-distance RNA-RNA interaction between C80U81and A7574G7575. Within the 5'-UTR, the hairpin 1(H1), flexible hairpin 2 (H2) and linker region (LR1) between H1 and H2 played an essential role in cap-independent translation, which is associated with the structural stability of H1, length of discontinuous stems and nucleotide specificity of the H2 upper loop and the long-distance RNA-RNA interaction sites in LR1. The H2 upper loop is a target region of the eIF4E. Cytosines (C55, C66, C105 and C108) in H1 and H2 and guanines (G73, G79 and G85) in LR1 form discontinuous and alternative base pairing to maintain the dynamic equilibrium state, which is used to elaborately regulate translation at a suitable level. The WYMV RNA1 5'-UTR contains a novel IRES, which is different from reported IRESes because of the dynamic equilibrium state. It is also suggested that robustness not at the maximum level of translation is the selection target during evolution of WYMV RNA1.
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Affiliation(s)
- Guowei Geng
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
| | - Chengming Yu
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
| | - Xiangdong Li
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
| | - Xuefeng Yuan
- Department of Plant Pathology, College of Plant Protection, Shandong Agricultural University, Shandong Province Key Laboratory of Agricultural Microbiology, Tai'an 271018, P.R. China
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Saha S, Mäkinen K. Insights into the Functions of eIF4E-Biding Motif of VPg in Potato Virus A Infection. Viruses 2020; 12:E197. [PMID: 32053987 PMCID: PMC7077193 DOI: 10.3390/v12020197] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 02/05/2020] [Accepted: 02/07/2020] [Indexed: 12/14/2022] Open
Abstract
The interaction between the viral protein genome-linked (VPg) and eukaryotic initiation factor 4E (eIF4E) or eIF(iso)4E of the host plays a crucial role in potyvirus infection. The VPg of potato virus A (PVA) contains the Tyr-X-X-X-X-Leu-phi (YXXXLΦ) binding motif for eIF(iso)4E. In order to investigate its role in PVA infection, we substituted the conserved tyrosine and leucine residues of the motif with alanine residues in the infectious cDNA of PVA (PVAVPgmut). PVAVPgmut RNA replicated in infiltrated leaves, but RNA accumulation remained low. Systemic infection occurred only if a reversion to wild type PVA occurred. VPg was able to stabilize PVA RNA and enhance the expression of Renilla luciferase (3'RLUC) from the 3' end of the PVA genome. VPgmut could not support either PVA RNA stabilization or enhanced 3'RLUC expression. The RNA silencing suppressor helper-component proteinase (HCPro) is responsible for the formation of PVA-induced RNA granules (PGs) during infection. While VPgmut increased the number of PG-like foci, the percentage of PVA RNA co-localization with PGs was reduced from 86% to 20%. A testable hypothesis for future studies based on these results is that the binding of eIF(iso)4E to PVA VPg via the YXXXLΦ motif is required for PVA RNA stabilization, as well as the transfer to the RNA silencing suppression pathway and, further, to polysomes for viral protein synthesis.
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Affiliation(s)
| | - Kristiina Mäkinen
- Department of Microbiology and Viikki Plant Science Centre, University of Helsinki, 00014 Helsinki, Finland;
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33
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[Recessive resistance to plant viruses by the deficiency of eukaryotic translation initiation factor genes.]. Uirusu 2020; 70:61-68. [PMID: 33967115 DOI: 10.2222/jsv.70.61] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Plant viruses, obligate parasitic pathogens, utilize a variety of host plant factors in the process of their infection due to the limited number of genes encoded in their own genomes. The genes encoding these host factors are called susceptibility genes because they are responsible for the susceptibility of plants to viruses. Plants lacking or having mutations in a susceptibility gene essential for the infection of a virus acquire resistance to the virus. Such resistance trait is called recessive resistance because of the recessive inherited characteristics. Recessive resistance is reported to account for about half of the plant viral resistance loci mapped in known cultivated crops. Eukaryotic translation initiation factor (eIF) 4E family genes are well-known susceptibility genes. Although there are many reports about eIF4E-mediated recessive resistance to plant viruses, the mechanistic insight of the resistance is still limited. Here we review focusing on studies that have elucidated the mechanism of eIF4E-mediated recessive resistance.
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Ala-Poikela M, Rajamäki ML, Valkonen JP. A Novel Interaction Network Used by Potyviruses in Virus-Host Interactions at the Protein Level. Viruses 2019; 11:E1158. [PMID: 31847316 PMCID: PMC6950583 DOI: 10.3390/v11121158] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 12/30/2022] Open
Abstract
Host proteins that are central to infection of potyviruses (genus Potyvirus; family Potyviridae) include the eukaryotic translation initiation factors eIF4E and eIF(iso)4E. The potyviral genome-linked protein (VPg) and the helper component proteinase (HCpro) interact with each other and with eIF4E and eIF(iso)4E and proteins are involved in the same functions during viral infection. VPg interacts with eIF4E/eIF(iso)4E via the 7-methylguanosine cap-binding region, whereas HCpro interacts with eIF4E/eIF(iso)4E via the 4E-binding motif YXXXXLΦ, similar to the motif in eIF4G. In this study, HCpro and VPg were found to interact in the nucleus, nucleolus, and cytoplasm in cells infected with the potyvirus potato virus A (PVA). In the cytoplasm, interactions between HCpro and VPg occurred in punctate bodies not associated with viral replication vesicles. In addition to HCpro, the 4E-binding motif was recognized in VPg of PVA. Mutations in the 4E-binding motif of VPg from PVA weakened interactions with eIF4E and heavily reduced PVA virulence. Furthermore, mutations in the 4G-binding domain of eIF4E reduced interactions with VPg and abolished interactions with HCpro. Thus, HCpro and VPg can both interact with eIF4E using the 4E-binding motif. Our results suggest a novel interaction network used by potyviruses to interact with host plants via translation initiation factors.
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Affiliation(s)
| | - Minna-Liisa Rajamäki
- Department of Agricultural Sciences, University of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland;
| | - Jari P.T. Valkonen
- Department of Agricultural Sciences, University of Helsinki, P.O. Box 27, FI-00014 Helsinki, Finland;
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35
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Dauphinee AN, Cardoso C, Dalman K, Ohlsson JA, Fick SB, Robert S, Hicks GR, Bozhkov PV, Minina EA. Chemical Screening Pipeline for Identification of Specific Plant Autophagy Modulators. PLANT PHYSIOLOGY 2019; 181:855-866. [PMID: 31488572 PMCID: PMC6836817 DOI: 10.1104/pp.19.00647] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 08/14/2019] [Indexed: 05/18/2023]
Abstract
Autophagy is a major catabolic process in eukaryotes with a key role in homeostasis, programmed cell death, and aging. In plants, autophagy is also known to regulate agronomically important traits such as stress resistance, longevity, vegetative biomass, and seed yield. Despite its significance, there is still a shortage of reliable tools modulating plant autophagy. Here, we describe the first robust pipeline for identification of specific plant autophagy-modulating compounds. Our screening protocol comprises four phases: (1) high-throughput screening of chemical compounds in cell cultures of tobacco (Nicotiana tabacum); (2) confirmation of the identified hits in planta using Arabidopsis (Arabidopsis thaliana); (3) further characterization of the effect using conventional molecular biology methods; and (4) verification of chemical specificity on autophagy in planta. The methods detailed here streamline the identification of specific plant autophagy modulators and aid in unraveling the molecular mechanisms of plant autophagy.
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Affiliation(s)
- Adrian N Dauphinee
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
| | - Catarina Cardoso
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
- Plant Genetics, School of Life Science Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Kerstin Dalman
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
| | - Jonas A Ohlsson
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
| | | | - Stéphanie Robert
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, 901 83 Umea, Sweden
| | - Glenn R Hicks
- Center for Plant Cell Biology and Department of Botany and Plant Sciences, University of California, Riverside, California, 92521
| | - Peter V Bozhkov
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
| | - Elena A Minina
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala SE-750 07, Sweden
- Centre for Organismal Studies (COS), Heidelberg University, 69120 Heidelberg, Germany
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36
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Saha S, Hafren A, Mäkinen K. Dynamics of Protein Accumulation from the 3' End of Viral RNA Are Different from Those in the Rest of the Genome in Potato Virus A Infection. J Virol 2019; 93:e00721-19. [PMID: 31341041 PMCID: PMC6744237 DOI: 10.1128/jvi.00721-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/14/2019] [Indexed: 01/18/2023] Open
Abstract
One large open reading frame (ORF) encodes 10 potyviral proteins. We compared the accumulation of cylindrical inclusion (CI) protein from the middle, coat protein (CP) from the 3'end, and Renilla luciferase (RLUC) from two distinct locations in potato virus A (PVA) RNA. 5' RLUC was expressed from an rluc gene inserted between the P1 and helper component proteinase (HCPro) cistrons, and 3' RLUC was expressed from the gene inserted between the RNA polymerase and CP cistrons. Viral protein and RNA accumulation were quantitated (i) when expressed from PVA RNA in the presence of ectopically expressed genome-linked viral protein (VPg) and auxiliary proteins and (ii) at different time points during natural infection. The rate and timing of 3' RLUC and CP accumulation were found to be different from those of 5' RLUC and CI. Ectopic expression of VPg boosted PVA RNA, 3' RLUC, and, together with HCPro, CP accumulation, whereas 5' RLUC and CI accumulation remained unaffected regardless of the increased viral RNA amount. In natural infection, the rate of the noteworthy minute early accumulation of 3' RLUC accelerated toward the end of infection. 5' RLUC accumulation, which was already pronounced at 2 days postinfection, increased moderately and stabilized to a constant level by day 5, whereas PVA RNA and CP levels continued to increase throughout the infection. We propose that these observations connect with the mechanisms by which potyvirus infection limits CP accumulation during early infection and specifically supports its accumulation late in infection, but follow-up studies are required to understand the mechanism of how this occurs.IMPORTANCE The results of this study suggest that the dynamics of potyviral protein accumulation are regulated differentially from the 3' end of viral RNA than from the rest of the genome, the significance of which would be to satisfy the needs of replication early and particle assembly late in infection.
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Affiliation(s)
- Shreya Saha
- Faculty of Agriculture and Forestry, Department of Microbiology, Viikki Plant Sciences Center, University of Helsinki, Helsinki, Finland
| | - Anders Hafren
- Faculty of Agriculture and Forestry, Department of Microbiology, Viikki Plant Sciences Center, University of Helsinki, Helsinki, Finland
| | - Kristiina Mäkinen
- Faculty of Agriculture and Forestry, Department of Microbiology, Viikki Plant Sciences Center, University of Helsinki, Helsinki, Finland
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Abstract
Potyviridae is the largest family of plant-infecting RNA viruses, encompassing over 30% of known plant viruses. The family is closely related to animal picornaviruses such as enteroviruses and belongs to the picorna-like supergroup. Like all other picorna-like viruses, potyvirids employ polyprotein processing as a gene expression strategy and have single-stranded, positive-sense RNA genomes, most of which are monopartite with a long open reading frame. The potyvirid polyproteins are highly conserved in the central and carboxy-terminal regions. In contrast, the N-terminal region is hypervariable and contains position-specific mutations resulting from transcriptional slippage during viral replication, leading to translational frameshift to produce additional viral proteins essential for viral infection. Some potyvirids even lack one of the N-terminal proteins P1 or helper component-protease and have a genus-specific or species-specific protein instead. This review summarizes current knowledge about the conserved and divergent features of potyvirid genomes and biological relevance and discusses future research directions.
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Affiliation(s)
- Hongguang Cui
- College of Plant Protection, Hainan University, Haikou, Hainan 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, Haikou, Hainan 570228, China
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada
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Bastet A, Zafirov D, Giovinazzo N, Guyon‐Debast A, Nogué F, Robaglia C, Gallois J. Mimicking natural polymorphism in eIF4E by CRISPR-Cas9 base editing is associated with resistance to potyviruses. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:1736-1750. [PMID: 30784179 PMCID: PMC6686125 DOI: 10.1111/pbi.13096] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/11/2019] [Accepted: 02/13/2019] [Indexed: 05/08/2023]
Abstract
In many crop species, natural variation in eIF4E proteins confers resistance to potyviruses. Gene editing offers new opportunities to transfer genetic resistance to crops that seem to lack natural eIF4E alleles. However, because eIF4E are physiologically important proteins, any introduced modification for virus resistance must not bring adverse phenotype effects. In this study, we assessed the role of amino acid substitutions encoded by a Pisum sativum eIF4E virus-resistance allele (W69L, T80D S81D, S84A, G114R and N176K) by introducing them independently into the Arabidopsis thaliana eIF4E1 gene, a susceptibility factor to the Clover yellow vein virus (ClYVV). Results show that most mutations were sufficient to prevent ClYVV accumulation in plants without affecting plant growth. In addition, two of these engineered resistance alleles can be combined with a loss-of-function eIFiso4E to expand the resistance spectrum to other potyviruses. Finally, we use CRISPR-nCas9-cytidine deaminase technology to convert the Arabidopsis eIF4E1 susceptibility allele into a resistance allele by introducing the N176K mutation with a single-point mutation through C-to-G base editing to generate resistant plants. This study shows how combining knowledge on pathogen susceptibility factors with precise genome-editing technologies offers a feasible solution for engineering transgene-free genetic resistance in plants, even across species barriers.
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Affiliation(s)
- Anna Bastet
- GAFLINRAMontfavetFrance
- Laboratoire de Génétique et Biophysique des PlantesCEACNRSBIAMAix Marseille UniversityMarseilleFrance
| | - Delyan Zafirov
- GAFLINRAMontfavetFrance
- Laboratoire de Génétique et Biophysique des PlantesCEACNRSBIAMAix Marseille UniversityMarseilleFrance
| | | | - Anouchka Guyon‐Debast
- Institut Jean‐Pierre BourginINRAAgroParisTechCNRSUniversité Paris‐SaclayVersaillesFrance
| | - Fabien Nogué
- Institut Jean‐Pierre BourginINRAAgroParisTechCNRSUniversité Paris‐SaclayVersaillesFrance
| | - Christophe Robaglia
- Laboratoire de Génétique et Biophysique des PlantesCEACNRSBIAMAix Marseille UniversityMarseilleFrance
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Mao Y, Sun X, Shen J, Gao F, Qiu G, Wang T, Nie X, Zhang W, Gao Y, Bai Y. Molecular Evolutionary Analysis of Potato Virus Y Infecting Potato Based on the VPg Gene. Front Microbiol 2019; 10:1708. [PMID: 31402905 PMCID: PMC6676787 DOI: 10.3389/fmicb.2019.01708] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/10/2019] [Indexed: 11/21/2022] Open
Abstract
Potato virus Y (PVY) is an important plant pathogen infecting solanaceous crops, causing significant losses to global potato and tobacco production. Some aspects of the plant pathology and molecular biology of PVY have been studied intensively, but the evolutionary dynamics of this virus are poorly understood. Here, we performed a comprehensive set of rigorous evolutionary analyses using 177 nucleotide sequences of the viral genome linked protein (VPg) gene, which interacts with the plant eukaryotic translation initiation factor 4E (eIF4E). Our Bayesian analysis reveals that the VPg gene of PVY has been evolving at a rate of 5.60 × 10–4 subs/site/year (95% credibility interval 3.35 × 10–4–8.17 × 10–4), which is equivalent to those of other plant-infecting RNA viruses. We identified different evolutionary constraints on the two clades of PVY, clade N and clade O, whose diverge time were estimated at the year 1861 CE (95% credibility interval 1750–1948 CE). We also found that genetic variations were correlated with geographic regions, suggesting that the evolution of this pathogen is strongly affected by geographical associated factors. Taken together, the results of our study have potential implications for the control strategies of PVY.
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Affiliation(s)
- Yanzhi Mao
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Xuhong Sun
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Jianguo Shen
- Inspection and Quarantine Technology Center, Fujian Exit-Entry, Inspection and Quarantine Bureau, Fuzhou, China
| | - Fangluan Gao
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Guangwei Qiu
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Teng Wang
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Xianzhou Nie
- Fredericton Research and Development Centre, Agriculture and Agri-Food Canada, Fredericton, NB, Canada
| | - Wei Zhang
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Yanling Gao
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
| | - Yanju Bai
- Heilongjiang Academy of Agricultural Sciences, Harbin, China
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40
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Figueira ADR, Geraldino-Duarte PS, Pinzón Nuñez AM, Lent JV, Galvino-Costa SBF, Farman M, Goodin MM. Characterization of Soybean yellow shoot virus, a New Member of the Family Potyviridae Infecting Soybean Plants in Brazil. PLANT DISEASE 2019; 103:1172-1180. [PMID: 30907693 DOI: 10.1094/pdis-06-18-1067-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A new virus species, belonging to the family Potyviridae and capable of infecting most of the soybean cultivars grown in Brazil, was collected in Lavras, Minas Gerais, Brazil, and named Soybean yellow shoot virus (SoyYSV). In this study, the complete 9,052-nucleotide genome of SoyYSV was determined and the structural, biological, and molecular properties of the virus were investigated. The SoyYSV genome encoded a single polyprotein that could be subsequently cleaved, generating 11 proteins. The SoyYSV genome shared 49% nucleotide and 36% amino acid sequence identity with Blackberry virus Y. However, the P1 protein of SoyYSV was much smaller and lacked the ALK1 domain characteristic of the genus Brambyvirus. Electron microscopy revealed flexuous filamentous virus particles, 760 to 780 nm in length, and cytoplasmic inclusions typical of those found in plant cells infected with Potyviridae species. In addition to soybean, SoyYSV infected species in the Amaranthaceae, Caricaceae, Fabaceae, and Solanaceae families. Among the most common potyviruses present in Brazil, only SoyYSV induced local necrotic lesions in Carica papaya L. SoyYSV was transmissible by Myzus persicae and Aphis gossypii but lacked the HC-Pro domain required for aphid transmission in other potyviruses. No seed transmission in soybean was observed.
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Affiliation(s)
- Antonia Dos Reis Figueira
- 1 Department of Fitopatologia, Universidade Federal de Lavras, Lavras, Minas Gerais 37200-000, Brazil
| | | | | | - Jan van Lent
- 2 Department of Plant Science, Wageningen University and Research, 6708 PB Wageningen, The Netherlands; and
| | - Suellen B F Galvino-Costa
- 1 Department of Fitopatologia, Universidade Federal de Lavras, Lavras, Minas Gerais 37200-000, Brazil
| | - M Farman
- 3 Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, U.S.A
| | - Michael M Goodin
- 3 Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, U.S.A
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41
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Eskelin K, Varjosalo M, Ravantti J, Mäkinen K. Ribosome profiles and riboproteomes of healthy and Potato virus A- and Agrobacterium-infected Nicotiana benthamiana plants. MOLECULAR PLANT PATHOLOGY 2019; 20:392-409. [PMID: 30375150 PMCID: PMC6637900 DOI: 10.1111/mpp.12764] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Nicotiana benthamiana is an important model plant for plant-microbe interaction studies. Here, we compared ribosome profiles and riboproteomes of healthy and infected N. benthamiana plants. We affinity purified ribosomes from transgenic leaves expressing a FLAG-tagged ribosomal large subunit protein RPL18B of Arabidopsis thaliana. Purifications were prepared from healthy plants and plants that had been infiltrated with Agrobacterium tumefaciens carrying infectious cDNA of Potato virus A (PVA) or firefly luciferase gene, referred to here as PVA- or Agrobacterium-infected plants, respectively. Plants encode a number of paralogous ribosomal proteins (r-proteins). The N. benthamiana riboproteome revealed approximately 6600 r-protein hits representing 424 distinct r-proteins that were members of 71 of the expected 81 r-protein families. Data are available via ProteomeXchange with identifier PXD011602. The data indicated that N. benthamiana ribosomes are heterogeneous in their r-protein composition. In PVA-infected plants, the number of identified r-protein paralogues was lower than in Agrobacterium-infected or healthy plants. A. tumefaciens proteins did not associate with ribosomes, whereas ribosomes from PVA-infected plants co-purified with viral cylindrical inclusion protein and helper component proteinase, reinforcing their possible role in protein synthesis during virus infection. In addition, viral NIa protease-VPg, RNA polymerase NIb and coat protein were occasionally detected. Infection did not affect the proportions of ribosomal subunits or the monosome to polysome ratio, suggesting that no overall alteration in translational activity took place on infection with these pathogens. The riboproteomic data of healthy and pathogen-infected N. benthamiana will be useful for studies on the specific use of r-protein paralogues to control translation in infected plants.
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Affiliation(s)
- Katri Eskelin
- Department of Microbiology, Faculty of Agriculture and ForestryUniversity of HelsinkiPO Box 56FI‐00014Finland
- Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental SciencesUniversity of HelsinkiPO Box 56FI‐00014Finland
| | - Markku Varjosalo
- Institute of BiotechnologyUniversity of HelsinkiPO Box 65FI‐00014Finland
| | - Janne Ravantti
- Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental SciencesUniversity of HelsinkiPO Box 56FI‐00014Finland
| | - Kristiina Mäkinen
- Department of Microbiology, Faculty of Agriculture and ForestryUniversity of HelsinkiPO Box 56FI‐00014Finland
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42
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Gomez MA, Lin ZD, Moll T, Chauhan RD, Hayden L, Renninger K, Beyene G, Taylor NJ, Carrington JC, Staskawicz BJ, Bart RS. Simultaneous CRISPR/Cas9-mediated editing of cassava eIF4E isoforms nCBP-1 and nCBP-2 reduces cassava brown streak disease symptom severity and incidence. PLANT BIOTECHNOLOGY JOURNAL 2019; 17:421-434. [PMID: 30019807 PMCID: PMC6335076 DOI: 10.1111/pbi.12987] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/27/2018] [Indexed: 05/02/2023]
Abstract
Cassava brown streak disease (CBSD) is a major constraint on cassava yields in East and Central Africa and threatens production in West Africa. CBSD is caused by two species of positive-sense RNA viruses belonging to the family Potyviridae, genus Ipomovirus: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Diseases caused by the family Potyviridae require the interaction of viral genome-linked protein (VPg) and host eukaryotic translation initiation factor 4E (eIF4E) isoforms. Cassava encodes five eIF4E proteins: eIF4E, eIF(iso)4E-1, eIF(iso)4E-2, novel cap-binding protein-1 (nCBP-1), and nCBP-2. Protein-protein interaction experiments consistently found that VPg proteins associate with cassava nCBPs. CRISPR/Cas9-mediated genome editing was employed to generate ncbp-1, ncbp-2, and ncbp-1/ncbp-2 mutants in cassava cultivar 60444. Challenge with CBSV showed that ncbp-1/ncbp-2 mutants displayed delayed and attenuated CBSD aerial symptoms, as well as reduced severity and incidence of storage root necrosis. Suppressed disease symptoms were correlated with reduced virus titre in storage roots relative to wild-type controls. Our results demonstrate the ability to modify multiple genes simultaneously in cassava to achieve tolerance to CBSD. Future studies will investigate the contribution of remaining eIF4E isoforms on CBSD and translate this knowledge into an optimized strategy for protecting cassava from disease.
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Affiliation(s)
- Michael A. Gomez
- Department of Plant and Microbial Biology and Innovative Genomics InstituteUniversity of CaliforniaBerkeleyCAUSA
| | | | | | | | - Luke Hayden
- Donald Danforth Plant Science CenterSt. LouisMOUSA
| | | | - Getu Beyene
- Donald Danforth Plant Science CenterSt. LouisMOUSA
| | | | | | - Brian J. Staskawicz
- Department of Plant and Microbial Biology and Innovative Genomics InstituteUniversity of CaliforniaBerkeleyCAUSA
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Üstün S, Hafrén A, Liu Q, Marshall RS, Minina EA, Bozhkov PV, Vierstra RD, Hofius D. Bacteria Exploit Autophagy for Proteasome Degradation and Enhanced Virulence in Plants. THE PLANT CELL 2018; 30:668-685. [PMID: 29500318 PMCID: PMC5894834 DOI: 10.1105/tpc.17.00815] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 02/09/2018] [Accepted: 03/01/2018] [Indexed: 05/21/2023]
Abstract
Autophagy and the ubiquitin-proteasome system (UPS) are two major protein degradation pathways implicated in the response to microbial infections in eukaryotes. In animals, the contribution of autophagy and the UPS to antibacterial immunity is well documented and several bacteria have evolved measures to target and exploit these systems to the benefit of infection. In plants, the UPS has been established as a hub for immune responses and is targeted by bacteria to enhance virulence. However, the role of autophagy during plant-bacterial interactions is less understood. Here, we have identified both pro- and antibacterial functions of autophagy mechanisms upon infection of Arabidopsis thaliana with virulent Pseudomonas syringae pv tomato DC3000 (Pst). We show that Pst activates autophagy in a type III effector (T3E)-dependent manner and stimulates the autophagic removal of proteasomes (proteaphagy) to support bacterial proliferation. We further identify the T3E Hrp outer protein M1 (HopM1) as a principle mediator of autophagy-inducing activities during infection. In contrast to the probacterial effects of Pst-induced proteaphagy, NEIGHBOR OF BRCA1-dependent selective autophagy counteracts disease progression and limits the formation of HopM1-mediated water-soaked lesions. Together, we demonstrate that distinct autophagy pathways contribute to host immunity and bacterial pathogenesis during Pst infection and provide evidence for an intimate crosstalk between proteasome and autophagy in plant-bacterial interactions.
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Affiliation(s)
- Suayib Üstün
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Anders Hafrén
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Qinsong Liu
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Richard S Marshall
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri 63130
| | - Elena A Minina
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Peter V Bozhkov
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Richard D Vierstra
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri 63130
| | - Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
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44
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De S, Chavez‐Calvillo G, Wahlsten M, Mäkinen K. Disruption of the methionine cycle and reduced cellular gluthathione levels underlie potex-potyvirus synergism in Nicotiana benthamiana. MOLECULAR PLANT PATHOLOGY 2018; 19:1820-1835. [PMID: 29363853 PMCID: PMC6638099 DOI: 10.1111/mpp.12661] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 01/15/2018] [Accepted: 01/22/2018] [Indexed: 05/21/2023]
Abstract
Infection caused by the synergistic interaction of two plant viruses is typically manifested by severe symptoms and increased accumulation of either virus. In potex-potyviral synergism, the potyviral RNA silencing suppressor helper component proteinase (HCPro) is known to enhance the pathogenicity of the potexvirus counterpart. In line with this, Potato virus X (PVX; genus Potexvirus) genomic RNA (gRNA) accumulation and gene expression from subgenomic RNA (sgRNA) are increased in Nicotiana benthamiana by Potato virus A (PVA; genus Potyvirus) HCPro expression. Recently, we have demonstrated that PVA HCPro interferes with the host cell methionine cycle by interacting with its key enzymes S-adenosyl-l-methionine synthetase (SAMS) and S-adenosyl-l-homocysteine hydrolase (SAHH). To study the involvement of methionine cycle enzymes in PVX infection, we knocked down SAMS and SAHH. Increased PVX sgRNA expression between 3 and 9 days post-infiltration (dpi) and upregulation of (-)-strand gRNA accumulation at 9 dpi were observed in the SAHH-silenced background. We found that SAMS and SAHH silencing also caused a significant reduction in glutathione (GSH) concentration, specifically in PVX-infected plants between 2 and 9 dpi. Interestingly, HCPro expression in PVX-infected plants caused an even stronger reduction in GSH levels than did SAMS + SAHH silencing and a similar level of reduction was also achieved by knocking down GSH synthetase. PVX sgRNA expression was increased in the GSH synthetase-silenced background. GSH is a major antioxidant of plant cells and therefore GSH shortage may explain the strong oxidative stress and severe symptoms observed during potex-potyvirus mixed infection.
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Affiliation(s)
- Swarnalok De
- Department of Food and Environmental Sciences, Viikki Plant Sciences CentreUniversity of HelsinkiHelsinki 00014Finland
| | - Gabriela Chavez‐Calvillo
- Department of Food and Environmental Sciences, Viikki Plant Sciences CentreUniversity of HelsinkiHelsinki 00014Finland
- Present address:
Department of Entomology and Plant PathologyAuburn UniversityAuburn36849, ALUSA
| | - Matti Wahlsten
- Department of Food and Environmental Sciences, Viikki Plant Sciences CentreUniversity of HelsinkiHelsinki 00014Finland
| | - Kristiina Mäkinen
- Department of Food and Environmental Sciences, Viikki Plant Sciences CentreUniversity of HelsinkiHelsinki 00014Finland
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45
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Hafrén A, Üstün S, Hochmuth A, Svenning S, Johansen T, Hofius D. Turnip Mosaic Virus Counteracts Selective Autophagy of the Viral Silencing Suppressor HCpro. PLANT PHYSIOLOGY 2018; 176:649-662. [PMID: 29133371 PMCID: PMC5761789 DOI: 10.1104/pp.17.01198] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/10/2017] [Indexed: 05/19/2023]
Abstract
Autophagy is a conserved intracellular degradation pathway and has emerged as a key mechanism of antiviral immunity in metazoans, including the selective elimination of viral components. In turn, some animal viruses are able to escape and modulate autophagy for enhanced pathogenicity. Whether host autophagic responses and viral countermeasures play similar roles in plant-virus interactions is not well understood. Here, we have identified selective autophagy as antiviral pathway during plant infection with turnip mosaic virus (TuMV), a positive-stranded RNA potyvirus. We show that the autophagy cargo receptor NBR1 suppresses viral accumulation by targeting the viral RNA silencing suppressor helper-component proteinase (HCpro), presumably in association with virus-induced RNA granules. Intriguingly, TuMV seems to antagonize NBR1-dependent autophagy during infection by the activity of distinct viral proteins, thereby limiting its antiviral capacity. We also found that NBR1-independent bulk autophagy prevents premature plant death, thus extending the lifespan of virus reservoirs and particle production. Together, our study highlights a conserved role of selective autophagy in antiviral immunity and suggests the evolvement of viral protein functions to inhibit autophagy processes, despite a potential trade-off in host survival.
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Affiliation(s)
- Anders Hafrén
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Suayib Üstün
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Anton Hochmuth
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Steingrim Svenning
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsø - The Arctic University of Norway, 9037 Tromsø, Norway
| | - Terje Johansen
- Molecular Cancer Research Group, Institute of Medical Biology, University of Tromsø - The Arctic University of Norway, 9037 Tromsø, Norway
| | - Daniel Hofius
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences (SLU) and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
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46
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Tavert-Roudet G, Anne A, Barra A, Chovin A, Demaille C, Michon T. The Potyvirus Particle Recruits the Plant Translation Initiation Factor eIF4E by Means of the VPg covalently Linked to the Viral RNA. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2017; 30:754-762. [PMID: 28609214 DOI: 10.1094/mpmi-04-17-0091-r] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The viral protein genome-linked (VPg) of potyviruses is a protein covalently linked to the 5' end of viral RNA. It interacts with eIF4E, a component of the cellular translation initiation complex. It has been suggested that the 5' RNA-linked VPg could mimic the cellular mRNA cap, promoting synthesis of viral proteins. Here, we report evidence for recruitment of the plant eIF4E by Lettuce mosaic virus (LMV, potyvirus) particles via the 5' RNA-linked VPg. Analysis of the viral population was performed by enzyme-linked immunosorbent assay-based tests, either with crude extracts of LMV-infected tissues or purified viral particles. In both cases, LMV-VPg and LMV-eIF4E subpopulations could be detected. After reaching a maximum within the first 2 weeks postinoculation, these populations decreased and very few labeled particles were found later than 3 weeks postinoculation. The central domain of VPg (CD-VPg) was found to be exposed at the surface of the particles. Using a purified recombinant lettuce eIF4E and CD-VPg-specific antibodies, we demonstrate that the plant factor binds to the VPg via its central domain. Moreover, the plant eIF4E factor could be imaged at one end of the particles purified from LMV plant extracts, by immunoredox atomic force microscopy coupled to scanning electrochemical microscopy. We discuss the biological significance of these results.
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Affiliation(s)
| | - Agnès Anne
- 2 Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Amandine Barra
- 1 UMR 1332 BFP, INRA, Université Bordeaux, 33883 Villenave d'Ornon, France; and
| | - Arnaud Chovin
- 2 Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Christophe Demaille
- 2 Laboratoire d'Electrochimie Moléculaire, UMR 7591 CNRS, Université Paris Diderot, Sorbonne Paris Cité, 15 rue Jean-Antoine de Baïf, F-75205 Paris Cedex 13, France
| | - Thierry Michon
- 1 UMR 1332 BFP, INRA, Université Bordeaux, 33883 Villenave d'Ornon, France; and
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47
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Miras M, Truniger V, Silva C, Verdaguer N, Aranda MA, Querol-Audí J. Structure of eIF4E in Complex with an eIF4G Peptide Supports a Universal Bipartite Binding Mode for Protein Translation. PLANT PHYSIOLOGY 2017; 174:1476-1491. [PMID: 28522457 PMCID: PMC5490897 DOI: 10.1104/pp.17.00193] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 05/15/2017] [Indexed: 05/20/2023]
Abstract
The association-dissociation of the cap-binding protein eukaryotic translation initiation factor 4E (eIF4E) with eIF4G is a key control step in eukaryotic translation. The paradigm on the eIF4E-eIF4G interaction states that eIF4G binds to the dorsal surface of eIF4E through a single canonical alpha-helical motif, while metazoan eIF4E-binding proteins (m4E-BPs) advantageously compete against eIF4G via bimodal interactions involving this canonical motif and a second noncanonical motif of the eIF4E surface. Metazoan eIF4Gs share this extended binding interface with m4E-BPs, with significant implications on the understanding of translation regulation and the design of therapeutic molecules. Here we show the high-resolution structure of melon (Cucumis melo) eIF4E in complex with a melon eIF4G peptide and propose the first eIF4E-eIF4G structural model for plants. Our structural data together with functional analyses demonstrate that plant eIF4G binds to eIF4E through both the canonical and noncanonical motifs, similarly to metazoan eIF4E-eIF4G complexes. As in the case of metazoan eIF4E-eIF4G, this may have very important practical implications, as plant eIF4E-eIF4G is also involved in a significant number of plant diseases. In light of our results, a universal eukaryotic bipartite mode of binding to eIF4E is proposed.
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Affiliation(s)
- Manuel Miras
- Centro de Edafología y Biología Aplicada del Segura (CEBAS), Consejo Superior de Investigaciones Científicas (CSIC), 30100 Espinardo, Murcia, Spain
| | - Verónica Truniger
- Centro de Edafología y Biología Aplicada del Segura (CEBAS), Consejo Superior de Investigaciones Científicas (CSIC), 30100 Espinardo, Murcia, Spain
| | - Cristina Silva
- Institut de Biologia Molecular de Barcelona/CSIC, Parc Científic de Barcelona, 08028 Barcelona, Spain
| | - Núria Verdaguer
- Institut de Biologia Molecular de Barcelona/CSIC, Parc Científic de Barcelona, 08028 Barcelona, Spain
| | - Miguel A Aranda
- Centro de Edafología y Biología Aplicada del Segura (CEBAS), Consejo Superior de Investigaciones Científicas (CSIC), 30100 Espinardo, Murcia, Spain
| | - Jordi Querol-Audí
- Institut de Biologia Molecular de Barcelona/CSIC, Parc Científic de Barcelona, 08028 Barcelona, Spain
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48
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Bruckner FP, Xavier ADS, Cascardo RDS, Otoni WC, Zerbini FM, Alfenas‐Zerbini P. Translationally controlled tumour protein (TCTP) from tomato and Nicotiana benthamiana is necessary for successful infection by a potyvirus. MOLECULAR PLANT PATHOLOGY 2017; 18:672-683. [PMID: 27159273 PMCID: PMC6638207 DOI: 10.1111/mpp.12426] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 05/02/2016] [Accepted: 05/05/2016] [Indexed: 05/20/2023]
Abstract
Translationally controlled tumour protein (TCTP) is a ubiquitously distributed protein in eukaryotes, involved in the regulation of several processes, including cell cycle progression, cell growth, stress protection, apoptosis and maintenance of genomic integrity. Its expression is induced during the early stages of tomato (Solanum lycopersicum) infection by the potyvirus Pepper yellow mosaic virus (PepYMV, a close relative of Potato virus Y). Tomato TCTP is a protein of 168 amino acids, which contains all the conserved domains of the TCTP family. To study the effects of TCTP silencing in PepYMV infection, Nicotiana benthamiana plants were silenced by virus-induced gene silencing (VIGS) and transgenic tomato plants silenced for TCTP were obtained. In the early stages of infection, both tomato and N. benthamiana silenced plants accumulated less virus than control plants. Transgenic tomato plants showed a drastic reduction in symptoms and no viral accumulation at 14 days post-inoculation. Subcellular localization of TCTP was determined in healthy and systemically infected N. benthamiana leaves. TCTP was observed in both the nuclei and cytoplasm of non-infected cells, but only in the cytoplasm of infected cells. Our results indicate that TCTP is a growth regulator necessary for successful PepYMV infection and that its localization is altered by the virus, probably to favour the establishment of virus infection. A network with putative interactions that may occur between TCTP and Arabidopsis thaliana proteins was built. This network brings together experimental data of interactions that occur in other eukaryotes and helps us to discuss the possibilities of TCTP involvement in viral infection.
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Affiliation(s)
- Fernanda Prieto Bruckner
- Departamento de Microbiologia/BIOAGRO/National Institute of Science and Technology in Plant‐Pest InteractionsUniversidade Federal de ViçosaViçosaMG36570‐900Brazil
| | - André Da Silva Xavier
- Departamento de Fitopatologia/BIOAGRO/National Institute of Science and Technology in Plant‐Pest InteractionsUniversidade Federal de ViçosaViçosaMG36570‐900Brazil
| | - Renan De Souza Cascardo
- Departamento de Microbiologia/BIOAGRO/National Institute of Science and Technology in Plant‐Pest InteractionsUniversidade Federal de ViçosaViçosaMG36570‐900Brazil
| | - Wagner Campos Otoni
- Departamento de Biologia Vegetal/BIOAGROUniversidade Federal de ViçosaViçosaMG36570‐900Brazil
| | - Francisco Murilo Zerbini
- Departamento de Fitopatologia/BIOAGRO/National Institute of Science and Technology in Plant‐Pest InteractionsUniversidade Federal de ViçosaViçosaMG36570‐900Brazil
| | - Poliane Alfenas‐Zerbini
- Departamento de Microbiologia/BIOAGRO/National Institute of Science and Technology in Plant‐Pest InteractionsUniversidade Federal de ViçosaViçosaMG36570‐900Brazil
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49
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Bastet A, Robaglia C, Gallois JL. eIF4E Resistance: Natural Variation Should Guide Gene Editing. TRENDS IN PLANT SCIENCE 2017; 22:411-419. [PMID: 28258958 DOI: 10.1016/j.tplants.2017.01.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/20/2017] [Accepted: 01/31/2017] [Indexed: 05/19/2023]
Abstract
eIF4E translation initiation factors have emerged as major susceptibility factors for RNA viruses. Natural eIF4E-based resistance alleles are found in many species and are mostly variants that maintain the translation function of the protein. eIF4E genes represent major targets for engineering viral resistance, and gene-editing technologies can be used to make up for the lack of natural resistance alleles in some crops, often by knocking out eIF4E susceptibility factors. However, we report here how redundancy among eIF4E genes can restrict the efficient use of knockout alleles in breeding. We therefore discuss how gene-editing technologies can be used to design de novo functional alleles, using knowledge about the natural evolution of eIF4E genes in different species, to drive resistance to viruses without affecting plant physiology.
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Affiliation(s)
- Anna Bastet
- GAFL, INRA, 84140, Montfavet, France; Aix Marseille University, Biologie Végétale et Microbiologie Environnementales UMR 7265, Laboratoire de Génétique et Biophysique des Plantes, Marseille F-13009, France; CNRS, UMR 7265 Biologie Végétale et Microbiologie Environnementales, Marseille F-13009, France; CEA, Bioscience and Biotechnology Institute of Aix-Marseille, Marseille F-13009, France
| | - Christophe Robaglia
- Aix Marseille University, Biologie Végétale et Microbiologie Environnementales UMR 7265, Laboratoire de Génétique et Biophysique des Plantes, Marseille F-13009, France; CNRS, UMR 7265 Biologie Végétale et Microbiologie Environnementales, Marseille F-13009, France; CEA, Bioscience and Biotechnology Institute of Aix-Marseille, Marseille F-13009, France
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50
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Machado JPB, Calil IP, Santos AA, Fontes EPB. Translational control in plant antiviral immunity. Genet Mol Biol 2017; 40:292-304. [PMID: 28199446 PMCID: PMC5452134 DOI: 10.1590/1678-4685-gmb-2016-0092] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 09/27/2016] [Indexed: 01/11/2023] Open
Abstract
Due to the limited coding capacity of viral genomes, plant viruses depend extensively on the host cell machinery to support the viral life cycle and, thereby, interact with a large number of host proteins during infection. Within this context, as plant viruses do not harbor translation-required components, they have developed several strategies to subvert the host protein synthesis machinery to produce rapidly and efficiently the viral proteins. As a countermeasure against infection, plants have evolved defense mechanisms that impair viral infections. Among them, the host-mediated translational suppression has been characterized as an efficient mean to restrict infection. To specifically suppress translation of viral mRNAs, plants can deploy susceptible recessive resistance genes, which encode translation initiation factors from the eIF4E and eIF4G family and are required for viral mRNA translation and multiplication. Additionally, recent evidence has demonstrated that, alternatively to the cleavage of viral RNA targets, host cells can suppress viral protein translation to silence viral RNA. Finally, a novel strategy of plant antiviral defense based on suppression of host global translation, which is mediated by the transmembrane immune receptor NIK1 (nuclear shuttle protein (NSP)-Interacting Kinase1), is discussed in this review.
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Affiliation(s)
- João Paulo B Machado
- Department of Biochemistry and Molecular Biology, BIOAGRO, National Institute of Science and Technology in Plant-Pest Interactions, Universidade Federal de Viçosa, 36571.000, Viçosa, MG, Brazil
| | - Iara P Calil
- Department of Biochemistry and Molecular Biology, BIOAGRO, National Institute of Science and Technology in Plant-Pest Interactions, Universidade Federal de Viçosa, 36571.000, Viçosa, MG, Brazil
| | - Anésia A Santos
- Department of General Biology, Universidade Federal de Viçosa, 36571.000, Viçosa, MG, Brazil
| | - Elizabeth P B Fontes
- Department of Biochemistry and Molecular Biology, BIOAGRO, National Institute of Science and Technology in Plant-Pest Interactions, Universidade Federal de Viçosa, 36571.000, Viçosa, MG, Brazil
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