1
|
Bunyaviral N Proteins Localize at RNA Processing Bodies and Stress Granules: The Enigma of Cytoplasmic Sources of Capped RNA for Cap Snatching. Viruses 2022; 14:v14081679. [PMID: 36016301 PMCID: PMC9414089 DOI: 10.3390/v14081679] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/18/2022] [Accepted: 07/26/2022] [Indexed: 11/17/2022] Open
Abstract
Most cytoplasmic-replicating negative-strand RNA viruses (NSVs) initiate genome transcription by cap snatching. The source of host mRNAs from which the cytoplasmic NSVs snatch capped-RNA leader sequences has remained elusive. Earlier reports have pointed towards cytoplasmic-RNA processing bodies (P body, PB), although several questions have remained unsolved. Here, the nucleocapsid (N) protein of plant- and animal-infecting members of the order Bunyavirales, in casu Tomato spotted wilt virus (TSWV), Rice stripe virus (RSV), Sin nombre virus (SNV), Crimean-Congo hemorrhagic fever virus (CCHFV) and Schmallenberg virus (SBV) have been expressed and localized in cells of their respective plant and animal hosts. All N proteins localized to PBs as well as stress granules (SGs), but extensively to docking stages of PB and SG. TSWV and RSV N proteins also co-localized with Ran GTPase-activating protein 2 (RanGAP2), a nucleo-cytoplasmic shuttling factor, in the perinuclear region, and partly in the nucleus when co-expressed with its WPP domain containing a nuclear-localization signal. Upon silencing of PB and SG components individually or concomitantly, replication levels of a TSWV minireplicon, as measured by the expression of a GFP reporter gene, ranged from a 30% reduction to a four-fold increase. Upon the silencing of RanGAP homologs in planta, replication of the TSWV minireplicon was reduced by 75%. During in vivo cap-donor competition experiments, TSWV used transcripts destined to PB and SG, but also functional transcripts engaged in translation. Altogether, the results implicate a more complex situation in which, besides PB, additional cytoplasmic sources are used during transcription/cap snatching of cytoplasmic-replicating and segmented NSVs.
Collapse
|
2
|
Molecular Characteristics and Incidence of Apple Rubbery Wood Virus 2 and Citrus Virus A Infecting Pear Trees in China. Viruses 2022; 14:v14030576. [PMID: 35336983 PMCID: PMC8952854 DOI: 10.3390/v14030576] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/28/2022] [Accepted: 03/05/2022] [Indexed: 02/05/2023] Open
Abstract
Apple rubbery wood virus 2 (ARWV-2) and citrus virus A (CiVA) belong to a recently approved family Phenuiviridae in the order Bunyavirales and possess negative-sense single-stranded RNA genomes. In this study, the genome sequence of three ARWV-2 isolates (S17E2, LYC2, and LYXS) and a CiVA isolate (CiVA-P) infecting pear trees grown in China were characterized using high-throughput sequencing combined with conventional reverse-transcription PCR (RT-PCR) assays. The genome-wide nt sequence identities were above 93.6% among the ARWV-2 isolates and above 93% among CiVA isolates. Sequence comparisons showed that sequence diversity occurred in the 5′ untranslated region of the ARWV-2 genome and the intergenic region of the CiVA genome. For the first time, this study revealed that ARWV-2 proteins Ma and Mb displayed a plasmodesma subcellular localization, and the MP of CiVA locates in cell periphery and can interact with the viral NP in bimolecular fluorescence complementation assays. RT-PCR tests disclosed that ARWV-2 widely occurs, while CiVA has a low incidence in pear trees grown in China. This study presents the first complete genome sequences and incidences of ARWV-2 and CiVA from pear trees and the obtained results extend our knowledge of the viral pathogens of pear grown in China.
Collapse
|
3
|
Borges Naito FY, Widana Gamage SMK, Mitter N, Dietzgen RG. Temporal expression of defence and susceptibility genes and tospovirus accumulation in capsicum chlorosis virus-infected capsicum. Arch Virol 2022; 167:1061-1074. [PMID: 35246732 PMCID: PMC8964570 DOI: 10.1007/s00705-022-05401-1] [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: 12/09/2021] [Accepted: 02/09/2022] [Indexed: 11/25/2022]
Abstract
Yolo Wonder (YW) and Warlock (W), two capsicum cultivars that are susceptible to capsicum chlorosis virus (CaCV), were compared in terms of symptom development, tospovirus accumulation, and host gene expression during the first 12 days post infection (dpi). Temporal expression of selected early CaCV-response genes was used to gain insights into plant-virus interactions and to identify potential targets for CaCV control. Symptoms developed faster in YW during the first seven days of infection, while systemic symptoms were similar in both cultivars at 10 and 12 dpi. CaCV accumulation was higher in YW at 7 dpi despite a lower titre at 3 dpi. At 12 dpi, virus accumulation was similar for both cultivars. Symptom development appears to be correlated to virus accumulation over time for both cultivars. Chalcone synthase (CHS), cytochrome P450 (CYP), and tetraspanin 8-like (TSP8) genes followed a similar expression pattern over time in both cultivars. The thionin gene showed increased expression in CaCV-infected plants at 12 dpi. The WRKY40 gene showed significant differential expression at all time points in YW, but only at 12 dpi in W. The strongest correlation of temporal gene expression and virus titre was seen for CYP, TSP8, thionin, and WRKY40. CHS and CYP may be involved in symptom development, and TSP8 may be involved in virus movement. CHS, CYP, and TSP8 may be good targets for future overexpression or silencing studies to clarify their functions during virus infection and, potentially, for control of CaCV in capsicum.
Collapse
Affiliation(s)
- Fernanda Yuri Borges Naito
- Queensland Alliance for Agriculture and Food Innovation, Centre for Horticultural Science, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | | | - Neena Mitter
- Queensland Alliance for Agriculture and Food Innovation, Centre for Horticultural Science, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Ralf Georg Dietzgen
- Queensland Alliance for Agriculture and Food Innovation, Centre for Horticultural Science, The University of Queensland, St. Lucia, QLD, 4072, Australia.
| |
Collapse
|
4
|
Wang Y, Wang G, Bai J, Zhang Y, Wang Y, Wen S, Li L, Yang Z, Hong N. A novel Actinidia cytorhabdovirus characterized using genomic and viral protein interaction features. MOLECULAR PLANT PATHOLOGY 2021; 22:1271-1287. [PMID: 34288324 PMCID: PMC8435229 DOI: 10.1111/mpp.13110] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
A novel cytorhabdovirus, tentatively named Actinidia virus D (AcVD), was identified from kiwifruit (Actinidia chinensis) in China using high-throughput sequencing technology. The genome of AcVD consists of 13,589 nucleotides and is organized into seven open reading frames (ORFs) in its antisense strand, coding for proteins in the order N-P-P3-M-G-P6-L. The ORFs were flanked by a 3' leader sequence and a 5' trailer sequence and are separated by conserved intergenic junctions. The genome sequence of AcVD was 44.6%-51.5% identical to those of reported cytorhabdoviruses. The proteins encoded by AcVD shared the highest sequence identities, ranging from 27.3% (P6) to 44.5% (L), with the respective proteins encoded by reported cytorhabdoviruses. Phylogenetic analysis revealed that AcVD clustered together with the cytorhabdovirus Wuhan insect virus 4. The subcellular locations of the viral proteins N, P, P3, M, G, and P6 in epidermal cells of Nicotiana benthamiana leaves were determined. The M protein of AcVD uniquely formed filament structures and was associated with microtubules. Bimolecular fluorescence complementation assays showed that three proteins, N, P, and M, self-interact, protein N plays a role in the formation of cytoplasm viroplasm, and protein M recruits N, P, P3, and G to microtubules. In addition, numerous paired proteins interact in the nucleus. This study presents the first evidence of a cytorhabdovirus infecting kiwifruit plants and full location and interaction maps to gain insight into viral protein functions.
Collapse
Affiliation(s)
- Yanxiang Wang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Horticultural Crop (Fruit Trees) Biology and Germplasm Creation of the Ministry of AgricultureHuazhong Agricultural UniversityWuhanChina
| | - Guoping Wang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Horticultural Crop (Fruit Trees) Biology and Germplasm Creation of the Ministry of AgricultureHuazhong Agricultural UniversityWuhanChina
| | - Jianyu Bai
- Laboratory of Fruit Trees DiseaseInstitute of Economic ForestryXinjiang Academy of Forestry SciencesUrumqiChina
| | - Yongle Zhang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Ying Wang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Shaohua Wen
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Liu Li
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Zuokun Yang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Ni Hong
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Horticultural Crop (Fruit Trees) Biology and Germplasm Creation of the Ministry of AgricultureHuazhong Agricultural UniversityWuhanChina
| |
Collapse
|
5
|
Kormelink R, Verchot J, Tao X, Desbiez C. The Bunyavirales: The Plant-Infecting Counterparts. Viruses 2021; 13:v13050842. [PMID: 34066457 PMCID: PMC8148189 DOI: 10.3390/v13050842] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/26/2021] [Accepted: 04/29/2021] [Indexed: 12/18/2022] Open
Abstract
Negative-strand (-) RNA viruses (NSVs) comprise a large and diverse group of viruses that are generally divided in those with non-segmented and those with segmented genomes. Whereas most NSVs infect animals and humans, the smaller group of the plant-infecting counterparts is expanding, with many causing devastating diseases worldwide, affecting a large number of major bulk and high-value food crops. In 2018, the taxonomy of segmented NSVs faced a major reorganization with the establishment of the order Bunyavirales. This article overviews the major plant viruses that are part of the order, i.e., orthospoviruses (Tospoviridae), tenuiviruses (Phenuiviridae), and emaraviruses (Fimoviridae), and provides updates on the more recent ongoing research. Features shared with the animal-infecting counterparts are mentioned, however, special attention is given to their adaptation to plant hosts and vector transmission, including intra/intercellular trafficking and viral counter defense to antiviral RNAi.
Collapse
Affiliation(s)
- Richard Kormelink
- Laboratory of Virology, Department of Plant Sciences, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Jeanmarie Verchot
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843, USA
| | - Xiaorong Tao
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
| | | |
Collapse
|
6
|
Iswanto ABB, Shelake RM, Vu MH, Kim JY, Kim SH. Genome Editing for Plasmodesmal Biology. FRONTIERS IN PLANT SCIENCE 2021; 12:679140. [PMID: 34149780 PMCID: PMC8207191 DOI: 10.3389/fpls.2021.679140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 05/10/2021] [Indexed: 05/08/2023]
Abstract
Plasmodesmata (PD) are cytoplasmic canals that facilitate intercellular communication and molecular exchange between adjacent plant cells. PD-associated proteins are considered as one of the foremost factors in regulating PD function that is critical for plant development and stress responses. Although its potential to be used for crop engineering is enormous, our understanding of PD biology was relatively limited to model plants, demanding further studies in crop systems. Recently developed genome editing techniques such as Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associate protein (CRISPR/Cas) might confer powerful approaches to dissect the molecular function of PD components and to engineer elite crops. Here, we assess several aspects of PD functioning to underline and highlight the potential applications of CRISPR/Cas that provide new insight into PD biology and crop improvement.
Collapse
Affiliation(s)
- Arya Bagus Boedi Iswanto
- Division of Applied Life Sciences (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea
| | - Rahul Mahadev Shelake
- Division of Applied Life Sciences (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea
| | - Minh Huy Vu
- Division of Applied Life Sciences (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea
| | - Jae-Yean Kim
- Division of Applied Life Sciences (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea
- Division of Applied Life Sciences, Gyeongsang National University, Jinju, South Korea
- Jae-Yean Kim,
| | - Sang Hee Kim
- Division of Applied Life Sciences (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, South Korea
- Division of Applied Life Sciences, Gyeongsang National University, Jinju, South Korea
- *Correspondence: Sang Hee Kim,
| |
Collapse
|
7
|
Huang CH, Foo MH, Raja JAJ, Tan YR, Lin TT, Lin SS, Yeh SD. A Conserved Helix in the C-Terminal Region of Watermelon Silver Mottle Virus Nonstructural Protein S Is Imperative For Protein Stability Affecting Self-Interaction, RNA Silencing Suppression, and Pathogenicity. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:637-652. [PMID: 31935338 DOI: 10.1094/mpmi-10-19-0279-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In orthotospovirus, the nonstructural protein S (NSs) is the RNA-silencing suppressor (RSS) and pathogenicity determinant. Here, we demonstrate that a putative α-helix, designated H8, spanning amino acids 338 to 369 of the C-terminal region of the NSs protein, is crucial for self-interaction of watermelon silver mottle virus NSs protein and that the H8 affects RSS function. Co-immunoprecipitation, yeast two-hybrid, and bimolecular fluorescence complementation analyses revealed that the triple point mutation (TPM) of H8 amino acids Y338A, H350A, and F353A resulted in NSs protein self-interaction dysfunction. Transient expression of H8-deleted (ΔH8) and TPM NSs proteins in Nicotiana benthamiana plants by agroinfitration indicated that these proteins have weaker RSS activity and are far less stable than wild-type (WT) NSs. However, an electrophoretic mobility assay revealed that small interfering RNA (siRNA) binding ability of TPM NSs protein is not compromised. The pathogenicity assay of WT NSs protein expressed by the attenuated turnip mosaic virus vector restored severe symptoms in recombinant-infected N. benthamiana plants but not for ΔH8 or TPM proteins. Taken together, we conclude that the H8 helix in the C-terminal region of NSs protein is crucial for stabilizing NSs protein through self-interaction to maintain normal functions of RSS and pathogenicity, but not for NSs-siRNA binding activity.
Collapse
Affiliation(s)
- Chung-Hao Huang
- Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan, Republic of China
- Advanced Plant Biotechnology Center, National Chung Hsing University
| | - Mung-Hsia Foo
- Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan, Republic of China
| | - Joseph A J Raja
- Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan, Republic of China
- Advanced Plant Biotechnology Center, National Chung Hsing University
| | - Yue-Rong Tan
- Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan, Republic of China
| | - Tzu-Tung Lin
- Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan, Republic of China
| | - Shih-Shun Lin
- Advanced Plant Biotechnology Center, National Chung Hsing University
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan, Republic of China
| | - Shyi-Dong Yeh
- Department of Plant Pathology, National Chung Hsing University, Taichung 40227, Taiwan, Republic of China
- Advanced Plant Biotechnology Center, National Chung Hsing University
| |
Collapse
|
8
|
Hunter K, Kimura S, Rokka A, Tran HC, Toyota M, Kukkonen JP, Wrzaczek M. CRK2 Enhances Salt Tolerance by Regulating Callose Deposition in Connection with PLD α1. PLANT PHYSIOLOGY 2019; 180:2004-2021. [PMID: 31118265 PMCID: PMC6670071 DOI: 10.1104/pp.19.00560] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 05/15/2019] [Indexed: 05/03/2023]
Abstract
High salinity is an increasingly prevalent source of stress to which plants must adapt. The receptor-like protein kinases, including members of the Cys-rich receptor-like kinase (CRK) subfamily, are a highly expanded family of transmembrane proteins in plants that are largely responsible for communication between cells and the extracellular environment. Various CRKs have been implicated in biotic and abiotic stress responses; however, their functions on a cellular level remain largely uncharacterized. Here we have shown that CRK2 enhances salt tolerance at the germination stage in Arabidopsis (Arabidopsis thaliana) and also modulates root length. We established that functional CRK2 is required for salt-induced callose deposition. In doing so, we revealed a role for callose deposition in response to increased salinity and demonstrated its importance for salt tolerance during germination. Using fluorescently tagged proteins, we observed specific changes in the subcellular localization of CRK2 in response to various stress treatments. Many of CRK2's cellular functions were dependent on phospholipase D activity, as were the subcellular localization changes. Thus, we propose that CRK2 acts downstream of phospholipase D during salt stress, promoting callose deposition and regulating plasmodesmal permeability, and that CRK2 adopts specific stress-dependent subcellular localization patterns that allow it to carry out its functions.
Collapse
Affiliation(s)
- Kerri Hunter
- Viikki Plant Science Centre, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Sachie Kimura
- Viikki Plant Science Centre, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Anne Rokka
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland
| | - Huy Cuong Tran
- Viikki Plant Science Centre, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Masatsugu Toyota
- Department of Biochemistry and Molecular Biology, Saitama University, Saitama, Japan
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jyrki P Kukkonen
- Biochemistry and Cell Biology, Department of Veterinary Biosciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Michael Wrzaczek
- Viikki Plant Science Centre, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| |
Collapse
|
9
|
Zhou X, Lin W, Sun K, Wang S, Zhou X, Jackson AO, Li Z. Specificity of Plant Rhabdovirus Cell-to-Cell Movement. J Virol 2019; 93:e00296-19. [PMID: 31118256 PMCID: PMC6639277 DOI: 10.1128/jvi.00296-19] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/15/2019] [Indexed: 12/13/2022] Open
Abstract
Positive-stranded RNA virus movement proteins (MPs) generally lack sequence-specific nucleic acid-binding activities and display cross-family movement complementarity with related and unrelated viruses. Negative-stranded RNA plant rhabdoviruses encode MPs with limited structural and functional relatedness with other plant virus counterparts, but the precise mechanisms of intercellular transport are obscure. In this study, we first analyzed the abilities of MPs encoded by five distinct rhabdoviruses to support cell-to-cell movement of two positive-stranded RNA viruses by using trans-complementation assays. Each of the five rhabdovirus MPs complemented the movement of MP-defective mutants of tomato mosaic virus and potato X virus. In contrast, movement of recombinant MP deletion mutants of sonchus yellow net nucleorhabdovirus (SYNV) and tomato yellow mottle-associated cytorhabdovirus (TYMaV) was rescued only by their corresponding MPs, i.e., SYNV sc4 and TYMaV P3. Subcellular fractionation analyses revealed that SYNV sc4 and TYMaV P3 were peripherally associated with cell membranes. A split-ubiquitin membrane yeast two-hybrid assay demonstrated specific interactions of the membrane-associated rhabdovirus MPs only with their cognate nucleoproteins (N) and phosphoproteins (P). More importantly, SYNV sc4-N and sc4-P interactions directed a proportion of the N-P complexes from nuclear sites of replication to punctate loci at the cell periphery that partially colocalized with the plasmodesmata. Our data show that cell-to-cell movement of plant rhabdoviruses is highly specific and suggest that cognate MP-nucleocapsid core protein interactions are required for intra- and intercellular trafficking.IMPORTANCE Local transport of plant rhabdoviruses likely involves the passage of viral nucleocapsids through MP-gated plasmodesmata, but the molecular mechanisms are not fully understood. We have conducted complementation assays with MPs encoded by five distinct rhabdoviruses to assess their movement specificity. Each of the rhabdovirus MPs complemented the movement of MP-defective mutants of two positive-stranded RNA viruses that have different movement strategies. In marked contrast, cell-to-cell movement of two recombinant plant rhabdoviruses was highly specific in requiring their cognate MPs. We have shown that these rhabdovirus MPs are localized to the cell periphery and associate with cellular membranes, and that they interact only with their cognate nucleocapsid core proteins. These interactions are able to redirect viral nucleocapsid core proteins from their sites of replication to the cell periphery. Our study provides a model for the specific inter- and intracellular trafficking of plant rhabdoviruses that may be applicable to other negative-stranded RNA viruses.
Collapse
Affiliation(s)
- Xin Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Wenye Lin
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Kai Sun
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Shuo Wang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Xueping Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Andrew O Jackson
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, USA
| | - Zhenghe Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Zhejiang University, Hangzhou, China
| |
Collapse
|
10
|
Duan Z, Xu H, Ji X, Zhao J, Xu H, Hu Y, Deng S, Hu S, Liu X. Importin α5 negatively regulates importin β1-mediated nuclear import of Newcastle disease virus matrix protein and viral replication and pathogenicity in chicken fibroblasts. Virulence 2018. [PMID: 29532715 PMCID: PMC5955436 DOI: 10.1080/21505594.2018.1449507] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The matrix (M) protein of Newcastle disease virus (NDV) is demonstrated to localize in the nucleus via intrinsic nuclear localization signal (NLS), but cellular proteins involved in the nuclear import of NDV M protein and the role of M's nuclear localization in the replication and pathogenicity of NDV remain unclear. In this study, importin β1 was screened to interact with NDV M protein by yeast two-hybrid screening. This interaction was subsequently confirmed by co-immunoprecipitation and pull-down assays. In vitro binding studies indicated that the NLS region of M protein and the amino acids 336–433 of importin β1 that belonged to the RanGTP binding region were important for binding. Importantly, a recombinant virus with M/NLS mutation resulted in a pathotype change of NDV and attenuated viral replication and pathogenicity in chicken fibroblasts and SPF chickens. In agreement with the binding data, nuclear import of NDV M protein in digitonin-permeabilized HeLa cells required both importin β1 and RanGTP. Interestingly, importin α5 was verified to interact with M protein through binding importin β1. However, importin β1 or importin α5 depletion by siRNA resulted in different results, which showed the obviously cytoplasmic or nuclear accumulation of M protein and the remarkably decreased or increased replication ability and pathogenicity of NDV in chicken fibroblasts, respectively. Our findings therefore demonstrate for the first time the nuclear import mechanism of NDV M protein and the negative regulation role of importin α5 in importin β1-mediated nuclear import of M protein and the replication and pathogenicity of a paramyxovirus.
Collapse
Affiliation(s)
- Zhiqiang Duan
- a Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education , Guizhou University , Guiyang , China.,b College of Animal Science , Guizhou University , Guiyang , China
| | - Haixu Xu
- c Key Laboratory of Animal Infectious Diseases of Ministry of Agriculture , Yangzhou University , Yangzhou , China
| | - Xinqin Ji
- a Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education , Guizhou University , Guiyang , China.,b College of Animal Science , Guizhou University , Guiyang , China
| | - Jiafu Zhao
- a Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education , Guizhou University , Guiyang , China.,b College of Animal Science , Guizhou University , Guiyang , China
| | - Houqiang Xu
- a Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education , Guizhou University , Guiyang , China.,b College of Animal Science , Guizhou University , Guiyang , China
| | - Yan Hu
- b College of Animal Science , Guizhou University , Guiyang , China
| | - Shanshan Deng
- b College of Animal Science , Guizhou University , Guiyang , China
| | - Shunlin Hu
- c Key Laboratory of Animal Infectious Diseases of Ministry of Agriculture , Yangzhou University , Yangzhou , China
| | - Xiufan Liu
- c Key Laboratory of Animal Infectious Diseases of Ministry of Agriculture , Yangzhou University , Yangzhou , China
| |
Collapse
|
11
|
Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant. Viruses 2018. [PMID: 29538326 PMCID: PMC5869522 DOI: 10.3390/v10030129] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Plant viruses are inducers and targets of antiviral RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressor proteins that interfere with antiviral RNA silencing. The NSs protein is an RNA silencing suppressor in orthotospoviruses, such as the tomato spotted wilt virus (TSWV). The mechanism of RNA silencing suppression by NSs and its role in virus infection and movement are poorly understood. Here, we cloned and tagged TSWV NSs and expressed it from a GFP-tagged turnip mosaic virus (TuMV-GFP) carrying either a wild-type or suppressor-deficient (AS9) helper component proteinase (HC-Pro). When expressed in cis, NSs restored pathogenicity and promoted systemic infection of suppressor-deficient TuMV-AS9-GFP in Nicotiana benthamiana and Arabidopsis thaliana. Inactivating mutations were introduced in NSs RNA-binding domain one. A genetic analysis with active and suppressor-deficient NSs, in combination with wild-type and mutant plants lacking essential components of the RNA silencing machinery, showed that the NSs insert is stable when expressed from a potyvirus. NSs can functionally replace potyviral HC-Pro, condition virus susceptibility, and promote systemic infection and symptom development by suppressing antiviral RNA silencing through a mechanism that partially overlaps that of potyviral HC-Pro. The results presented provide new insight into the mechanism of silencing suppression by NSs and its effect on virus infection.
Collapse
|
12
|
Atabekova AK, Lazareva EA, Strelkova OS, Solovyev AG, Morozov SY. Mechanical stress-induced subcellular re-localization of N-terminally truncated tobacco Nt-4/1 protein. Biochimie 2018; 144:98-107. [PMID: 29097279 DOI: 10.1016/j.biochi.2017.10.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 10/25/2017] [Indexed: 01/22/2023]
Abstract
The Nicotiana tabacum 4/1 protein (Nt-4/1) of unknown function expressed in plant vasculature has been shown to localize to cytoplasmic bodies associated with endoplasmic reticulum. Here, we analyzed molecular interactions of an Nt-4/1 mutant with a deletion of 90 N-terminal amino acid residues (Nt-4/1d90) having a diffuse GFP-like localization. Upon transient co-expression with VAP27, a membrane protein known to localize to the ER, ER-plasma membrane contact sites and plasmodesmata, Nt-4/1d90 was concentrated around the cortical ER tubules, forming a network matching the shape of the cortical ER. Additionally, in response to mechanical stress, Nt-4/1d90 was re-localized to small spherical bodies, whereas the subcellular localization of VAP27 remained essentially unaffected. The Nt-4/1d90-containing bodies associated with microtubules, which underwent noticeable bundling under the conditions of mechanical stress. The Nt-4/1d90 re-localization to spherical bodies could also be induced by incubation at an elevated temperature, although under heat shock conditions the re-localization was less efficient and incomplete. An Nt-4/1d90 mutant, which had phosphorylation-mimicking mutations in a predicted cluster of four potentially phosphorylated residues, was found to both inefficiently re-localize to spherical bodies and tend to revert back to the initial diffuse localization. The presented data show that Nt-4/1 has a potential for response to stresses that is manifested by its deletion mutant Nt-4/1d90, and this response can be mediated by protein dephosphorylation.
Collapse
Affiliation(s)
- Anastasia K Atabekova
- Department of Virology, Biological Faculty, Moscow State University, Moscow 119234, Russia
| | - Ekaterina A Lazareva
- Department of Virology, Biological Faculty, Moscow State University, Moscow 119234, Russia
| | - Olga S Strelkova
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119992, Russia
| | - Andrey G Solovyev
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119992, Russia; Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Moscow 119991, Russia
| | - Sergey Y Morozov
- Department of Virology, Biological Faculty, Moscow State University, Moscow 119234, Russia; Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119992, Russia.
| |
Collapse
|