1
|
Lee S, Seo YE, Choi J, Yan X, Kim T, Choi D, Lee JH. Nucleolar actions in plant development and stress responses. PLANT, CELL & ENVIRONMENT 2024. [PMID: 39169813 DOI: 10.1111/pce.15099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 08/09/2024] [Accepted: 08/10/2024] [Indexed: 08/23/2024]
Abstract
The nucleolus is conventionally acknowledged for its role in ribosomal RNA (rRNA) synthesis and ribosome biogenesis. Recent research has revealed its multifaceted involvement in plant biology, encompassing regulation of the cell cycle, development, and responses to environmental stresses. This comprehensive review explores the diverse roles of the nucleolus in plant growth and responses to environmental stresses. The introduction delves into its traditional functions in rRNA synthesis and potential participation in nuclear liquid-liquid phase separation. By examining the multifaceted roles of nucleolar proteins in plant development, we highlight the impacts of various nucleolar mutants on growth, development, and embryogenesis. Additionally, we reviewed the involvement of nucleoli in responses to abiotic and biotic stresses. Under abiotic stress conditions, the nucleolar structure undergoes morphological changes. In the context of biotic stress, the nucleolus emerges as a common target for effectors of pathogens for manipulation of host immunity to enhance pathogenicity. The detailed exploration of how pathogens interact with nucleoli and manipulate host responses provides valuable insights into plant stress responses as well as plant growth and development. Understanding these processes may pave the way for promising strategies to enhance crop resilience and mitigate the impact of biotic and abiotic stresses in agricultural systems.
Collapse
Affiliation(s)
- Soeui Lee
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| | - Ye-Eun Seo
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Plant Genomics and Breeding Institute, Seoul National University, Seoul, South Korea
| | - Jeen Choi
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Plant Genomics and Breeding Institute, Seoul National University, Seoul, South Korea
| | - Xin Yan
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Plant Genomics and Breeding Institute, Seoul National University, Seoul, South Korea
| | - Taewon Kim
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Plant Genomics and Breeding Institute, Seoul National University, Seoul, South Korea
| | - Doil Choi
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
- Department of Agriculture, Forestry and Bioresources, College of Agriculture and Life Science, Plant Genomics and Breeding Institute, Seoul National University, Seoul, South Korea
| | - Joo Hyun Lee
- Plant Immunity Research Center, Seoul National University, Seoul, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| |
Collapse
|
2
|
Ranty-Roby S, Pontvianne F, Quentin M, Favery B. The overlooked manipulation of nucleolar functions by plant pathogen effectors. FRONTIERS IN PLANT SCIENCE 2024; 15:1445097. [PMID: 39175483 PMCID: PMC11339880 DOI: 10.3389/fpls.2024.1445097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Accepted: 07/16/2024] [Indexed: 08/24/2024]
Abstract
Pathogens need to manipulate plant functions to facilitate the invasion of their hosts. They do this by secreting a cocktail of molecules called effectors. Studies of these molecules have mostly focused on the mechanisms underlying their recognition and the subsequent transcriptional reprogramming of cells, particularly in the case of R gene-dependent resistance. However, the roles of these effectors are complex, as they target all cell compartments and their plant targets remain largely uncharacterized. An understanding of the mechanisms involved would be a considerable asset for plant breeding. The nucleolus is the site of many key cellular functions, such as ribosome biogenesis, cellular stress regulation and many other functions that could be targets for pathogenicity. However, little attention has been paid to effectors targeting nucleolar functions. In this review, we aim to fill this gap by providing recent findings on pathogen effectors that target and manipulate nucleolar functions and dynamics to promote infection. In particular, we look at how some effectors hijack ribosome biogenesis, the modulation of transcription or alternative splicing, all key functions occurring at least partially in the nucleolus. By shedding light on the role of the plant nucleolus in pathogen interactions, this review highlights the importance of understanding nucleolar biology in the context of plant immunity and the mechanisms manipulated by plant pathogens.
Collapse
Affiliation(s)
- Sarah Ranty-Roby
- INRAE, Université Côte d’Azur, CNRS, Institut Sophia Agrobiotech (ISA), Sophia Antipolis F-06903, Sophia Antipolis, France
| | | | - Michaël Quentin
- INRAE, Université Côte d’Azur, CNRS, Institut Sophia Agrobiotech (ISA), Sophia Antipolis F-06903, Sophia Antipolis, France
| | - Bruno Favery
- INRAE, Université Côte d’Azur, CNRS, Institut Sophia Agrobiotech (ISA), Sophia Antipolis F-06903, Sophia Antipolis, France
- International Research Organization for Advanced Science and Technology, Kumamoto University, Kumamoto, Japan
| |
Collapse
|
3
|
Leastro MO, Pallás V, Sánchez-Navarro JÁ. The capsid protein of citrus leprosis virus C shows a nuclear distribution and interacts with the nucleolar fibrillarin protein. Virus Res 2024; 340:199297. [PMID: 38070688 PMCID: PMC10758971 DOI: 10.1016/j.virusres.2023.199297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/29/2023] [Accepted: 12/06/2023] [Indexed: 01/05/2024]
Abstract
Brevipalpus-transmitted viruses (BTVs) have a significant negative economic impact on the citrus industry in Central and South America. Until now, only a few studies have explored the intracellular distribution and interaction of BTVs-encoded proteins with host factors, particularly for cileviruses, the main BTV responsible for the Citrus Leprosis (CL) disease. This study describes the nuclear localization of citrus leprosis virus C (CiLV-C) capsid protein (p29) and its interaction with the fibrillarin (Fib2) within the nucleolar compartment and cell cytoplasm. Our results, obtained by computer predictions and laser scanning confocal microscopy analyses, including colocalization and bimolecular fluorescence complementation (BiFC) approaches, revealed that a fraction of the p29 is localized in the nucleus and colocalizes with the Fib2 in both the nucleolus and cytosol. The nuclear localization of p29 correlated with a smaller nucleus size. Furthermore, co-immunoprecipitation (Co-IP) assays confirmed the interactions between p29 and Fib2. The implications of these findings for the functionalities of the cilevirus capsid protein are discussed.
Collapse
Affiliation(s)
- Mikhail Oliveira Leastro
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Valencia 46022, Spain.
| | - Vicente Pallás
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Valencia 46022, Spain
| | - Jesús Ángel Sánchez-Navarro
- Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Valencia 46022, Spain.
| |
Collapse
|
4
|
Sheshukova EV, Kamarova KA, Ershova NM, Komarova TV. Nicotiana benthamiana Methanol-Inducible Gene (MIG) 21 Encodes a Nucleolus-Localized Protein That Stimulates Viral Intercellular Transport and Downregulates Nuclear Import. PLANTS (BASEL, SWITZERLAND) 2024; 13:279. [PMID: 38256832 PMCID: PMC10819229 DOI: 10.3390/plants13020279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/04/2024] [Accepted: 01/15/2024] [Indexed: 01/24/2024]
Abstract
The mechanical damage of plant tissues leads to the activation of methanol production and its release into the atmosphere. The gaseous methanol or vapors emitted by the damaged plant induce resistance in neighboring intact plants to bacterial pathogens but create favorable conditions for viral infection spread. Among the Nicotiana benthamiana methanol-inducible genes (MIGs), most are associated with plant defense and intercellular transport. Here, we characterize NbMIG21, which encodes a 209 aa protein (NbMIG21p) that does not share any homology with annotated proteins. NbMIG21p was demonstrated to contain a nucleolus localization signal (NoLS). Colocalization studies with fibrillarin and coilin, nucleolus and Cajal body marker proteins, revealed that NbMIG21p is distributed among these subnuclear structures. Our results show that recombinant NbMIG21 possesses DNA-binding properties. Similar to a gaseous methanol effect, an increased NbMIG21 expression leads to downregulation of the nuclear import of proteins with nuclear localization signals (NLSs), as was demonstrated with the GFP-NLS model protein. Moreover, upregulated NbMIG21 expression facilitates tobacco mosaic virus (TMV) intercellular transport and reproduction. We identified an NbMIG21 promoter (PrMIG21) and showed that it is methanol sensitive; thus, the induction of NbMIG21 mRNA accumulation occurs at the level of transcription. Our findings suggest that methanol-activated NbMIG21 might participate in creating favorable conditions for viral reproduction and spread.
Collapse
Affiliation(s)
- Ekaterina V. Sheshukova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, 119991 Moscow, Russia; (E.V.S.); (K.A.K.); (N.M.E.)
| | - Kamila A. Kamarova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, 119991 Moscow, Russia; (E.V.S.); (K.A.K.); (N.M.E.)
| | - Natalia M. Ershova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, 119991 Moscow, Russia; (E.V.S.); (K.A.K.); (N.M.E.)
| | - Tatiana V. Komarova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, 119991 Moscow, Russia; (E.V.S.); (K.A.K.); (N.M.E.)
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| |
Collapse
|
5
|
Decle-Carrasco S, Rodríguez-Piña AL, Rodríguez-Zapata LC, Castano E. Current research on viral proteins that interact with fibrillarin. Mol Biol Rep 2023; 50:4631-4643. [PMID: 36928641 PMCID: PMC10018631 DOI: 10.1007/s11033-023-08343-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 02/15/2023] [Indexed: 03/18/2023]
Abstract
The nucleolus is a multifunctional nuclear domain primarily dedicated to ribosome biogenesis. Certain viruses developed strategies to manipulate host nucleolar proteins to facilitate their replication by modulating ribosomal RNA (rRNA) processing. This association interferes with nucleolar functions resulting in overactivation or arrest of ribosome biogenesis, induction or inhibition of apoptosis, and affecting stress response. The nucleolar protein fibrillarin (FBL) is an important target of some plant and animal viruses. FBL is an essential and highly conserved S-adenosyl methionine (SAM) dependent methyltransferase, capable of rRNA degradation by its intrinsically disordered region (IDR), the glycine/arginine-rich (GAR) domain. It forms a ribonucleoprotein complex that directs 2'-O-methylations in more than 100 sites of pre-rRNAs. It is involved in multiple cellular processes, including initiation of transcription, oncogenesis, and apoptosis, among others. The interaction with animal viruses, including human viruses, triggered its redistribution to the nucleoplasm and cytoplasm, interfering with its role in pre-rRNA processing. Viral-encoded proteins with IDRs as nucleocapsids, matrix, Tat protein, and even a viral snoRNA, can associate with FBL, forcing the nucleolar protein to undergo atypical functions. Here we review the molecular mechanisms employed by animal and human viruses to usurp FBL functions and the effect on cellular processes, particularly in ribosome biogenesis.
Collapse
Affiliation(s)
- Stefano Decle-Carrasco
- Unidad de Bioquímica y Biología Molecular de Plantas. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Alma Laura Rodríguez-Piña
- Unidad de Bioquímica y Biología Molecular de Plantas. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Luis Carlos Rodríguez-Zapata
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Enrique Castano
- Unidad de Bioquímica y Biología Molecular de Plantas. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México.
| |
Collapse
|
6
|
Londoño Vélez V, Alquraish F, Tarbiyyah I, Rafique F, Mao D, Chodasiewicz M. Landscape of biomolecular condensates in heat stress responses. FRONTIERS IN PLANT SCIENCE 2022; 13:1032045. [PMID: 36311142 PMCID: PMC9601738 DOI: 10.3389/fpls.2022.1032045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/21/2022] [Indexed: 06/06/2023]
Abstract
High temperature is one of the abiotic stresses that plants face and acts as a major constraint on crop production and food security. Plants have evolved several mechanisms to overcome challenging environments and respond to internal and external stimuli. One significant mechanism is the formation of biomolecular condensates driven by liquid-liquid phase separation. Biomolecular condensates have received much attention in the past decade, especially with regard to how plants perceive temperature fluctuations and their involvement in stress response and tolerance. In this review, we compile and discuss examples of plant biomolecular condensates regarding their composition, localization, and functions triggered by exposure to heat. Bioinformatic tools can be exploited to predict heat-induced biomolecular condensates. As the field of biomolecular condensates has emerged in the study of plants, many intriguing questions have arisen that have yet to be solved. Increased knowledge of biomolecular condensates will help in securing crop production and overcoming limitations caused by heat stress.
Collapse
|
7
|
Zhang H, Zhang X, Zhao J, Sun L, Wang H, Zhu Y, Xiao J, Wang X. Genome-Wide Identification of GDSL-Type Esterase/Lipase Gene Family in Dasypyrum villosum L. Reveals That DvGELP53 Is Related to BSMV Infection. Int J Mol Sci 2021; 22:ijms222212317. [PMID: 34830200 PMCID: PMC8624868 DOI: 10.3390/ijms222212317] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/21/2022] Open
Abstract
GDSL-type esterase/lipase proteins (GELPs) characterized by a conserved GDSL motif at their N-terminus belong to the lipid hydrolysis enzyme superfamily. In plants, GELPs play an important role in plant growth, development and stress response. The studies of the identification and characterization of the GELP gene family in Triticeae have not been reported. In this study, 193 DvGELPs were identified in Dasypyrum villosum and classified into 11 groups (clade A–K) by means of phylogenetic analysis. Most DvGELPs contain only one GDSL domain, only four DvGELPs contain other domains besides the GDSL domain. Gene structure analysis indicated 35.2% DvGELP genes have four introns and five exons. In the promoter regions of the identified DvGELPs, we detected 4502 putative cis-elements, which were associated with plant hormones, plant growth, environmental stress and light responsiveness. Expression profiling revealed 36, 44 and 17 DvGELPs were highly expressed in the spike, the root and the grain, respectively. Further investigation of a root-specific expressing GELP, DvGELP53, indicated it was induced by a variety of biotic and abiotic stresses. The knockdown of DvGELP53 inhibited long-distance movement of BSMV in the tissue of D. villosum. This research provides a genome-wide glimpse of the D. villosum GELP genes and hints at the participation of DvGELP53 in the interaction between virus and plants.
Collapse
Affiliation(s)
- Heng Zhang
- State Key Laboratory for Managing Biotic and Chemical Threats to The Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (H.Z.); (Y.Z.)
- State Key Lab of Crop Genetics and Germplasm Enhancement, Cytogenetics Institute, Nanjing Agricultural University/JCIC-MCP, Nanjing 210095, China; (X.Z.); (L.S.); (H.W.); (J.X.)
| | - Xu Zhang
- State Key Lab of Crop Genetics and Germplasm Enhancement, Cytogenetics Institute, Nanjing Agricultural University/JCIC-MCP, Nanjing 210095, China; (X.Z.); (L.S.); (H.W.); (J.X.)
| | - Jia Zhao
- College of Agriculture, South China Agriculture University, Guangzhou 510642, China;
| | - Li Sun
- State Key Lab of Crop Genetics and Germplasm Enhancement, Cytogenetics Institute, Nanjing Agricultural University/JCIC-MCP, Nanjing 210095, China; (X.Z.); (L.S.); (H.W.); (J.X.)
| | - Haiyan Wang
- State Key Lab of Crop Genetics and Germplasm Enhancement, Cytogenetics Institute, Nanjing Agricultural University/JCIC-MCP, Nanjing 210095, China; (X.Z.); (L.S.); (H.W.); (J.X.)
| | - Ying Zhu
- State Key Laboratory for Managing Biotic and Chemical Threats to The Quality and Safety of Agro-Products, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (H.Z.); (Y.Z.)
| | - Jin Xiao
- State Key Lab of Crop Genetics and Germplasm Enhancement, Cytogenetics Institute, Nanjing Agricultural University/JCIC-MCP, Nanjing 210095, China; (X.Z.); (L.S.); (H.W.); (J.X.)
| | - Xiue Wang
- State Key Lab of Crop Genetics and Germplasm Enhancement, Cytogenetics Institute, Nanjing Agricultural University/JCIC-MCP, Nanjing 210095, China; (X.Z.); (L.S.); (H.W.); (J.X.)
- Correspondence: ; Tel.: +86-25-84395308
| |
Collapse
|
8
|
Bagayoko I, Celli MG, Romay G, Poulicard N, Pinel-Galzi A, Julian C, Filloux D, Roumagnac P, Sérémé D, Bragard C, Hébrard E. Genetic Diversity of Rice stripe necrosis virus and New Insights into Evolution of the Genus Benyvirus. Viruses 2021; 13:v13050737. [PMID: 33922593 PMCID: PMC8145960 DOI: 10.3390/v13050737] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/12/2021] [Accepted: 04/21/2021] [Indexed: 01/02/2023] Open
Abstract
The rice stripe necrosis virus (RSNV) has been reported to infect rice in several countries in Africa and South America, but limited genomic data are currently publicly available. Here, eleven RSNV genomes were entirely sequenced, including the first corpus of RSNV genomes of African isolates. The genetic variability was differently distributed along the two genomic segments. The segment RNA1, within which clusters of polymorphisms were identified, showed a higher nucleotidic variability than did the beet necrotic yellow vein virus (BNYVV) RNA1 segment. The diversity patterns of both viruses were similar in the RNA2 segment, except for an in-frame insertion of 243 nucleotides located in the RSNV tgbp1 gene. Recombination events were detected into RNA1 and RNA2 segments, in particular in the two most divergent RSNV isolates from Colombia and Sierra Leone. In contrast to BNYVV, the RSNV molecular diversity had a geographical structure with two main RSNV lineages distributed in America and in Africa. Our data on the genetic diversity of RSNV revealed unexpected differences with BNYVV suggesting a complex evolutionary history of the genus Benyvirus.
Collapse
Affiliation(s)
- Issiaka Bagayoko
- Earth and Life Institute, Applied Microbiology-Phytopathology, Université Catholique de Louvain (UCLouvain), Croix du Sud 2 Bte L07.05.03, 1348 Louvain-la-Neuve, Belgium; (I.B.); (G.R.); (C.B.)
| | - Marcos Giovanni Celli
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina;
- Instituto de Patología Vegetal (IPAVE, CIAP, INTA), Camino 60 cuadras Km 5, Cordoba 5119, Argentina
| | - Gustavo Romay
- Earth and Life Institute, Applied Microbiology-Phytopathology, Université Catholique de Louvain (UCLouvain), Croix du Sud 2 Bte L07.05.03, 1348 Louvain-la-Neuve, Belgium; (I.B.); (G.R.); (C.B.)
| | - Nils Poulicard
- PHIM, Plant Health Institute, Université de Montpellier, IRD, INRAE, CIRAD, SupAgro, 911 Avenue Agropolis, 34394 Montpellier, France; (N.P.); (A.P.-G.); (C.J.); (D.F.); (P.R.)
| | - Agnès Pinel-Galzi
- PHIM, Plant Health Institute, Université de Montpellier, IRD, INRAE, CIRAD, SupAgro, 911 Avenue Agropolis, 34394 Montpellier, France; (N.P.); (A.P.-G.); (C.J.); (D.F.); (P.R.)
| | - Charlotte Julian
- PHIM, Plant Health Institute, Université de Montpellier, IRD, INRAE, CIRAD, SupAgro, 911 Avenue Agropolis, 34394 Montpellier, France; (N.P.); (A.P.-G.); (C.J.); (D.F.); (P.R.)
- CIRAD, UMR PHIM, Campus International de Montferrier-Baillarguet, 34398 Montpellier, France
| | - Denis Filloux
- PHIM, Plant Health Institute, Université de Montpellier, IRD, INRAE, CIRAD, SupAgro, 911 Avenue Agropolis, 34394 Montpellier, France; (N.P.); (A.P.-G.); (C.J.); (D.F.); (P.R.)
- CIRAD, UMR PHIM, Campus International de Montferrier-Baillarguet, 34398 Montpellier, France
| | - Philippe Roumagnac
- PHIM, Plant Health Institute, Université de Montpellier, IRD, INRAE, CIRAD, SupAgro, 911 Avenue Agropolis, 34394 Montpellier, France; (N.P.); (A.P.-G.); (C.J.); (D.F.); (P.R.)
- CIRAD, UMR PHIM, Campus International de Montferrier-Baillarguet, 34398 Montpellier, France
| | - Drissa Sérémé
- Laboratoire de Laboratoire de Virologie et de Biotechnologies Végétales, INERA—Institut de l’Environnement et de Recherches Agricoles, LMI Patho-Bios, Ouagadougou 01 BP 476, Burkina Faso;
| | - Claude Bragard
- Earth and Life Institute, Applied Microbiology-Phytopathology, Université Catholique de Louvain (UCLouvain), Croix du Sud 2 Bte L07.05.03, 1348 Louvain-la-Neuve, Belgium; (I.B.); (G.R.); (C.B.)
| | - Eugénie Hébrard
- PHIM, Plant Health Institute, Université de Montpellier, IRD, INRAE, CIRAD, SupAgro, 911 Avenue Agropolis, 34394 Montpellier, France; (N.P.); (A.P.-G.); (C.J.); (D.F.); (P.R.)
- Correspondence:
| |
Collapse
|
9
|
Leastro MO, Freitas-Astúa J, Kitajima EW, Pallás V, Sánchez-Navarro JA. Unravelling the involvement of cilevirus p32 protein in the viral transport. Sci Rep 2021; 11:2943. [PMID: 33536554 PMCID: PMC7859179 DOI: 10.1038/s41598-021-82453-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 01/13/2021] [Indexed: 12/04/2022] Open
Abstract
Citrus leprosis (CL) is a severe disease that affects citrus orchards mainly in Latin America. It is caused by Brevipalpus-transmitted viruses from genera Cilevirus and Dichorhavirus. Currently, no reports have explored the movement machinery for the cilevirus. Here, we have performed a detailed functional study of the p32 movement protein (MP) of two cileviruses. Citrus leprosis-associated viruses are not able to move systemically in neither their natural nor experimental host plants. However, here we show that cilevirus MPs are able to allow the cell-to-cell and long-distance transport of movement-defective alfalfa mosaic virus (AMV). Several features related with the viral transport were explored, including: (i) the ability of cilevirus MPs to facilitate virus movement on a nucleocapsid assembly independent-manner; (ii) the generation of tubular structures from transient expression in protoplast; (iii) the capability of the N- and C- terminus of MP to interact with the cognate capsid protein (p29) and; (iv) the role of the C-terminus of p32 in the cell-to-cell and long-distance transport, tubule formation and the MP-plasmodesmata co-localization. The MP was able to direct the p29 to the plasmodesmata, whereby the C-terminus of MP is independently responsible to recruit the p29 to the cell periphery. Furthermore, we report that MP possess the capacity to enter the nucleolus and to bind to a major nucleolar protein, the fibrillarin. Based on our findings, we provide a model for the role of the p32 in the intra- and intercellular viral spread.
Collapse
Affiliation(s)
- Mikhail Oliveira Leastro
- Unidade Laboratorial de Referência em Biologia Molecular Aplicada, Instituto Biológico, São Paulo, SP, Brazil. .,Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain.
| | - Juliana Freitas-Astúa
- Unidade Laboratorial de Referência em Biologia Molecular Aplicada, Instituto Biológico, São Paulo, SP, Brazil.,Embrapa Mandioca e Fruticultura, Cruz das Almas, BA, Brazil
| | - Elliot Watanabe Kitajima
- Departamento de Fitopatologia e Nematologia, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Vicente Pallás
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain
| | - Jesús A Sánchez-Navarro
- Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas (CSIC), Valencia, Spain.
| |
Collapse
|
10
|
Taliansky M, Samarskaya V, Zavriev SK, Fesenko I, Kalinina NO, Love AJ. RNA-Based Technologies for Engineering Plant Virus Resistance. PLANTS 2021; 10:plants10010082. [PMID: 33401751 PMCID: PMC7824052 DOI: 10.3390/plants10010082] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/25/2020] [Accepted: 12/27/2020] [Indexed: 02/07/2023]
Abstract
In recent years, non-coding RNAs (ncRNAs) have gained unprecedented attention as new and crucial players in the regulation of numerous cellular processes and disease responses. In this review, we describe how diverse ncRNAs, including both small RNAs and long ncRNAs, may be used to engineer resistance against plant viruses. We discuss how double-stranded RNAs and small RNAs, such as artificial microRNAs and trans-acting small interfering RNAs, either produced in transgenic plants or delivered exogenously to non-transgenic plants, may constitute powerful RNA interference (RNAi)-based technology that can be exploited to control plant viruses. Additionally, we describe how RNA guided CRISPR-CAS gene-editing systems have been deployed to inhibit plant virus infections, and we provide a comparative analysis of RNAi approaches and CRISPR-Cas technology. The two main strategies for engineering virus resistance are also discussed, including direct targeting of viral DNA or RNA, or inactivation of plant host susceptibility genes. We also elaborate on the challenges that need to be overcome before such technologies can be broadly exploited for crop protection against viruses.
Collapse
Affiliation(s)
- Michael Taliansky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (V.S.); (S.K.Z.); (I.F.); (N.O.K.)
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
- Correspondence: (M.T.); (A.J.L.)
| | - Viktoria Samarskaya
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (V.S.); (S.K.Z.); (I.F.); (N.O.K.)
| | - Sergey K. Zavriev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (V.S.); (S.K.Z.); (I.F.); (N.O.K.)
| | - Igor Fesenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (V.S.); (S.K.Z.); (I.F.); (N.O.K.)
| | - Natalia O. Kalinina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (V.S.); (S.K.Z.); (I.F.); (N.O.K.)
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, 119991 Moscow, Russia
| | - Andrew J. Love
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
- Correspondence: (M.T.); (A.J.L.)
| |
Collapse
|
11
|
Rajamäki ML, Sikorskaite-Gudziuniene S, Sarmah N, Varjosalo M, Valkonen JPT. Nuclear proteome of virus-infected and healthy potato leaves. BMC PLANT BIOLOGY 2020; 20:355. [PMID: 32727361 PMCID: PMC7392702 DOI: 10.1186/s12870-020-02561-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 07/20/2020] [Indexed: 05/30/2023]
Abstract
BACKGROUND Infection of plants by viruses interferes with expression and subcellular localization of plant proteins. Potyviruses comprise the largest and most economically damaging group of plant-infecting RNA viruses. In virus-infected cells, at least two potyviral proteins localize to nucleus but reasons remain partly unknown. RESULTS In this study, we examined changes in the nuclear proteome of leaf cells from a diploid potato line (Solanum tuberosum L.) after infection with potato virus A (PVA; genus Potyvirus; Potyviridae) and compared the data with that acquired for healthy leaves. Gel-free liquid chromatography-coupled to tandem mass spectrometry was used to identify 807 nuclear proteins in the potato line v2-108; of these proteins, 370 were detected in at least two samples of healthy leaves. A total of 313 proteins were common in at least two samples of healthy and PVA-infected leaves; of these proteins, 8 showed differential accumulation. Sixteen proteins were detected exclusively in the samples from PVA-infected leaves, whereas other 16 proteins were unique to healthy leaves. The protein Dnajc14 was only detected in healthy leaves, whereas different ribosomal proteins, ribosome-biogenesis proteins, and RNA splicing-related proteins were over-represented in the nuclei of PVA-infected leaves. Two virus-encoded proteins were identified in the samples of PVA-infected leaves. CONCLUSIONS Our results show that PVA infection alters especially ribosomes and splicing-related proteins in the nucleus of potato leaves. The data increase our understanding of potyvirus infection and the role of nucleus in infection. To our knowledge, this is the first study of the nuclear proteome of potato leaves and one of the few studies of changes occurring in nuclear proteomes in response to plant virus infection.
Collapse
Affiliation(s)
- Minna-Liisa Rajamäki
- Department of Agricultural Sciences, University of Helsinki, PO Box 27, FI-00014, Helsinki, Finland.
| | - Sidona Sikorskaite-Gudziuniene
- Department of Agricultural Sciences, University of Helsinki, PO Box 27, FI-00014, Helsinki, Finland
- Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry, Kaunas Street 30, Babtai, LT-54333, Kaunas District, Lithuania
| | - Nandita Sarmah
- Department of Agricultural Sciences, University of Helsinki, PO Box 27, FI-00014, Helsinki, Finland
| | - Markku Varjosalo
- Institute of Biotechnology, University of Helsinki, PO Box 56, FI-00014, Helsinki, Finland
| | - Jari P T Valkonen
- Department of Agricultural Sciences, University of Helsinki, PO Box 27, FI-00014, Helsinki, Finland
| |
Collapse
|
12
|
Chimeric Virus Made from crTMV RNA and the Coat Protein of Potato Leafroll Virus is Targeted to the Nucleolus and Can Infect Nicotiana benthamiana Mechanically. High Throughput 2020; 9:ht9020011. [PMID: 32357496 PMCID: PMC7348827 DOI: 10.3390/ht9020011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/02/2020] [Accepted: 04/22/2020] [Indexed: 11/30/2022] Open
Abstract
A genetically engineered chimeric virus crTMV-CP-PLRV composed of the crucifer-infecting tobacco mosaic virus (crTMV) RNA and the potato leafroll virus (PLRV) coat protein (CP) was obtained by agroinfiltration of Nicotiana benthamiana with the binary vector pCambia-crTMV-CPPLRV. The significant levels of the chimeric virus enabled direct visualization of crTMV-CP-PLRV in the cell and to investigate the mechanism of the pathogenesis. Localization of the crTMV-CP-PLRV in plant cells was examined by immunoblot techniques, as well as light, and transmission electron microscopy. The chimera can transfer between vascular and nonvascular tissues. The chimeric virus inoculum is capable to infect N. benthamiana mechanically. The distinguishing feature of the chimeric virus, the RNA virus with the positive genome, was found to localize in the nucleolus. We also investigated the role of the N-terminal sequence of the PLRV P3 coat protein in the cellular localization of the virus. We believe that the gene of the PLRV CP can be substituted with genes from other challenging-to-study plant pathogens to produce other useful recombinant viruses.
Collapse
|
13
|
Xu M, Mazur MJ, Tao X, Kormelink R. Cellular RNA Hubs: Friends and Foes of Plant Viruses. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:40-54. [PMID: 31415225 DOI: 10.1094/mpmi-06-19-0161-fi] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
RNA granules are dynamic cellular foci that are widely spread in eukaryotic cells and play essential roles in cell growth and development, and immune and stress responses. Different types of granules can be distinguished, each with a specific function and playing a role in, for example, RNA transcription, modification, processing, decay, translation, and arrest. By means of communication and exchange of (shared) components, they form a large regulatory network in cells. Viruses have been reported to interact with one or more of these either cytoplasmic or nuclear granules, and act either proviral, to enable and support viral infection and facilitate viral movement, or antiviral, protecting or clearing hosts from viral infection. This review describes an overview and recent progress on cytoplasmic and nuclear RNA granules and their interplay with virus infection, first in animal systems and as a prelude to the status and current developments on plant viruses, which have been less well studied on this thus far.
Collapse
Affiliation(s)
- Min Xu
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Virology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| | - Magdalena J Mazur
- Laboratory of Virology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| | - Xiaorong Tao
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
| | - Richard Kormelink
- Laboratory of Virology, Department of Plant Sciences, Wageningen University & Research, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| |
Collapse
|
14
|
Cottilli P, Belda-Palazón B, Adkar-Purushothama CR, Perreault JP, Schleiff E, Rodrigo I, Ferrando A, Lisón P. Citrus exocortis viroid causes ribosomal stress in tomato plants. Nucleic Acids Res 2019; 47:8649-8661. [PMID: 31392997 PMCID: PMC6895259 DOI: 10.1093/nar/gkz679] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/23/2019] [Accepted: 07/30/2019] [Indexed: 12/26/2022] Open
Abstract
Viroids are naked RNAs that do not code for any known protein and yet are able to infect plants causing severe diseases. Because of their RNA nature, many studies have focused on the involvement of viroids in RNA-mediated gene silencing as being their pathogenesis mechanism. Here, the alterations caused by the Citrus exocortis viroid (CEVd) on the tomato translation machinery were studied as a new aspect of viroid pathogenesis. The presence of viroids in the ribosomal fractions of infected tomato plants was detected. More precisely, CEVd and its derived viroid small RNAs were found to co-sediment with tomato ribosomes in vivo, and to provoke changes in the global polysome profiles, particularly in the 40S ribosomal subunit accumulation. Additionally, the viroid caused alterations in ribosome biogenesis in the infected tomato plants, affecting the 18S rRNA maturation process. A higher expression level of the ribosomal stress mediator NAC082 was also detected in the CEVd-infected tomato leaves. Both the alterations in the rRNA processing and the induction of NAC082 correlate with the degree of viroid symptomatology. Taken together, these results suggest that CEVd is responsible for defective ribosome biogenesis in tomato, thereby interfering with the translation machinery and, therefore, causing ribosomal stress.
Collapse
Affiliation(s)
- Patrick Cottilli
- Instituto de Biología Molecular y Celular de Plantas. Universitat Politècnica de València (UPV) - Consejo Superior de Investigaciones Científicas (CSIC). Ciudad Politécnica de la Innovación (CPI), Valencia 46022, Spain
| | - Borja Belda-Palazón
- Instituto de Biología Molecular y Celular de Plantas. Universitat Politècnica de València (UPV) - Consejo Superior de Investigaciones Científicas (CSIC). Ciudad Politécnica de la Innovación (CPI), Valencia 46022, Spain
| | - Charith Raj Adkar-Purushothama
- RNA Group, Département de Biochimie, Faculté de Médecine des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, Sherbrooke, Québec J1E 4K8, Canada
| | - Jean-Pierre Perreault
- RNA Group, Département de Biochimie, Faculté de Médecine des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, Sherbrooke, Québec J1E 4K8, Canada
| | - Enrico Schleiff
- Department of Biosciences, Molecular Cell Biology of Plants & Buchmann Institute for Molecular Life Science, Goethe University; Frankfurt Institute for Advanced Studies; Frankfurt/Main 60438, Germany
| | - Ismael Rodrigo
- Instituto de Biología Molecular y Celular de Plantas. Universitat Politècnica de València (UPV) - Consejo Superior de Investigaciones Científicas (CSIC). Ciudad Politécnica de la Innovación (CPI), Valencia 46022, Spain
| | - Alejandro Ferrando
- Instituto de Biología Molecular y Celular de Plantas. Universitat Politècnica de València (UPV) - Consejo Superior de Investigaciones Científicas (CSIC). Ciudad Politécnica de la Innovación (CPI), Valencia 46022, Spain
| | - Purificación Lisón
- Instituto de Biología Molecular y Celular de Plantas. Universitat Politècnica de València (UPV) - Consejo Superior de Investigaciones Científicas (CSIC). Ciudad Politécnica de la Innovación (CPI), Valencia 46022, Spain
| |
Collapse
|
15
|
Shaw J, Yu C, Makhotenko AV, Makarova SS, Love AJ, Kalinina NO, MacFarlane S, Chen J, Taliansky ME. Interaction of a plant virus protein with the signature Cajal body protein coilin facilitates salicylic acid-mediated plant defence responses. THE NEW PHYTOLOGIST 2019; 224:439-453. [PMID: 31215645 DOI: 10.1111/nph.15994] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 06/06/2019] [Indexed: 05/22/2023]
Abstract
In addition to well-known roles in RNA metabolism, the nucleolus and Cajal bodies (CBs), both located within the nucleus, are involved in plant responses to biotic and abiotic stress. Previously we showed that plants in which expression of the CB protein coilin is downregulated are more susceptible to certain viruses including tobacco rattle virus (TRV), suggesting a role of coilin in antiviral defence. Experiments with coilin-deficient plants and the deletion mutant of the TRV 16K protein showed that both 16K and coilin are required for restriction of systemic TRV infection. The potential mechanisms of coilin-mediated antiviral defence were elucidated via experiments involving co-immunoprecipitation, use of NahG transgenic plants deficient in salicylic acid (SA) accumulation, measurement of endogenous SA concentrations and assessment of SA-responsive gene expression. Here we show that TRV 16K interacts with and relocalizes coilin to the nucleolus. In wild-type plants these events are accompanied by activation of SA-responsive gene expression and restriction of TRV systemic infection. By contrast, viral systemic spread was enhanced in NahG plants, implicating SA in these processes. Our findings suggest that coilin is involved in plant defence, responding to TRV infection by recognition of the TRV-encoded 16K protein and activating SA-dependent defence pathways.
Collapse
Affiliation(s)
- Jane Shaw
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Chulang Yu
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
- State Key Laboratory for Quality and Safety of Agro-products, Institute of Plant Virology, Ningbo University, Ningbo, 117997, China
| | - Antonida V Makhotenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the RAS, Moscow, 117997, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, Moscow, 119991, Russia
| | - Svetlana S Makarova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the RAS, Moscow, 117997, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, Moscow, 119991, Russia
| | - Andrew J Love
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Natalia O Kalinina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the RAS, Moscow, 117997, Russia
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, Moscow, 119991, Russia
| | - Stuart MacFarlane
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Jianping Chen
- State Key Laboratory for Quality and Safety of Agro-products, Institute of Plant Virology, Ningbo University, Ningbo, 117997, China
| | - Michael E Taliansky
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the RAS, Moscow, 117997, Russia
| |
Collapse
|
16
|
Navarro JA, Sanchez-Navarro JA, Pallas V. Key checkpoints in the movement of plant viruses through the host. Adv Virus Res 2019; 104:1-64. [PMID: 31439146 DOI: 10.1016/bs.aivir.2019.05.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Plant viruses cannot exploit any of the membrane fusion-based routes of entry described for animal viruses. In addition, one of the distinctive structures of plant cells, the cell wall, acts as the first barrier against the invasion of pathogens. To overcome the rigidity of the cell wall, plant viruses normally take advantage of the way of life of different biological vectors. Alternatively, the physical damage caused by environmental stresses can facilitate virus entry. Once inside the cell and taking advantage of the characteristic symplastic continuity of plant cells, viruses need to remodel and/or modify the restricted pore size of the plasmodesmata (channels that connect plant cells). In a successful interaction for the virus, it can reach the vascular tissue to systematically invade the plant. The connections between the different cell types in this path are not designed to allow the passage of molecules with the complexity of viruses. During this process, viruses face different cell barriers that must be overcome to reach the distal parts of the plant. In this review, we highlight the current knowledge about how plant RNA viruses enter plant cells, move between them to reach vascular cells and overcome the different physical and cellular barriers that the phloem imposes. Finally, we update the current research on cellular organelles as key regulator checkpoints in the long-distance movement of plant viruses.
Collapse
Affiliation(s)
- Jose A Navarro
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Jesus A Sanchez-Navarro
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Vicente Pallas
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Valencia, Spain.
| |
Collapse
|
17
|
Pérez-Cañamás M, Hernández C. New Insights into the Nucleolar Localization of a Plant RNA Virus-Encoded Protein That Acts in Both RNA Packaging and RNA Silencing Suppression: Involvement of Importins Alpha and Relevance for Viral Infection. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:1134-1144. [PMID: 29781763 DOI: 10.1094/mpmi-02-18-0050-r] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Despite the fact that replication of plus-strand RNA viruses takes place in the cytoplasm of host cells, different proteins encoded by these infectious agents have been shown to localize in the nucleus, with high accumulation at the nucleolus. In most cases, the molecular determinants or biological significance of such subcellular localization remains elusive. Recently, we reported that protein p37 encoded by Pelargonium line pattern virus (family Tombusviridae) acts in both RNA packaging and RNA silencing suppression. Consistently with these functions, p37 was detected in the cytoplasm of plant cells, although it was also present in the nucleus and, particularly, in the nucleolus. Here, we searched for further insights into factors influencing p37 nucleolar localization and into its potential relevance for viral infection. Besides mapping the protein region containing the nucleolar localization signal, we have found that p37 interacts with distinct members of the importin alpha family-main cellular transporters for nucleo-cytoplasmic traffic of proteins-and that these interactions are crucial for nucleolar targeting of p37. Impairment of p37 nucleolar localization through downregulation of importin alpha expression resulted in a reduction of viral accumulation, suggesting that sorting of the protein to the major subnuclear compartment is advantageous for the infection process.
Collapse
Affiliation(s)
- Miryam Pérez-Cañamás
- Instituto de Biología Molecular y Celular de Plantas (Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia). Ciudad Politécnica de la Innovación, Ed. 8E. Camino de Vera s/n, 46022 Valencia, Spain
| | - Carmen Hernández
- Instituto de Biología Molecular y Celular de Plantas (Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia). Ciudad Politécnica de la Innovación, Ed. 8E. Camino de Vera s/n, 46022 Valencia, Spain
| |
Collapse
|
18
|
Li Z, Zhang Y, Jiang Z, Jin X, Zhang K, Wang X, Han C, Yu J, Li D. Hijacking of the nucleolar protein fibrillarin by TGB1 is required for cell-to-cell movement of Barley stripe mosaic virus. MOLECULAR PLANT PATHOLOGY 2018; 19:1222-1237. [PMID: 28872759 PMCID: PMC6638131 DOI: 10.1111/mpp.12612] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/31/2017] [Accepted: 09/04/2017] [Indexed: 05/18/2023]
Abstract
Barley stripe mosaic virus (BSMV) Triple Gene Block1 (TGB1) is a multifunctional movement protein with RNA-binding, ATPase and helicase activities which mainly localizes to the plasmodesmata (PD) in infected cells. Here, we show that TGB1 localizes to the nucleus and the nucleolus, as well as the cytoplasm, and that TGB1 nuclear-cytoplasmic trafficking is required for BSMV cell-to-cell movement. Prediction analyses and laser scanning confocal microscopy (LSCM) experiments verified that TGB1 possesses a nucleolar localization signal (NoLS) (amino acids 95-104) and a nuclear localization signal (NLS) (amino acids 227-238). NoLS mutations reduced BSMV cell-to-cell movement significantly, whereas NLS mutations almost completely abolished movement. Furthermore, neither the NoLS nor NLS mutant viruses could infect Nicotiana benthamiana systemically, although the NoLS mutant virus was able to establish systemic infections of barley. Protein interaction experiments demonstrated that TGB1 interacts directly with the glycine-arginine-rich (GAR) domain of the nucleolar protein fibrillarin (Fib2). Moreover, in BSMV-infected cells, Fib2 accumulation increased by about 60%-70% and co-localized with TGB1 in the plasmodesmata. In addition, BSMV cell-to-cell movement in fib2 knockdown transgenic plants was reduced to less than one-third of that of non-transgenic plants. Fib2 also co-localized with both TGB1 and BSMV RNA, which are the main components of the ribonucleoprotein (RNP) movement complex. Collectively, these results show that TGB1-Fib2 interactions play a direct role in cell-to-cell movement, and we propose that Fib2 is hijacked by BSMV TGB1 to form a BSMV RNP which functions in cell-to-cell movement.
Collapse
Affiliation(s)
- Zhenggang Li
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Yongliang Zhang
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Zhihao Jiang
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Xuejiao Jin
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Kun Zhang
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Xianbing Wang
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Chenggui Han
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Jialin Yu
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| | - Dawei Li
- State Key Laboratory of Agro‐Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological SciencesChina Agricultural UniversityBeijing 100193China
| |
Collapse
|
19
|
Cowan GH, Roberts AG, Jones S, Kumar P, Kalyandurg PB, Gil JF, Savenkov EI, Hemsley PA, Torrance L. Potato Mop-Top Virus Co-Opts the Stress Sensor HIPP26 for Long-Distance Movement. PLANT PHYSIOLOGY 2018; 176:2052-2070. [PMID: 29374107 PMCID: PMC5841704 DOI: 10.1104/pp.17.01698] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/12/2018] [Indexed: 05/03/2023]
Abstract
Virus movement proteins facilitate virus entry into the vascular system to initiate systemic infection. The potato mop-top virus (PMTV) movement protein, TGB1, is involved in long-distance movement of both viral ribonucleoprotein complexes and virions. Here, our analysis of TGB1 interactions with host Nicotiana benthamiana proteins revealed an interaction with a member of the heavy metal-associated isoprenylated plant protein family, HIPP26, which acts as a plasma membrane-to-nucleus signal during abiotic stress. We found that knockdown of NbHIPP26 expression inhibited virus long-distance movement but did not affect cell-to-cell movement. Drought and PMTV infection up-regulated NbHIPP26 gene expression, and PMTV infection protected plants from drought. In addition, NbHIPP26 promoter-reporter fusions revealed vascular tissue-specific expression. Mutational and biochemical analyses indicated that NbHIPP26 subcellular localization at the plasma membrane and plasmodesmata was mediated by lipidation (S-acylation and prenylation), as nonlipidated NbHIPP26 was predominantly in the nucleus. Notably, coexpression of NbHIPP26 with TGB1 resulted in a similar nuclear accumulation of NbHIPP26. TGB1 interacted with the carboxyl-terminal CVVM (prenyl) domain of NbHIPP26, and bimolecular fluorescence complementation revealed that the TGB1-HIPP26 complex localized to microtubules and accumulated in the nucleolus, with little signal at the plasma membrane or plasmodesmata. These data support a mechanism where interaction with TGB1 negates or reverses NbHIPP26 lipidation, thus releasing membrane-associated NbHIPP26 and redirecting it via microtubules to the nucleus, thereby activating the drought stress response and facilitating virus long-distance movement.
Collapse
Affiliation(s)
- Graham H Cowan
- James Hutton Institute, Invergowrie DD2 5DA, United Kingdom
| | | | - Susan Jones
- James Hutton Institute, Invergowrie DD2 5DA, United Kingdom
| | - Pankaj Kumar
- School of Biology, University of St. Andrews, St. Andrews, Fife KY16 9ST, United Kingdom
| | - Pruthvi B Kalyandurg
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
| | - Jose F Gil
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
| | - Eugene I Savenkov
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
| | - Piers A Hemsley
- James Hutton Institute, Invergowrie DD2 5DA, United Kingdom
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Invergowrie DD2 5DA, United Kingdom
| | - Lesley Torrance
- James Hutton Institute, Invergowrie DD2 5DA, United Kingdom
- School of Biology, University of St. Andrews, St. Andrews, Fife KY16 9ST, United Kingdom
| |
Collapse
|
20
|
Kalinina NO, Makarova S, Makhotenko A, Love AJ, Taliansky M. The Multiple Functions of the Nucleolus in Plant Development, Disease and Stress Responses. FRONTIERS IN PLANT SCIENCE 2018; 9:132. [PMID: 29479362 PMCID: PMC5811523 DOI: 10.3389/fpls.2018.00132] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/23/2018] [Indexed: 05/18/2023]
Abstract
The nucleolus is the most conspicuous domain in the eukaryotic cell nucleus, whose main function is ribosomal RNA (rRNA) synthesis and ribosome biogenesis. However, there is growing evidence that the nucleolus is also implicated in many other aspects of cell biology, such as regulation of cell cycle, growth and development, senescence, telomerase activity, gene silencing, responses to biotic and abiotic stresses. In the first part of the review, we briefly assess the traditional roles of the plant nucleolus in rRNA synthesis and ribosome biogenesis as well as possible functions in other RNA regulatory pathways such as splicing, nonsense-mediated mRNA decay and RNA silencing. In the second part of the review we summarize recent progress and discuss already known and new hypothetical roles of the nucleolus in plant growth and development. In addition, this part will highlight studies showing new nucleolar functions involved in responses to pathogen attack and abiotic stress. Cross-talk between the nucleolus and Cajal bodies is also discussed in the context of their association with poly(ADP ribose)polymerase (PARP), which is known to play a crucial role in various physiological processes including growth, development and responses to biotic and abiotic stresses.
Collapse
Affiliation(s)
- Natalia O. Kalinina
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia
- Natalia O. Kalinina
| | - Svetlana Makarova
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia
| | - Antonida Makhotenko
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia
| | | | - Michael Taliansky
- Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow, Russia
- The James Hutton Institute, Dundee, United Kingdom
- *Correspondence: Michael Taliansky
| |
Collapse
|
21
|
Love AJ, Yu C, Petukhova NV, Kalinina NO, Chen J, Taliansky ME. Cajal bodies and their role in plant stress and disease responses. RNA Biol 2017; 14:779-790. [PMID: 27726481 PMCID: PMC5519230 DOI: 10.1080/15476286.2016.1243650] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/19/2016] [Accepted: 09/27/2016] [Indexed: 12/11/2022] Open
Abstract
Cajal bodies (CBs) are distinct sub-nuclear structures that are present in eukaryotic living cells and are often associated with the nucleolus. CBs play important roles in RNA metabolism and formation of RNPs involved in transcription, splicing, ribosome biogenesis, and telomere maintenance. Besides these primary roles, CBs appear to be involved in additional functions that may not be directly related to RNA metabolism and RNP biogenesis. In this review, we assess possible roles of plant CBs in RNA regulatory pathways such as nonsense-mediated mRNA decay and RNA silencing. We also summarize recent progress and discuss new non-canonical functions of plant CBs in responses to stress and disease. It is hypothesized that CBs can regulate these responses via their interaction with poly(ADP ribose)polymerase (PARP), which is known to play an important role in various physiological processes including responses to biotic and abiotic stresses. It is suggested that CBs and their components modify PARP activities and functions.
Collapse
Affiliation(s)
- Andrew J. Love
- Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, UK
| | - Chulang Yu
- State Key Laboratory Breeding Base for Sustainable Pest and Disease Control, Key Laboratory of Biotechnology in Plant Protection of MOA and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | | | - Natalia O. Kalinina
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninskie Gory, Moscow, Russia
| | - Jianping Chen
- State Key Laboratory Breeding Base for Sustainable Pest and Disease Control, Key Laboratory of Biotechnology in Plant Protection of MOA and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Michael E. Taliansky
- Cell and Molecular Sciences, James Hutton Institute, Invergowrie, Dundee, UK
- State Key Laboratory Breeding Base for Sustainable Pest and Disease Control, Key Laboratory of Biotechnology in Plant Protection of MOA and Zhejiang Province, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| |
Collapse
|
22
|
Chang CH, Hsu FC, Lee SC, Lo YS, Wang JD, Shaw J, Taliansky M, Chang BY, Hsu YH, Lin NS. The Nucleolar Fibrillarin Protein Is Required for Helper Virus-Independent Long-Distance Trafficking of a Subviral Satellite RNA in Plants. THE PLANT CELL 2016; 28:2586-2602. [PMID: 27702772 PMCID: PMC5134973 DOI: 10.1105/tpc.16.00071] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 08/30/2016] [Accepted: 09/30/2016] [Indexed: 05/03/2023]
Abstract
RNA trafficking plays pivotal roles in regulating plant development, gene silencing, and adaptation to environmental stress. Satellite RNAs (satRNAs), parasites of viruses, depend on their helper viruses (HVs) for replication, encapsidation, and efficient spread. However, it remains largely unknown how satRNAs interact with viruses and the cellular machinery to undergo trafficking. Here, we show that the P20 protein of Bamboo mosaic potexvirus satRNA (satBaMV) can functionally complement in trans the systemic trafficking of P20-defective satBaMV in infected Nicotiana benthamiana The transgene-derived satBaMV, uncoupled from HV replication, was able to move autonomously across a graft union identified by RT-qPCR, RNA gel blot, and in situ RT-PCR analyses. Coimmunoprecipitation experiments revealed that the major nucleolar protein fibrillarin is coprecipitated in the P20 protein complex. Notably, silencing fibrillarin suppressed satBaMV-, but not HV-, phloem-based movement following grafting or coinoculation with HV Confocal microscopy revealed that the P20 protein colocalized with fibrillarin in the nucleoli and formed punctate structures associated with plasmodesmata. The mobile satBaMV RNA appears to exist as ribonucleoprotein (RNP) complex composed of P20 and fibrillarin, whereas BaMV movement proteins, capsid protein, and BaMV RNA are recruited with HV coinfection. Taken together, our findings provide insight into movement of satBaMV via the fibrillarin-satBaMV-P20 RNP complex in phloem-mediated systemic trafficking.
Collapse
Affiliation(s)
- Chih-Hao Chang
- Institute of Plant Biology, National Taiwan University, Taipei 11106, Taiwan
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Fu-Chen Hsu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Shu-Chuan Lee
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Yih-Shan Lo
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Jiun-Da Wang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Jane Shaw
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, United Kingdom
| | - Michael Taliansky
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, United Kingdom
| | - Ban-Yang Chang
- Department of Biochemistry, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yau-Heiu Hsu
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan
| | - Na-Sheng Lin
- Institute of Plant Biology, National Taiwan University, Taipei 11106, Taiwan
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| |
Collapse
|
23
|
Zheng L, Yao J, Gao F, Chen L, Zhang C, Lian L, Xie L, Wu Z, Xie L. The Subcellular Localization and Functional Analysis of Fibrillarin2, a Nucleolar Protein in Nicotiana benthamiana. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2831287. [PMID: 26885505 PMCID: PMC4738988 DOI: 10.1155/2016/2831287] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/01/2015] [Indexed: 01/28/2023]
Abstract
Nucleolar proteins play important roles in plant cytology, growth, and development. Fibrillarin2 is a nucleolar protein of Nicotiana benthamiana (N. benthamiana). Its cDNA was amplified by RT-PCR and inserted into expression vector pEarley101 labeled with yellow fluorescent protein (YFP). The fusion protein was localized in the nucleolus and Cajal body of leaf epidermal cells of N. benthamiana. The N. benthamiana fibrillarin2 (NbFib2) protein has three functional domains (i.e., glycine and arginine rich domain, RNA-binding domain, and α-helical domain) and a nuclear localization signal (NLS) in C-terminal. The protein 3D structure analysis predicted that NbFib2 is an α/β protein. In addition, the virus induced gene silencing (VIGS) approach was used to determine the function of NbFib2. Our results showed that symptoms including growth retardation, organ deformation, chlorosis, and necrosis appeared in NbFib2-silenced N. benthamiana.
Collapse
Affiliation(s)
- Luping Zheng
- Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jinai Yao
- Institute of Plant Protection, Fujian Provincial Academy of Agricultural Sciences, Fuzhou 350002, China
| | - Fangluan Gao
- Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Lin Chen
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Chao Zhang
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Lingli Lian
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Liyan Xie
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zujian Wu
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Lianhui Xie
- Key Laboratory of Plant Virology of Fujian Province, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| |
Collapse
|
24
|
Zheng L, Du Z, Lin C, Mao Q, Wu K, Wu J, Wei T, Wu Z, Xie L. Rice stripe tenuivirus p2 may recruit or manipulate nucleolar functions through an interaction with fibrillarin to promote virus systemic movement. MOLECULAR PLANT PATHOLOGY 2015; 16:921-30. [PMID: 25431002 PMCID: PMC6638460 DOI: 10.1111/mpp.12220] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Rice stripe virus (RSV) is the type species of the genus Tenuivirus and represents a major viral pathogen affecting rice production in East Asia. In this study, RSV p2 was fused to yellow fluorescent protein (p2-YFP) and expressed in epidermal cells of Nicotiana benthamiana. p2-YFP fluorescence was found to move to the nucleolus initially, but to leave the nucleolus for the cytoplasm forming numerous distinct bright spots there at later time points. A bimolecular fluorescence complementation (BiFC) assay showed that p2 interacted with fibrillarin and that the interaction occurred in the nucleus. Both the nucleolar localization and cytoplasmic distribution of p2-YFP fluorescence were affected in fibrillarin-silenced N. benthamiana. Fibrillarin depletion abolished the systemic movement of RSV, but not that of Tobacco mosaic virus (TMV) and Potato virus X (PVX). A Tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS) method was used to diminish RSV NS2 (encoding p2) or NS3 (encoding p3) during RSV infection. Silencing of NS3 alleviated symptom severity and reduced RSV accumulation, but had no obvious effects on virus movement and the timing of symptom development. However, silencing of NS2 abolished the systemic movement of RSV. The possibility that RSV p2 may recruit or manipulate nucleolar functions to promote virus systemic infection is discussed.
Collapse
Affiliation(s)
- Luping Zheng
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zhenguo Du
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Plant Protection Research Institute, GAAS, Guangzhou, 510640, China
| | - Chen Lin
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- Bayuquan Entry-Exit Inspection and Quarantine Bureau, Yingkou, 115007, China
| | - Qianzhuo Mao
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Kangcheng Wu
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Jianguo Wu
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Taiyun Wei
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zujian Wu
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Lianhui Xie
- Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| |
Collapse
|
25
|
Makarov VV, Makarova SS, Makhotenko AV, Obraztsova EA, Kalinina NO. In vitro properties of hordeivirus TGB1 protein forming ribonucleoprotein complexes. J Gen Virol 2015; 96:3422-3431. [PMID: 26276346 DOI: 10.1099/jgv.0.000252] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hordeivirus movement protein encoded by the first gene of the triple gene block (TGB1 protein, TGBp1) interacts in vivo with viral genomic and subgenomic RNAs to form ribonucleoprotein (RNP) particles that are considered to be a form of viral genome (non-virion transport form) capable of cell-to-cell and long-distance transport in infected plants. The structures of these RNPs have not been elucidated. The poa semilatent virus (PSLV) TGBp1 contains a structured C-terminal NTPase/helicase domain and an N-terminal extension region consisting of two domains - a completely intrinsically disordered extreme N-terminal domain and an internal domain (ID) with structure resembling a partially disordered molten globule. Here, we characterized the structures assembled in vitro by the full-length PSLV TGBp1 alone or in the presence of viral RNA. The PSLV TGBp1 was capable of multimerization and self-assembly into extended high-molecular-mass complexes. These complexes disassembled to apparent monomers upon incubation with ATP. Upon incubation with viral RNA, the PSLV TGBp1 in vitro formed RNP structures that appeared as filamentous particles resembling virions of helical filamentous plant viruses in morphology and dimensions. By comparing the biophysical characteristics of PSLV TGBp1 and its domains in the presence and absence of RNA, we show that the ID plays the main structural role in the self-interactions and RNA interactions of TGBp1 leading to the assembly of virus-like RNP particles.
Collapse
Affiliation(s)
- Valentin V Makarov
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninsky Gory, Moscow 119992, Russia
| | - Svetlana S Makarova
- Department of Biology, Lomonosov Moscow State University, Leninsky Gory, Moscow 119992, Russia
| | - Antonida V Makhotenko
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninsky Gory, Moscow 119992, Russia
| | - Ekaterina A Obraztsova
- M. M. Shemyakin and Yu. A. Ovchinnikov Bioorganic Chemistry Institute, Miklukho-Maklaya str. 16/10, Moscow 117997, Russia
| | - Natalia O Kalinina
- A. N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Leninsky Gory, Moscow 119992, Russia
| |
Collapse
|
26
|
Lukhovitskaya NI, Cowan GH, Vetukuri RR, Tilsner J, Torrance L, Savenkov EI. Importin-α-mediated nucleolar localization of potato mop-top virus TRIPLE GENE BLOCK1 (TGB1) protein facilitates virus systemic movement, whereas TGB1 self-interaction is required for cell-to-cell movement in Nicotiana benthamiana. PLANT PHYSIOLOGY 2015; 167:738-52. [PMID: 25576325 PMCID: PMC4348779 DOI: 10.1104/pp.114.254938] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 01/08/2015] [Indexed: 05/19/2023]
Abstract
Recently, it has become evident that nucleolar passage of movement proteins occurs commonly in a number of plant RNA viruses that replicate in the cytoplasm. Systemic movement of Potato mop-top virus (PMTV) involves two viral transport forms represented by a complex of viral RNA and TRIPLE GENE BLOCK1 (TGB1) movement protein and by polar virions that contain the minor coat protein and TGB1 attached to one extremity. The integrity of polar virions ensures the efficient movement of RNA-CP, which encodes the virus coat protein. Here, we report the involvement of nuclear transport receptors belonging to the importin-α family in nucleolar accumulation of the PMTV TGB1 protein and, subsequently, in the systemic movement of the virus. Virus-induced gene silencing of two importin-α paralogs in Nicotiana benthamiana resulted in significant reduction of TGB1 accumulation in the nucleus, decreasing the accumulation of the virus progeny in upper leaves and the loss of systemic movement of RNA-CP. PMTV TGB1 interacted with importin-α in N. benthamiana, which was detected by bimolecular fluorescence complementation in the nucleoplasm and nucleolus. The interaction was mediated by two nucleolar localization signals identified by bioinformatics and mutagenesis in the TGB1 amino-terminal domain. Our results showed that while TGB1 self-interaction is needed for cell-to-cell movement, importin-α-mediated nucleolar targeting of TGB1 is an essential step in establishing the efficient systemic infection of the entire plant. These results enabled the identification of two separate domains in TGB1: an internal domain required for TGB1 self-interaction and cell-to-cell movement and the amino-terminal domain required for importin-α interaction in plants, nucleolar targeting, and long-distance movement.
Collapse
Affiliation(s)
- Nina I Lukhovitskaya
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden (N.I.L., R.R.V., E.I.S.);Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom (G.H.C., J.T., L.T.); andBiomedical Sciences Research Complex, University of St. Andrews, Fife KY16 9ST, United Kingdom (J.T., L.T.)
| | - Graham H Cowan
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden (N.I.L., R.R.V., E.I.S.);Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom (G.H.C., J.T., L.T.); andBiomedical Sciences Research Complex, University of St. Andrews, Fife KY16 9ST, United Kingdom (J.T., L.T.)
| | - Ramesh R Vetukuri
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden (N.I.L., R.R.V., E.I.S.);Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom (G.H.C., J.T., L.T.); andBiomedical Sciences Research Complex, University of St. Andrews, Fife KY16 9ST, United Kingdom (J.T., L.T.)
| | - Jens Tilsner
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden (N.I.L., R.R.V., E.I.S.);Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom (G.H.C., J.T., L.T.); andBiomedical Sciences Research Complex, University of St. Andrews, Fife KY16 9ST, United Kingdom (J.T., L.T.)
| | - Lesley Torrance
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden (N.I.L., R.R.V., E.I.S.);Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom (G.H.C., J.T., L.T.); andBiomedical Sciences Research Complex, University of St. Andrews, Fife KY16 9ST, United Kingdom (J.T., L.T.)
| | - Eugene I Savenkov
- Department of Plant Biology, Uppsala BioCenter, Linnean Centre of Plant Biology, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden (N.I.L., R.R.V., E.I.S.);Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom (G.H.C., J.T., L.T.); andBiomedical Sciences Research Complex, University of St. Andrews, Fife KY16 9ST, United Kingdom (J.T., L.T.)
| |
Collapse
|
27
|
Nicaise V. Crop immunity against viruses: outcomes and future challenges. FRONTIERS IN PLANT SCIENCE 2014; 5:660. [PMID: 25484888 PMCID: PMC4240047 DOI: 10.3389/fpls.2014.00660] [Citation(s) in RCA: 182] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 11/04/2014] [Indexed: 05/02/2023]
Abstract
Viruses cause epidemics on all major cultures of agronomic importance, representing a serious threat to global food security. As strict intracellular pathogens, they cannot be controlled chemically and prophylactic measures consist mainly in the destruction of infected plants and excessive pesticide applications to limit the population of vector organisms. A powerful alternative frequently employed in agriculture relies on the use of crop genetic resistances, approach that depends on mechanisms governing plant-virus interactions. Hence, knowledge related to the molecular bases of viral infections and crop resistances is key to face viral attacks in fields. Over the past 80 years, great advances have been made on our understanding of plant immunity against viruses. Although most of the known natural resistance genes have long been dominant R genes (encoding NBS-LRR proteins), a vast number of crop recessive resistance genes were cloned in the last decade, emphasizing another evolutive strategy to block viruses. In addition, the discovery of RNA interference pathways highlighted a very efficient antiviral system targeting the infectious agent at the nucleic acid level. Insidiously, plant viruses evolve and often acquire the ability to overcome the resistances employed by breeders. The development of efficient and durable resistances able to withstand the extreme genetic plasticity of viruses therefore represents a major challenge for the coming years. This review aims at describing some of the most devastating diseases caused by viruses on crops and summarizes current knowledge about plant-virus interactions, focusing on resistance mechanisms that prevent or limit viral infection in plants. In addition, I will discuss the current outcomes of the actions employed to control viral diseases in fields and the future investigations that need to be undertaken to develop sustainable broad-spectrum crop resistances against viruses.
Collapse
Affiliation(s)
- Valérie Nicaise
- Fruit Biology and Pathology, Virology Laboratory, Institut National de la Recherche Agronomique, University of BordeauxUMR 1332, Villenave d’Ornon, France
| |
Collapse
|
28
|
Stępiński D. Functional ultrastructure of the plant nucleolus. PROTOPLASMA 2014; 251:1285-306. [PMID: 24756369 PMCID: PMC4209244 DOI: 10.1007/s00709-014-0648-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 04/08/2014] [Indexed: 05/23/2023]
Abstract
Nucleoli are nuclear domains present in almost all eukaryotic cells. They not only specialize in the production of ribosomal subunits but also play roles in many fundamental cellular activities. Concerning ribosome biosynthesis, particular stages of this process, i.e., ribosomal DNA transcription, primary RNA transcript processing, and ribosome assembly proceed in precisely defined nucleolar subdomains. Although eukaryotic nucleoli are conservative in respect of their main function, clear morphological differences between these structures can be noticed between individual kingdoms. In most cases, a plant nucleolus shows well-ordered structure in which four main ultrastructural components can be distinguished: fibrillar centers, dense fibrillar component, granular component, and nucleolar vacuoles. Nucleolar chromatin is an additional crucial structural component of this organelle. Nucleolonema, although it is not always an unequivocally distinguished nucleolar domain, has often been described as a well-grounded morphological element, especially of plant nucleoli. The ratios and morphology of particular subcompartments of a nucleolus can change depending on its metabolic activity which in turn is correlated with the physiological state of a cell, cell type, cell cycle phase, as well as with environmental influence. Precise attribution of functions to particular nucleolar subregions in the process of ribosome biosynthesis is now possible using various approaches. The presented description of plant nucleolar morphology summarizes previous knowledge regarding the function of nucleoli as well as of their particular subdomains not only in the course of ribosome biosynthesis.
Collapse
Affiliation(s)
- Dariusz Stępiński
- Department of Cytophysiology, Faculty of Biology and Environmental Protection, University of Łódź, Pomorska 141/143, 90-236, Łódź, Poland,
| |
Collapse
|
29
|
Martínez F, Daròs JA. Tobacco etch virus protein P1 traffics to the nucleolus and associates with the host 60S ribosomal subunits during infection. J Virol 2014; 88:10725-37. [PMID: 24991017 PMCID: PMC4178839 DOI: 10.1128/jvi.00928-14] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 06/30/2014] [Indexed: 12/17/2022] Open
Abstract
UNLABELLED The genus Potyvirus comprises a large group of positive-strand RNA plant viruses whose genome encodes a large polyprotein processed by three viral proteinases. P1 protein, the most amino-terminal product of the polyprotein, is an accessory factor stimulating viral genome amplification whose role during infection is not well understood. We infected plants with Tobacco etch virus (TEV; genus Potyvirus) clones in which P1 was tagged with a fluorescent protein to track its expression and subcellular localization or with an affinity tag to identify host proteins involved in complexes in which P1 also takes part during infection. Our results showed that TEV P1 exclusively accumulates in infected cells at an early stage of infection and that the protein displays a dynamic subcellular localization, trafficking in and out of the nucleus and nucleolus during infection. Inside the nucleolus, P1 particularly targets the dense granular component. Consistently, we found functional nucleolar localization and nuclear export signals in TEV P1 sequence. Our results also indicated that TEV P1 physically interacts with the host 80S cytoplasmic ribosomes and specifically binds to the 60S ribosomal subunits during infection. In vitro translation assays of reporter proteins suggested that TEV P1 stimulates protein translation, particularly when driven from the TEV internal ribosome entry site. These in vitro assays also suggested that TEV helper-component proteinase (HC-Pro) inhibits protein translation. Based on these findings, we propose that TEV P1 stimulates translation of viral proteins in infected cells. IMPORTANCE In this work, we researched the role during infection of tobacco etch virus P1 protease. P1 is the most mysterious protein of potyviruses, a relevant group of RNA viruses infecting plants. Our experiments showed that the viral P1 protein exclusively accumulates in infected cells at an early stage of infection and moves in and out of the nucleus of infected cells, particularly targeting the nucleolus. Our experiments also showed that P1 protein binds host ribosomes during infection. Based on these findings and other in vitro experiments we propose that P1 protein stimulates translation of viral proteins during infection.
Collapse
Affiliation(s)
- Fernando Martínez
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| | - José-Antonio Daròs
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Valencia, Spain
| |
Collapse
|
30
|
Solovyev AG, Savenkov EI. Factors involved in the systemic transport of plant RNA viruses: the emerging role of the nucleus. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:1689-97. [PMID: 24420565 DOI: 10.1093/jxb/ert449] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Compatible virus-host interactions depend on a suitable milieu in the host cells permitting viral gene expression, replication, and spread. During pathogenesis, viruses hijack the plant cellular machinery to access molecules, subcellular structures, and host transport pathways needed for infection. Vascular trafficking of virus transport forms (VTF) within the phloem is a crucial step in setting-up virus infection within the entire plant. Moreover, vascular trafficking is an essential step for the further transmission of the viruses by their natural vectors as movement of the viruses to the distant parts of the plant from the initial site of infection guarantees accessibility of the virus particle for vector transmission. With the recent advances in the field of plant virology several emerging themes of viral systemic movement occur linking the role of virus-mediated transcriptional reprogramming and nuclear factors in vascular trafficking. Recent studies have uncovered host factors involved in virus vascular trafficking. Surprisingly, it appears that the role of the nucleus and nuclear factors in virus movement is still under-appreciated. This review describes how these new themes started to emerge by using two contrasting modes of virus vascular trafficking. It is argued that the translocation of viral movement proteins into the nuclei is, in many cases, an essential step in promoting virus systemic infection.
Collapse
Affiliation(s)
- Andrey G Solovyev
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
| | | |
Collapse
|
31
|
Hull R. Replication of Plant Viruses. PLANT VIROLOGY 2014. [PMCID: PMC7184227 DOI: 10.1016/b978-0-12-384871-0.00007-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Viruses replicate using both their own genetic information and host cell components and machinery. The different genome types have different replication pathways which contain controls on linking the process with translation and movement around the cell as well as not compromising the infected cell. This chapter discusses the replication mechanisms, faults in replication and replication of viruses co-infecting cells. Viruses replicate using both their own genetic information and host cell components and machinery. The different genome types have different replication pathways which contain controls on linking the process with translation and movement around the cell as well as not compromising the infected cell. This chapter discusses the replication mechanisms, faults in replication and replication of viruses coinfecting cells.
Collapse
|
32
|
Shaw J, Love AJ, Makarova SS, Kalinina NO, Harrison BD, Taliansky ME. Coilin, the signature protein of Cajal bodies, differentially modulates the interactions of plants with viruses in widely different taxa. Nucleus 2014; 5:85-94. [PMID: 24637832 PMCID: PMC4028359 DOI: 10.4161/nucl.28315] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 02/18/2014] [Accepted: 02/21/2014] [Indexed: 12/28/2022] Open
Abstract
Cajal bodies (CBs) are distinct nuclear bodies physically and functionally associated with the nucleolus. In addition to their traditional function in coordinating maturation of certain nuclear RNAs, CBs participate in cell cycle regulation, development, and regulation of stress responses. A key "signature" component of CBs is coilin, the scaffolding protein essential for CB formation and function. Using an RNA silencing (loss-of-function) approach, we describe here new phenomena whereby coilin also affects, directly or indirectly, a variety of interactions between host plants and viruses that have RNA or DNA genomes. Moreover, the effects of coilin on these interactions are manifested differently: coilin contributes to plant defense against tobacco rattle virus (tobravirus), tomato black ring virus (nepovirus), barley stripe mosaic virus (hordeivirus), and tomato golden mosaic virus (begomovirus). In contrast, with potato virus Y (potyvirus) and turnip vein clearing virus (tobamovirus), coilin serves to increase virus pathogenicity. These findings show that interactions with coilin (or CBs) may involve diverse mechanisms with different viruses and that these mechanisms act at different phases of virus infection. Thus, coilin (CBs) has novel, unexpected natural functions that may be recruited or subverted by plant viruses for their own needs or, in contrast, are involved in plant defense mechanisms that suppress host susceptibility to the viruses.
Collapse
Affiliation(s)
- Jane Shaw
- Cell and Molecular Sciences; The James Hutton Institute; Dundee, UK
| | - Andrew J Love
- Cell and Molecular Sciences; The James Hutton Institute; Dundee, UK
| | - Svetlana S Makarova
- AN Belozersky Institute of Physico-Chemical Biology; Moscow State University; Moscow, Russia
| | - Natalia O Kalinina
- AN Belozersky Institute of Physico-Chemical Biology; Moscow State University; Moscow, Russia
| | - Bryan D Harrison
- Cell and Molecular Sciences; The James Hutton Institute; Dundee, UK
| | | |
Collapse
|
33
|
Salvetti A, Greco A. Viruses and the nucleolus: the fatal attraction. Biochim Biophys Acta Mol Basis Dis 2013; 1842:840-7. [PMID: 24378568 PMCID: PMC7135015 DOI: 10.1016/j.bbadis.2013.12.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/05/2013] [Accepted: 12/09/2013] [Indexed: 12/13/2022]
Abstract
Viruses are small obligatory parasites and as a consequence, they have developed sophisticated strategies to exploit the host cell's functions to create an environment that favors their own replication. A common feature of most – if not all – families of human and non-human viruses concerns their interaction with the nucleolus. The nucleolus is a multifunctional nuclear domain, which, in addition to its well-known role in ribosome biogenesis, plays several crucial other functions. Viral infection induces important nucleolar alterations. Indeed, during viral infection numerous viral components localize in nucleoli, while various host nucleolar proteins are redistributed in other cell compartments or are modified, and non-nucleolar cellular proteins reach the nucleolus. This review highlights the interactions reported between the nucleolus and some human or animal viral families able to establish a latent or productive infection, selected on the basis of their known interactions with the nucleolus and the nucleolar activities, and their links with virus replication and/or pathogenesis. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease. Most viruses interact with the nucleolus that plays a major role in virus life cycle. Virus/nucleolus interaction is crucial for virus replication and pathogenesis. Role of nucleoli in the infection with selected RNA viruses and herpes viruses
Collapse
Affiliation(s)
- Anna Salvetti
- Centre International de Recherche en Infectiologie (CIRI, International Center for Infectiology Research), Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 Allée d'Italie, 69365 Lyon CEDEX, France; LabEx Ecofect, Université de Lyon, 69007 Lyon, France.
| | - Anna Greco
- Centre International de Recherche en Infectiologie (CIRI, International Center for Infectiology Research), Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 Allée d'Italie, 69365 Lyon CEDEX, France; LabEx Ecofect, Université de Lyon, 69007 Lyon, France.
| |
Collapse
|
34
|
Park MR, Seo JK, Kim KH. Viral and nonviral elements in potexvirus replication and movement and in antiviral responses. Adv Virus Res 2013; 87:75-112. [PMID: 23809921 DOI: 10.1016/b978-0-12-407698-3.00003-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In Potato virus X, a member of the genus Potexvirus, special sequences and structures at the 5' and 3' ends of the nontranslated region function as cis-acting elements for viral replication. These elements greatly affect interactions between viral RNAs and those between viral RNAs and host factors. The potexvirus genome encodes five open-reading frames. Viral replicase, which is required for the synthesis of viral RNA, binds viral RNA elements and host factors to form a viral replication complex at the host cellular membrane. The coat protein (CP) and three viral movement proteins (TGB1, TGB2, and TGB3) have critical roles in mediating cell-to-cell viral movement through plasmodesmata by virion formation or by nonvirion ribonucleoprotein (RNP) complex formation with viral movement proteins (TGBs). The RNP complex, like TGB1-CP-viral RNA, is associated with viral replicase and used for immediate reinitiation of viral replication in newly invaded cells. Higher plants have defense mechanisms against potexviruses such as Rx-mediated resistance and RNA silencing. The CP acts as an avirulence effector for plant defense mechanisms, while TGB1 functions as a viral suppressor of RNA silencing, which is the mechanism of innate immune resistance. Here, we describe recent findings concerning the involvement of viral and host factors in potexvirus replication and in antiviral responses to potexvirus infection.
Collapse
Affiliation(s)
- Mi-Ri Park
- Department of Agricultural Biotechnology, Plant Genomics and Breeding Institute, Seoul National University, Seoul, Republic of Korea
| | | | | |
Collapse
|
35
|
Hipper C, Brault V, Ziegler-Graff V, Revers F. Viral and cellular factors involved in Phloem transport of plant viruses. FRONTIERS IN PLANT SCIENCE 2013; 4:154. [PMID: 23745125 PMCID: PMC3662875 DOI: 10.3389/fpls.2013.00154] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Accepted: 05/05/2013] [Indexed: 05/03/2023]
Abstract
Phloem transport of plant viruses is an essential step in the setting-up of a complete infection of a host plant. After an initial replication step in the first cells, viruses spread from cell-to-cell through mesophyll cells, until they reach the vasculature where they rapidly move to distant sites in order to establish the infection of the whole plant. This last step is referred to as systemic transport, or long-distance movement, and involves virus crossings through several cellular barriers: bundle sheath, vascular parenchyma, and companion cells for virus loading into sieve elements (SE). Viruses are then passively transported within the source-to-sink flow of photoassimilates and are unloaded from SE into sink tissues. However, the molecular mechanisms governing virus long-distance movement are far from being understood. While most viruses seem to move systemically as virus particles, some viruses are transported in SE as viral ribonucleoprotein complexes (RNP). The nature of the cellular and viral factors constituting these RNPs is still poorly known. The topic of this review will mainly focus on the host and viral factors that facilitate or restrict virus long-distance movement.
Collapse
Affiliation(s)
| | | | - Véronique Ziegler-Graff
- Laboratoire Propre du CNRS (UPR 2357), Virologie Végétale, Institut de Biologie Moléculaire des Plantes, Université de StrasbourgStrasbourg, France
| | - Frédéric Revers
- UMR 1332 de Biologie du Fruit et Pathologie, INRA, Université de BordeauxVillenave d’Ornon, France
| |
Collapse
|
36
|
Deng X, Kelloniemi J, Haikonen T, Vuorinen AL, Elomaa P, Teeri TH, Valkonen JPT. Modification of Tobacco rattle virus RNA1 to serve as a VIGS vector reveals that the 29K movement protein is an RNA silencing suppressor of the virus. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:503-14. [PMID: 23360458 DOI: 10.1094/mpmi-12-12-0280-r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Tobacco rattle virus (TRV) has a bipartite, positive-sense single-stranded RNA genome and is widely used for virus-induced gene silencing (VIGS) in plants. RNA1 of TRV that lacks the gene for the cysteine-rich 16K silencing-suppression protein infects plants systemically in the absence of RNA2. Here, we attempted to engineer RNA1 for use as a VIGS vector by inserting heterologous gene fragments to replace 16K. The RNA1 vector systemically silenced the phytoene desaturase (PDS) gene, although less efficiently than when the original VIGS vector system was used, which consists of wild-type RNA1 and engineered RNA2 carrying the heterologous gene. Infectious RNA1 mutants with a dysfunctional 16K suppressed silencing and enhanced transgene expression in green fluorescent protein-transgenic Nicotiana benthamiana following inoculation by agroinfiltration, unlike mutants that also lacked 29K, a movement protein (MP) gene. The 30K MP gene of Tobacco mosaic virus complemented in cis the movement defect but not the silencing suppression functions of TRV 29K. Silencing suppression by 29K occurred in the context of RNA1 replication but not in an agroinfiltration assay which tested 29K alone for suppression of sense-mediated silencing. Both 29K and 16K were needed to avoid necrotic symptoms in RNA1-infected N. benthamiana. The results shed new light on virulence factors of TRV.
Collapse
Affiliation(s)
- Xianbao Deng
- Department of Agricultural Sciences, University of Helsinki, Finland
| | | | | | | | | | | | | |
Collapse
|
37
|
Ruiz-Ruiz S, Soler N, Sánchez-Navarro J, Fagoaga C, López C, Navarro L, Moreno P, Peña L, Flores R. Citrus tristeza virus p23: determinants for nucleolar localization and their influence on suppression of RNA silencing and pathogenesis. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:306-18. [PMID: 23387469 DOI: 10.1094/mpmi-08-12-0201-r] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Citrus tristeza virus (CTV) encodes a singular protein (p23, 209 amino acids) with multiple functions, including RNA silencing suppression (RSS). Confocal laser-scanning microscopy of green fluorescent protein (GFP)-p23 agroexpressed in Nicotiana benthamiana revealed its accumulation in the nucleolus, Cajal bodies, and plasmodesmata. To dissect the nucleolar localization signal (NoLS) typically associated with basic motifs, seven truncated and 10 point-mutated versions of p23 were assayed. Deletion mutants showed that regions 50 to 86 and 100 to 157 (excluding fragment 106 to 114), both with basic motifs and the first with a zinc-finger, contain the (bipartite) NoLS. Alanine substitutions delimited this signal to three cysteines of the Zn-finger and some basic amino acids. RSS activity of p23 in N. benthamiana was abolished by essentially all mutants, indicating that it involves most p23 regions. The necrotic-inducing ability of p23 when launched in N. benthamiana from Potato virus X was only retained by deletion mutant 158-209 and one substitution mutant, showing that the Zn-finger and flanking basic motifs form part of the pathogenic determinant. Ectopic expression of p23 and some deletion mutants in transgenic Mexican lime demarcated a similar determinant, suggesting that p23 affects related pathways in citrus and N. benthamiana. Both RSS activity and pathogenicity of p23 appear related to its nucleolar localization.
Collapse
Affiliation(s)
- Susana Ruiz-Ruiz
- Consejo Superior de Investigaciones Cientificas-Universidad Politecnica de Valencia, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Dynamic localization of two tobamovirus ORF6 proteins involves distinct organellar compartments. J Gen Virol 2013; 94:230-240. [DOI: 10.1099/vir.0.045278-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
ORF6 is a small gene that overlaps the movement and coat protein genes of subgroup 1a tobamoviruses. The ORF6 protein of tomato mosaic virus (ToMV) strain L (L-ORF6), interacts in vitro with eukaryotic elongation factor 1α, and mutation of the ORF6 gene of tobacco mosaic virus (TMV) strain U1 (U1-ORF6) reduces the pathogenicity in vivo of TMV, whereas expression of this gene from two other viruses, tobacco rattle virus (TRV) and potato virus X (PVX), increases their pathogenicity. In this work, the in vivo properties of the L-ORF6 and U1-ORF6 proteins were compared to identify sequences that direct the proteins to different subcellular locations and also influence virus pathogenicity. Site-specific mutations in the ORF6 protein were made, hybrid ORF6 proteins were created in which the N-terminal and C-terminal parts were derived from the two proteins, and different subregions of the protein were examined, using expression either from a recombinant TRV vector or as a yellow fluorescent protein fusion from a binary plasmid in Agrobacterium tumefaciens. L-ORF6 caused mild necrotic symptoms in Nicotiana benthamiana when expressed from TRV, whereas U1-ORF6 caused severe symptoms including death of the plant apex. The difference in symptoms was associated with the C-terminal region of L-ORF6, which directed the protein to the endoplasmic reticulum (ER), whereas U1-ORF6 was directed initially to the nucleolus and later to the mitochondria. Positively charged residues at the N terminus allowed nucleolar entry of both U1-ORF6 and L-ORF6, but hydrophobic residues at the C terminus of L-ORF6 directed this protein to the ER.
Collapse
|
39
|
Lin MH, Sivakumaran H, Apolloni A, Wei T, Jans DA, Harrich D. Nullbasic, a potent anti-HIV tat mutant, induces CRM1-dependent disruption of HIV rev trafficking. PLoS One 2012; 7:e51466. [PMID: 23251541 PMCID: PMC3519632 DOI: 10.1371/journal.pone.0051466] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 11/02/2012] [Indexed: 12/30/2022] Open
Abstract
Nullbasic, a mutant of the HIV-1 Tat protein, has anti-HIV-1 activity through mechanisms that include inhibition of Rev function and redistribution of the HIV-1 Rev protein from the nucleolus to the nucleoplasm and cytoplasm. Here we investigate the mechanism of this effect for the first time, establishing that redistribution of Rev by Nullbasic is not due to direct interaction between the two proteins. Rather, Nullbasic affects subcellular localization of cellular proteins that regulate Rev trafficking. In particular, Nullbasic induced redistribution of exportin 1 (CRM1), nucleophosmin (B23) and nucleolin (C23) from the nucleolus to the nucleus when Rev was coexpressed, but never in its absence. Inhibition of the Rev:CRM1 interaction by leptomycin B or a non-interacting RevM10 mutant completely blocked redistribution of Rev by Nullbasic. Finally, Nullbasic did not inhibit importin β- or transportin 1-mediated nuclear import, suggesting that cytoplasmic accumulation of Rev was due to increased export by CRM1. Overall, our data support the conclusion that CRM1-dependent subcellular redistribution of Rev from the nucleolus by Nullbasic is not through general perturbation of either nuclear import or export. Rather, Nullbasic appears to interact with and disrupt specific components of a Rev trafficking complex required for its nucleocytoplasmic shuttling and, in particular, its nucleolar accumulation.
Collapse
Affiliation(s)
- Min-Hsuan Lin
- Queensland Institute of Medical Research, Molecular Virology Laboratory, Herston, Brisbane, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Queensland, Australia
| | - Haran Sivakumaran
- Queensland Institute of Medical Research, Molecular Virology Laboratory, Herston, Brisbane, Australia
| | - Ann Apolloni
- Queensland Institute of Medical Research, Molecular Virology Laboratory, Herston, Brisbane, Australia
| | - Ting Wei
- Queensland Institute of Medical Research, Molecular Virology Laboratory, Herston, Brisbane, Australia
| | - David A. Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - David Harrich
- Queensland Institute of Medical Research, Molecular Virology Laboratory, Herston, Brisbane, Australia
| |
Collapse
|
40
|
Gao R, Liu P, Wong SM. Identification of a plant viral RNA genome in the nucleus. PLoS One 2012; 7:e48736. [PMID: 23155403 PMCID: PMC3498252 DOI: 10.1371/journal.pone.0048736] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 09/28/2012] [Indexed: 01/04/2023] Open
Abstract
Viruses contain either DNA or RNA as genomes. DNA viruses replicate within nucleus, while most RNA viruses, especially (+)-sense single-stranded RNA, replicate and are present within cytoplasm. We proposed a new thought that is contrary to the common notion that (+)-sense single-stranded RNA viruses are present only in the cytoplasm. In this study, we question whether the genome of a plant RNA virus (non-retroviral) is present in the nucleus of infected cells? Hibiscus chlorotic ringspot virus (HCRSV) RNA was detected in the nucleus of infected cells, as shown by fluorescent in situ hybridization. Western blot using anti-histone 3 and anti-phosphoenolpyruvate carboxylase showed that nuclei were highly purified from mock and HCRSV-infected kenaf (Hibiscus cannabilis L.) leaves, respectively. The p23 and HCRSV coat protein (CP) coding regions were both amplified from total RNA extracted from isolated nuclei. Viral RNA in the nucleus may be used to generate viral microRNAs (vir-miRNAs), as five putative vir-miRNAs were predicted from HCRSV using the vir-miRNAs prediction database. The vir-miRNA (hcrsv-miR-H1-5p) was detected using TaqMan® stem-loop real-time PCR, and by northern blot using DIG-end labeled probe in HCRSV-infected kenaf leaves. Finally, a novel nuclear localization signal (NLS) was discovered in p23 of HCRSV. The NLS interacts with importin α and facilitates viral RNA genome to enter nucleus. We demonstrate the presence of a (+)-sense single-stranded viral RNA within nucleus.
Collapse
Affiliation(s)
- Ruimin Gao
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Peng Liu
- Temasek Life Sciences Laboratory, Singapore
| | - Sek-Man Wong
- Department of Biological Sciences, National University of Singapore, Singapore
- Temasek Life Sciences Laboratory, Singapore
- * E-mail:
| |
Collapse
|
41
|
Herranz MC, Pallas V, Aparicio F. Multifunctional roles for the N-terminal basic motif of Alfalfa mosaic virus coat protein: nucleolar/cytoplasmic shuttling, modulation of RNA-binding activity, and virion formation. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:1093-103. [PMID: 22746826 DOI: 10.1094/mpmi-04-12-0079-r] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In addition to virion formation, the coat protein (CP) of Alfalfa mosaic virus (AMV) is involved in the regulation of replication and translation of viral RNAs, and in cell-to-cell and systemic movement of the virus. An intriguing feature of the AMV CP is its nuclear and nucleolar accumulation. Here, we identify an N-terminal lysine-rich nucleolar localization signal (NoLS) in the AMV CP required to both enter the nucleus and accumulate in the nucleolus of infected cells, and a C-terminal leucine-rich domain which might function as a nuclear export signal. Moreover, we demonstrate that AMV CP interacts with importin-α, a component of the classical nuclear import pathway. A mutant AMV RNA 3 unable to target the nucleolus exhibited reduced plus-strand RNA synthesis and cell-to-cell spread. Moreover, virion formation and systemic movement were completely abolished in plants infected with this mutant. In vitro analysis demonstrated that specific lysine residues within the NoLS are also involved in modulating CP-RNA binding and CP dimerization, suggesting that the NoLS represents a multifunctional domain within the AMV CP. The observation that nuclear and nucleolar import signals mask RNA-binding properties of AMV CP, essential for viral replication and translation, supports a model in which viral expression is carefully modulated by a cytoplasmic/nuclear balance of CP accumulation.
Collapse
Affiliation(s)
- Mari Carmen Herranz
- Department of Molecular and Evolutionary Plant Virology, Instituto de Biologia Molecular y Celular de Plantas, Valencia, Spain
| | | | | |
Collapse
|
42
|
Semashko MA, Rakitina DV, González I, Canto T, Kalinina NO, Taliansky ME. Movement protein of hordeivirus interacts in vitro and in vivo with coilin, a major structural protein of Cajal bodies. DOKL BIOCHEM BIOPHYS 2012; 442:57-60. [PMID: 22419098 DOI: 10.1134/s1607672912010164] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Indexed: 12/18/2022]
Affiliation(s)
- M A Semashko
- Belozersky Institute of Physico-Chemical Biology and Biological Faculty of Lomonosov Moscow State University, Moscow, Russia
| | | | | | | | | | | |
Collapse
|
43
|
Semashko MA, González I, Shaw J, Leonova OG, Popenko VI, Taliansky ME, Canto T, Kalinina NO. The extreme N-terminal domain of a hordeivirus TGB1 movement protein mediates its localization to the nucleolus and interaction with fibrillarin. Biochimie 2012; 94:1180-8. [PMID: 22349738 DOI: 10.1016/j.biochi.2012.02.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 02/06/2012] [Indexed: 01/13/2023]
Abstract
The hordeiviral movement protein encoded by the first gene of the triple gene block (TGBp1) of Poa semilatent virus (PSLV), interacts with viral genomic RNAs to form RNP particles which are considered to be a form of viral genome capable of cell-to-cell and long-distance transport in infected plants. The PSLV TGBp1 contains a C-terminal NTPase/helicase domain (HELD) and an N-terminal extension region consisting of two structurally and functionally distinct domains: an extreme N-terminal domain (NTD) and an internal domain (ID). This study demonstrates that transient expression of TGBp1 fused to GFP in Nicotiana benthamiana leaves results in faint but obvious fluorescence in the nucleolus in addition to cytosolic distribution. Mutagenesis of the basic amino acids inside the NTD clusters A (116)KSKRKKKNKK(125) and B (175)KKATKKESKKQTK(187) reveals that these clusters are indispensable for nuclear and nucleolar targeting of PSLV TGBp1 and may contain nuclear and nucleolar localization signals or their elements. The PSLV TGBp1 is able to bind to fibrillarin, the major nucleolar protein (AtFib2 from Arabidopsis thaliana) in vitro. This protein-protein interaction occurs between the glycine-arginine-rich (GAR) domain of fibrillarin and the first 82 amino acid residues of TGBp1. The interaction of TGBp1 with fibrillarin is also visualized in vivo by bimolecular fluorescence complementation (BiFC) during co-expression of TGBp1 or its deletion mutants, and fibrillarin as fusions to different halves of YFP in N. benthamiana plants. The sites responsible for nuclear/nucleolar localization and fibrillarin binding, have been located within the intrinsically disordered TGBp1 NTD. These data could suggest that specific functions of hordeivirus TGBp1 may depend on its interaction with nucleolar components.
Collapse
Affiliation(s)
- Maria A Semashko
- A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Leninsky Gory, Moscow, 119992, Russia
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Solovyev AG, Kalinina NO, Morozov SY. Recent advances in research of plant virus movement mediated by triple gene block. FRONTIERS IN PLANT SCIENCE 2012; 3:276. [PMID: 23248633 PMCID: PMC3520053 DOI: 10.3389/fpls.2012.00276] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 11/23/2012] [Indexed: 05/19/2023]
Abstract
The aim of this short review was to summarize recent advances in the field of viral cell-to-cell movement mediated by the triple gene block (TGB). The growing body of new research has uncovered links between virus cell-to-cell trafficking and replication, silencing suppression, virus spread over the plant, as well as suggested the roles of nucleus/nucleolus in plant virus transport and revealed protein-membrane associations occurring during subcellular targeting and cell-to-cell movement. In this context, our review briefly summarized current views on several potentially important functions of TGB proteins and on the development of new experimental systems that improved understanding of the molecular events during TGB-mediated virus movement.
Collapse
Affiliation(s)
- Andrey G. Solovyev
- Belozersky Institute of Physico-Chemical Biology, Moscow State UniversityMoscow, Russia
| | - Natalia O. Kalinina
- Belozersky Institute of Physico-Chemical Biology, Moscow State UniversityMoscow, Russia
| | - Sergey Y. Morozov
- Belozersky Institute of Physico-Chemical Biology, Moscow State UniversityMoscow, Russia
- *Correspondence: Sergey Y. Morozov, Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119992, Russia. e-mail:
| |
Collapse
|
45
|
Shaw P, Brown J. Nucleoli: composition, function, and dynamics. PLANT PHYSIOLOGY 2012; 158:44-51. [PMID: 22082506 PMCID: PMC3252080 DOI: 10.1104/pp.111.188052] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 11/12/2011] [Indexed: 05/18/2023]
Affiliation(s)
- Peter Shaw
- Department of Cell and Developmental Biology, John Innes Center, Norwich NR4 7UH, United Kingdom.
| | | |
Collapse
|
46
|
Jiang J, Laliberté JF. The genome-linked protein VPg of plant viruses-a protein with many partners. Curr Opin Virol 2011; 1:347-54. [PMID: 22440836 DOI: 10.1016/j.coviro.2011.09.010] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 09/23/2011] [Accepted: 09/26/2011] [Indexed: 12/19/2022]
Abstract
For some plant positive-sense RNA viruses, a protein known as VPg (short for virus protein, genome linked) is covalently linked to the 5' end of the viral RNA. The VPg is an intrinsically disordered protein, and this property would confer an ability to bind several proteins. Accordingly, the potyvirus VPg interacts with many proteins, notably host factors involved in protein synthesis within viral replication factories or within the nucleus. The number of protein partners, the clustering of the various interactions centering around it, the biological importance for some of these interactions (e.g. VPg-eIF4E) and the intrinsically disordered state of the protein are all elements that support the notion that VPg is a hub protein that controls many processes leading to virus production and spread.
Collapse
Affiliation(s)
- Jun Jiang
- Institut National de la Recherche Scientifique, Institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Québec, Canada H7V 1B7
| | | |
Collapse
|
47
|
Rakitina DV, Taliansky M, Brown JWS, Kalinina NO. Two RNA-binding sites in plant fibrillarin provide interactions with various RNA substrates. Nucleic Acids Res 2011; 39:8869-80. [PMID: 21785141 PMCID: PMC3203579 DOI: 10.1093/nar/gkr594] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Fibrillarin, one of the major proteins of the nucleolus, plays several essential roles in ribosome biogenesis including pre-rRNA processing and 2′-O-ribose methylation of rRNA and snRNAs. Recently, it has been shown that fibrillarin plays a role in virus infections and is associated with viral RNPs. Here, we demonstrate the ability of recombinant fibrillarin 2 from Arabidopsis thaliana (AtFib2) to interact with RNAs of different lengths and types including rRNA, snoRNA, snRNA, siRNA and viral RNAs in vitro. Our data also indicate that AtFib2 possesses two RNA-binding sites in the central (138–179 amino acids) and C-terminal (225–281 amino acids) parts of the protein, respectively. The conserved GCVYAVEF octamer does not bind RNA directly as suggested earlier, but may assist with the proper folding of the central RNA-binding site.
Collapse
Affiliation(s)
- D. V. Rakitina
- Department of Virology and A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119991, Russia, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK and Plant Sciences Division, University of Dundee, DD2 5DA, UK
| | - Michael Taliansky
- Department of Virology and A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119991, Russia, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK and Plant Sciences Division, University of Dundee, DD2 5DA, UK
- *To whom correspondence should be addressed. Tel: +44(0)1382562731; Fax: +44 (0)1382 562426;
| | - J. W. S. Brown
- Department of Virology and A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119991, Russia, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK and Plant Sciences Division, University of Dundee, DD2 5DA, UK
| | - N. O. Kalinina
- Department of Virology and A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119991, Russia, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK and Plant Sciences Division, University of Dundee, DD2 5DA, UK
| |
Collapse
|
48
|
Vaccinia virus F16 protein, a predicted catalytically inactive member of the prokaryotic serine recombinase superfamily, is targeted to nucleoli. Virology 2011; 417:334-42. [PMID: 21752417 PMCID: PMC3163719 DOI: 10.1016/j.virol.2011.06.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Revised: 06/11/2011] [Accepted: 06/17/2011] [Indexed: 11/24/2022]
Abstract
The F16L gene of vaccinia virus (VACV) is conserved in all chordopoxviruses except avipoxviruses. The crocodile poxvirus F16 protein ortholog has highly significant similarity to prokaryotic serine recombinases and contains all amino acids that comprise the catalytic site. In contrast, F16 orthologs encoded by other poxviruses show only marginally significant similarity to serine recombinases, lack essential amino acids of the active site and are most likely inactive derivatives of serine recombinases. Nevertheless, the conservation of F16L in non-avian poxviruses suggested an important function. However, a VACV mutant with the F16L gene knocked out replicated normally in dividing and quiescent cells. The F16 protein was synthesized early after infection and detected in virus cores. When expressed in infected or uninfected cells, F16 accumulated in nucleoli depending on the level of expression and confluency of cells. Evidence was obtained that F16 forms multimers, which might regulate concentration-dependent intracellular localization.
Collapse
|