1
|
Guo J, Wang G, Xie L, Wang X, Feng L, Guo W, Tao X, Humbel BM, Zhang Z, Hong J. Three-dimensional analysis of membrane structures associated with tomato spotted wilt virus infection. PLANT, CELL & ENVIRONMENT 2023; 46:650-664. [PMID: 36482792 PMCID: PMC10107360 DOI: 10.1111/pce.14511] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 11/28/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
To study viral infection, the direct structural visualization of the viral life cycle consisting of virus attachment, entry, replication, assembly and transport is essential. Although conventional electron microscopy (EM) has been extremely helpful in the investigation of virus-host cell interactions, three-dimensional (3D) EM not only provides important information at the nanometer resolution, but can also create 3D maps of large volumes, even entire virus-infected cells. Here, we determined the ultrastructural details of tomato spotted wilt virus (TSWV)-infected plant cells using focused ion beam scanning EM (FIB-SEM). The viral morphogenesis and dynamic transformation of paired parallel membranes (PPMs) were analyzed. The endoplasmic reticulum (ER) membrane network consisting of tubules and sheets was related to viral intracellular trafficking and virion storage. Abundant lipid-like bodies, clustering mitochondria, cell membrane tubules, and myelin-like bodies were likely associated with viral infection. Additionally, connecting structures between neighboring cells were found only in infected plant tissues and showed the characteristics of tubular structure. These novel connections that formed continuously in the cell wall or were wrapped by the cell membranes of neighboring cells appeared frequently in the large-scale 3D model, suggesting additional strategies for viral trafficking that were difficult to distinguish using conventional EM.
Collapse
Affiliation(s)
- Jiansheng Guo
- Department of Pathology of Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhouChina
- Center of Cryo‐Electron MicroscopyZhejiang University School of MedicineHangzhouChina
| | - Guan Wang
- Center of Cryo‐Electron MicroscopyZhejiang University School of MedicineHangzhouChina
| | - Li Xie
- Center of Analysis and MeasurementZhejiang UniversityHangzhouChina
| | - Xinqiu Wang
- Center of Analysis and MeasurementZhejiang UniversityHangzhouChina
| | - Lingchong Feng
- Center of Cryo‐Electron MicroscopyZhejiang University School of MedicineHangzhouChina
| | - Wangbiao Guo
- Center of Cryo‐Electron MicroscopyZhejiang University School of MedicineHangzhouChina
| | - Xiaorong Tao
- Department of Plant PathologyNanjing Agricultural UniversityNanjingChina
| | - Bruno M. Humbel
- Center of Cryo‐Electron MicroscopyZhejiang University School of MedicineHangzhouChina
- Imaging, Okinawa Institute of Science and Technology (OIST)OkinawaJapan
| | - Zhongkai Zhang
- Yunnan Provincial Key Laboratory of Agri‐Biotechnology, Institute of Biotechnology and Genetic ResourcesYunnan Academy of Agricultural SciencesKunmingChina
| | - Jian Hong
- Center of Analysis and MeasurementZhejiang UniversityHangzhouChina
| |
Collapse
|
2
|
Alcaide C, Donaire L, Aranda MA. Transcriptome analyses unveiled differential regulation of AGO and DCL genes by pepino mosaic virus strains. MOLECULAR PLANT PATHOLOGY 2022; 23:1592-1607. [PMID: 35852033 PMCID: PMC9562736 DOI: 10.1111/mpp.13249] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 06/21/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Pepino mosaic virus (PepMV) is a single-stranded (ss), positive-sense (+) RNA potexvirus that affects tomato crops worldwide. We have described an in planta antagonistic interaction between PepMV isolates of two strains in which the EU isolate represses the accumulation of the CH2 isolate during mixed infections. Reports describing transcriptomic responses to mixed infections are scant. We carried out transcriptomic analyses of tomato plants singly and mixed-infected with two PepMV isolates of both strains. Comparison of the transcriptomes of singly infected plants showed that deeper transcriptomic alterations occurred at early infection times, and also that each of the viral strains modulated the host transcriptome differentially. Mixed infections caused transcriptomic alterations similar to those for the sum of single infections at early infection times, but clearly differing at later times postinfection. We next tested the hypothesis that PepMV-EU, in either single or mixed infections, deregulates host gene expression differentially so that virus accumulation of both strains gets repressed. That seemed to be the case for the genes AGO1a, DCL2d, AGO2a, and DCL2b, which are involved in the antiviral silencing pathway and were upregulated by PepMV-EU but not by PepMV-CH2 at early times postinfection. The pattern of AGO2a expression was validated by reverse transcription-quantitative PCR in tomato and Nicotiana benthamiana plants. Using an N. benthamiana ago2 mutant line, we showed that AGO2 indeed plays an important role in the antiviral defence against PepMV, but it is not the primary determinant of the outcome of the antagonistic interaction between the two PepMV strains.
Collapse
Affiliation(s)
- Cristina Alcaide
- Department of Stress Biology and Plant PathologyCentro de Edafología y Biología Aplicada del Segura‐CSICMurciaSpain
| | - Livia Donaire
- Department of Stress Biology and Plant PathologyCentro de Edafología y Biología Aplicada del Segura‐CSICMurciaSpain
| | - Miguel A. Aranda
- Department of Stress Biology and Plant PathologyCentro de Edafología y Biología Aplicada del Segura‐CSICMurciaSpain
| |
Collapse
|
3
|
Solovyev AG, Atabekova AK, Lezzhov AA, Solovieva AD, Chergintsev DA, Morozov SY. Distinct Mechanisms of Endomembrane Reorganization Determine Dissimilar Transport Pathways in Plant RNA Viruses. PLANTS 2022; 11:plants11182403. [PMID: 36145804 PMCID: PMC9504206 DOI: 10.3390/plants11182403] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/02/2022] [Accepted: 09/13/2022] [Indexed: 11/22/2022]
Abstract
Plant viruses exploit the endomembrane system of infected cells for their replication and cell-to-cell transport. The replication of viral RNA genomes occurs in the cytoplasm in association with reorganized endomembrane compartments induced by virus-encoded proteins and is coupled with the virus intercellular transport via plasmodesmata that connect neighboring cells in plant tissues. The transport of virus genomes to and through plasmodesmata requires virus-encoded movement proteins (MPs). Distantly related plant viruses encode different MP sets, or virus transport systems, which vary in the number of MPs and their properties, suggesting their functional differences. Here, we discuss two distinct virus transport pathways based on either the modification of the endoplasmic reticulum tubules or the formation of motile vesicles detached from the endoplasmic reticulum and targeted to endosomes. The viruses with the movement proteins encoded by the triple gene block exemplify the first, and the potyviral system is the example of the second type. These transport systems use unrelated mechanisms of endomembrane reorganization. We emphasize that the mode of virus interaction with cell endomembranes determines the mechanism of plant virus cell-to-cell transport.
Collapse
Affiliation(s)
- Andrey G. Solovyev
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
- All-Russia Research Institute of Agricultural Biotechnology, 127550 Moscow, Russia
| | - Anastasia K. Atabekova
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Alexander A. Lezzhov
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
| | - Anna D. Solovieva
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Denis A. Chergintsev
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
| | - Sergey Y. Morozov
- A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia
- Department of Virology, Biological Faculty, Moscow State University, 119234 Moscow, Russia
- Correspondence: ; Tel.: +7-(495)-939-31-98
| |
Collapse
|
4
|
Peña EJ, Heinlein M. In Vivo Visualization of Mobile mRNA Particles in Plants Using BglG. Methods Mol Biol 2022; 2457:411-426. [PMID: 35349157 DOI: 10.1007/978-1-0716-2132-5_28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cells have developed mechanisms for cytoplasmic RNA transport and localization that participate in the regulation and subcellular localization of protein synthesis. In addition, plants can exchange RNA molecules between cells through plasmodesmata and to distant tissues in the phloem. These mechanisms are hijacked by RNA viruses to establish their replication complexes and to disseminate their genomes throughout the plant organism with the help of virus-encoded movement proteins (MP). Live imaging of RNA molecules is a fundamental approach to understand the regulation and molecular basis of these processes. The most widely used experimental systems for the in vivo visualization of genetically encoded RNA molecules are based on fluorescently tagged RNA binding proteins that bind to specific motifs inserted into the RNA, thus allowing the tracking of the specific RNA molecule by fluorescent microscopy. Recently, we developed the use of the E. coli RNA binding protein BglG for the imaging of RNAs tagged with BglG-binding sites in planta. We describe here the detailed method by which we use this in vivo RNA tagging system for the real-time imaging of Tobacco mosaic virus (TMV) MP mRNA.
Collapse
Affiliation(s)
- Eduardo J Peña
- Instituto de Biotecnología y Biología Molecular (IBBM), Facultad de Ciencias Exactas-UNLP, CONICET, La Plata, Argentina
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes (IBMP), CNRS, Université de Strasbourg, Strasbourg, France.
| |
Collapse
|
5
|
Huang C, Heinlein M. Function of Plasmodesmata in the Interaction of Plants with Microbes and Viruses. Methods Mol Biol 2022; 2457:23-54. [PMID: 35349131 DOI: 10.1007/978-1-0716-2132-5_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Plasmodesmata (PD) are gated plant cell wall channels that allow the trafficking of molecules between cells and play important roles during plant development and in the orchestration of cellular and systemic signaling responses during interactions of plants with the biotic and abiotic environment. To allow gating, PD are equipped with signaling platforms and enzymes that regulate the size exclusion limit (SEL) of the pore. Plant-interacting microbes and viruses target PD with specific effectors to enhance their virulence and are useful probes to study PD functions.
Collapse
Affiliation(s)
- Caiping Huang
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes, CNRS, Université de Strasbourg, Strasbourg, France.
| |
Collapse
|
6
|
Wang Y, Wang G, Bai J, Zhang Y, Wang Y, Wen S, Li L, Yang Z, Hong N. A novel Actinidia cytorhabdovirus characterized using genomic and viral protein interaction features. MOLECULAR PLANT PATHOLOGY 2021; 22:1271-1287. [PMID: 34288324 PMCID: PMC8435229 DOI: 10.1111/mpp.13110] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
A novel cytorhabdovirus, tentatively named Actinidia virus D (AcVD), was identified from kiwifruit (Actinidia chinensis) in China using high-throughput sequencing technology. The genome of AcVD consists of 13,589 nucleotides and is organized into seven open reading frames (ORFs) in its antisense strand, coding for proteins in the order N-P-P3-M-G-P6-L. The ORFs were flanked by a 3' leader sequence and a 5' trailer sequence and are separated by conserved intergenic junctions. The genome sequence of AcVD was 44.6%-51.5% identical to those of reported cytorhabdoviruses. The proteins encoded by AcVD shared the highest sequence identities, ranging from 27.3% (P6) to 44.5% (L), with the respective proteins encoded by reported cytorhabdoviruses. Phylogenetic analysis revealed that AcVD clustered together with the cytorhabdovirus Wuhan insect virus 4. The subcellular locations of the viral proteins N, P, P3, M, G, and P6 in epidermal cells of Nicotiana benthamiana leaves were determined. The M protein of AcVD uniquely formed filament structures and was associated with microtubules. Bimolecular fluorescence complementation assays showed that three proteins, N, P, and M, self-interact, protein N plays a role in the formation of cytoplasm viroplasm, and protein M recruits N, P, P3, and G to microtubules. In addition, numerous paired proteins interact in the nucleus. This study presents the first evidence of a cytorhabdovirus infecting kiwifruit plants and full location and interaction maps to gain insight into viral protein functions.
Collapse
Affiliation(s)
- Yanxiang Wang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Horticultural Crop (Fruit Trees) Biology and Germplasm Creation of the Ministry of AgricultureHuazhong Agricultural UniversityWuhanChina
| | - Guoping Wang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Horticultural Crop (Fruit Trees) Biology and Germplasm Creation of the Ministry of AgricultureHuazhong Agricultural UniversityWuhanChina
| | - Jianyu Bai
- Laboratory of Fruit Trees DiseaseInstitute of Economic ForestryXinjiang Academy of Forestry SciencesUrumqiChina
| | - Yongle Zhang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Ying Wang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Shaohua Wen
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Liu Li
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Zuokun Yang
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
| | - Ni Hong
- Key Laboratory of Plant Pathology of Hubei ProvinceCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Horticultural Crop (Fruit Trees) Biology and Germplasm Creation of the Ministry of AgricultureHuazhong Agricultural UniversityWuhanChina
| |
Collapse
|
7
|
James AM, Seal SE, Bailey AM, Foster GD. Viral inosine triphosphatase: A mysterious enzyme with typical activity, but an atypical function. MOLECULAR PLANT PATHOLOGY 2021; 22:382-389. [PMID: 33471956 PMCID: PMC7865087 DOI: 10.1111/mpp.13021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 05/03/2023]
Abstract
Plant viruses typically have highly condensed genomes, yet the plant-pathogenic viruses Cassava brown streak virus, Ugandan cassava brown streak virus, and Euphorbia ringspot virus are unusual in encoding an enzyme not yet found in any other virus, the "house-cleaning" enzyme inosine triphosphatase. Inosine triphosphatases (ITPases) are highly conserved enzymes that occur in all kingdoms of life and perform a house-cleaning function by hydrolysing the noncanonical nucleotide inosine triphosphate to inosine monophosphate. The ITPases encoded by cassava brown streak virus and Ugandan cassava brown streak virus have been characterized biochemically and are shown to have typical ITPase activity. However, their biological role in virus infection has yet to be elucidated. Here we review what is known of viral-encoded ITPases and speculate on potential roles in infection with the aim of generating a greater understanding of cassava brown streak viruses, a group of the world's most devastating viruses.
Collapse
Affiliation(s)
- Amy M. James
- School of Biological SciencesLife Sciences BuildingUniversity of BristolBristolUK
| | - Susan E. Seal
- Natural Resources Institute, Chatham MaritimeGillinghamUK
| | - Andy M. Bailey
- School of Biological SciencesLife Sciences BuildingUniversity of BristolBristolUK
| | - Gary D. Foster
- School of Biological SciencesLife Sciences BuildingUniversity of BristolBristolUK
| |
Collapse
|
8
|
Amari K, Huang C, Heinlein M. Potential Impact of Global Warming on Virus Propagation in Infected Plants and Agricultural Productivity. FRONTIERS IN PLANT SCIENCE 2021; 12:649768. [PMID: 33868349 PMCID: PMC8045756 DOI: 10.3389/fpls.2021.649768] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/03/2021] [Indexed: 05/14/2023]
Abstract
The increasing pace of global warming and climate instability will challenge the management of pests and diseases of cultivated plants. Several reports have shown that increases in environmental temperature can enhance the cell-to-cell and systemic propagation of viruses within their infected hosts. These observations suggest that earlier and longer periods of warmer weather may cause important changes in the interaction between viruses and their host's plants, thus posing risks of new viral diseases and outbreaks in agriculture and the wild. As viruses target plasmodesmata (PD) for cell-to-cell spread, these cell wall pores may play yet unknown roles in the temperature-sensitive regulation of intercellular communication and virus infection. Understanding the temperature-sensitive mechanisms in plant-virus interactions will provide important knowledge for protecting crops against diseases in a warmer climate.
Collapse
|
9
|
Peña EJ, Robles Luna G, Heinlein M. In vivo imaging of tagged mRNA in plant tissues using the bacterial transcriptional antiterminator BglG. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:271-282. [PMID: 33098198 DOI: 10.1111/tpj.15035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 09/18/2020] [Indexed: 06/11/2023]
Abstract
RNA transport and localization represent important post-transcriptional mechanisms to determine the subcellular localization of protein synthesis. Plants have the capacity to transport messenger (m)RNA molecules beyond the cell boundaries through plasmodesmata and over long distances in the phloem. RNA viruses exploit these transport pathways to disseminate their infections and represent important model systems to investigate RNA transport in plants. Here, we present an in vivo plant RNA-labeling system based on the Escherichia coli RNA-binding protein BglG. Using the detection of RNA in mobile RNA particles formed by viral movement protein (MP) as a model, we demonstrate the efficiency and specificity of mRNA detection by the BglG system as compared with MS2 and λN systems. Our observations show that MP mRNA is specifically associated with MP in mobile MP particles but hardly with MP localized at plasmodesmata. MP mRNA is clearly absent from MP accumulating along microtubules. We show that the in vivo BglG labeling of the MP particles depends on the presence of the BglG-binding stem-loop aptamers within the MP mRNA and that the aptamers enhance the coprecipitation of BglG by MP, thus demonstrating the presence of an MP:MP mRNA complex. The BglG system also allowed us to monitor the cell-to-cell transport of the MP mRNA, thus linking the observation of mobile MP mRNA granules with intercellular MP mRNA transport. Given its specificity demonstrated here, the BglG system may be widely applicable for studying mRNA transport and localization in plants.
Collapse
Affiliation(s)
- Eduardo J Peña
- Université de Strasbourg, CNRS, IBMP UPR 2357, Strasbourg, F-67000, France
- Instituto de Biotecnología y Biología Molecular (IBBM), Facultad de Ciencias Exactas, CONICET UNLP, La Plata, Argentina
| | - Gabriel Robles Luna
- Instituto de Biotecnología y Biología Molecular (IBBM), Facultad de Ciencias Exactas, CONICET UNLP, La Plata, Argentina
| | - Manfred Heinlein
- Université de Strasbourg, CNRS, IBMP UPR 2357, Strasbourg, F-67000, France
| |
Collapse
|
10
|
Abstract
The modern view of the mechanism of intercellular movement of viruses is based largely on data from the study of the tobacco mosaic virus (TMV) 30-kDa movement protein (MP). The discovered properties and abilities of TMV MP, namely, (a) in vitro binding of single-stranded RNA in a non-sequence-specific manner, (b) participation in the intracellular trafficking of genomic RNA to the plasmodesmata (Pd), and (c) localization in Pd and enhancement of Pd permeability, have been used as a reference in the search and analysis of candidate proteins from other plant viruses. Nevertheless, although almost four decades have passed since the introduction of the term “movement protein” into scientific circulation, the mechanism underlying its function remains unclear. It is unclear why, despite the absence of homology, different MPs are able to functionally replace each other in trans-complementation tests. Here, we consider the complexity and contradictions of the approaches for assessment of the ability of plant viral proteins to perform their movement function. We discuss different aspects of the participation of MP and MP/vRNA complexes in intra- and intercellular transport. In addition, we summarize the essential MP properties for their functioning as “conditioners”, creating a favorable environment for viral reproduction.
Collapse
|
11
|
Sheshukova EV, Ershova NM, Kamarova KA, Dorokhov YL, Komarova TV. The Tobamoviral Movement Protein: A "Conditioner" to Create a Favorable Environment for Intercellular Spread of Infection. FRONTIERS IN PLANT SCIENCE 2020; 11:959. [PMID: 32670343 PMCID: PMC7328123 DOI: 10.3389/fpls.2020.00959] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
During their evolution, viruses acquired genes encoding movement protein(s) (MPs) that mediate the intracellular transport of viral genetic material to plasmodesmata (Pd) and initiate the mechanisms leading to the increase in plasmodesmal permeability. Although the current view on the role of the viral MPs was primarily formed through studies on tobacco mosaic virus (TMV), the function of its MP has not been fully elucidated. Given the intercellular movement of MPs independent of genomic viral RNA (vRNA), this characteristic may induce favorable conditions ahead of the infection front for the accelerated movement of the vRNA (i.e. the MP plays a role as a "conditioner" of viral intercellular spread). This idea is supported by (a) the synthesis of MP from genomic vRNA early in infection, (b) the Pd opening and the MP transfer to neighboring cells without formation of the viral replication complex (VRC), and (c) the MP-mediated movement of VRCs beyond the primary infected cell. Here, we will consider findings that favor the TMV MP as a "conditioner" of enhanced intercellular virus movement. In addition, we will discuss the mechanism by which TMV MP opens Pd for extraordinary transport of macromolecules. Although there is no evidence showing direct effects of TMV MP on Pd leading to their dilatation, recent findings indicate that MPs exert their influence indirectly by modulating Pd external and structural macromolecules such as callose and Pd-associated proteins. In explaining this phenomenon, we will propose a mechanism for TMV MP functioning as a conditioner for virus movement.
Collapse
Affiliation(s)
| | - Natalia M. Ershova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Kamila A. Kamarova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | - Yuri L. Dorokhov
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Tatiana V. Komarova
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| |
Collapse
|
12
|
Peña EJ, Heinlein M. Visualization of Transiently Expressed mRNA in Plants Using MS2. Methods Mol Biol 2020; 2166:103-120. [PMID: 32710405 DOI: 10.1007/978-1-0716-0712-1_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
RNA transport and localization are evolutionarily conserved processes that allow protein translation to occur at specific subcellular sites and thereby having fundamental roles in the determination of cell fates, embryonic patterning, asymmetric cell division, and cell polarity. In addition to localizing RNA molecules to specific subcellular sites, plants have the ability to exchange RNA molecules between cells through plasmodesmata (PD). Plant RNA viruses hijack the mechanisms of intracellular and intercellular RNA transport to establish localized replication centers within infected cells and then to disseminate their infectious genomes between cells and throughout the plant organism with the help of their movement proteins (MP). In this chapter, we describe the transient expression of the tobacco mosaic virus movement protein (TMV-MP) and the application of the MS2 system for the in vivo labeling of the MP-encoding mRNA. The MS2 method is based on the binding of the bacteriophage coat protein (CP) to its origin of assembly (OAS) in the phage RNA. Thus, to label a specific mRNA in vivo, a tandem repetition of a 19-nucleotide-long stem-loop (SL) sequence derived from the MS2 OAS sequence (MSL) is transcriptionally fused to the RNA under investigation. The RNA is detected by the co-expression of fluorescent protein-tagged MS2 CP (MCP), which binds to each of the MSL elements. In providing a detailed protocol for the in vivo visualization of TMV-MP mRNA tagged with the MS2 system in Nicotiana benthamiana epidermal cells, we describe (1) the specific DNA constructs, (2) Agrobacterium tumefaciens-mediated transfection for their transient expression in plants, and (3) imaging conditions required to obtain high-quality mRNA imaging data.
Collapse
Affiliation(s)
- Eduardo José Peña
- Instituto de Biotecnología y Biología Molecular, CCT-La Plata CONICET, Fac. Cs. Exactas, U.N.L.P, La Plata, Argentina
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France.
| |
Collapse
|
13
|
Reagan BC, Burch-Smith TM. Viruses Reveal the Secrets of Plasmodesmal Cell Biology. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:26-39. [PMID: 31715107 DOI: 10.1094/mpmi-07-19-0212-fi] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Plasmodesmata (PD) are essential for intercellular trafficking of molecules required for plant life, from small molecules like sugars and ions to macromolecules including proteins and RNA molecules that act as signals to regulate plant development and defense. As obligate intracellular pathogens, plant viruses have evolved to manipulate this communication system to facilitate the initial cell-to-cell and eventual systemic spread in their plant hosts. There has been considerable interest in how viruses manipulate the PD that connect the protoplasts of neighboring cells, and viruses have yielded invaluable tools for probing the structure and function of PD. With recent advances in biochemistry and imaging, we have gained new insights into the composition and structure of PD in the presence and absence of viruses. Here, we first discuss viral strategies for manipulating PD for their intercellular movement and examine how this has shed light on our understanding of native PD function. We then address the controversial role of the cytoskeleton in trafficking to and through PD. Finally, we address how viruses could alter PD structure and consider possible mechanisms of the phenomenon described as 'gating'. This discussion supports the significance of virus research in elucidating the properties of PD, these persistently enigmatic plant organelles.
Collapse
Affiliation(s)
- Brandon C Reagan
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, U.S.A
| | - Tessa M Burch-Smith
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, U.S.A
| |
Collapse
|
14
|
Liu Y, Huang C, Zeng J, Yu H, Li Y, Yuan C. Identification of two additional plasmodesmata localization domains in the tobacco mosaic virus cell-to-cell-movement protein. Biochem Biophys Res Commun 2019; 521:145-151. [PMID: 31629470 DOI: 10.1016/j.bbrc.2019.10.093] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 10/10/2019] [Indexed: 11/17/2022]
Abstract
Despite decades of intensive studies, the failure to identify plasmodesmata (PD) localization sequences has constrained our understanding of Tobacco mosaic virus (TMV) movement. Recently, we identified the first PD localization signal (major PLS) in the TMV movement protein (MP), which encompasses the first 50 amino acid residues of the MP. Although the major PLS is sufficient for PD targeting, the efficiency is lower than the full-length TMV MP. To address this efficiency gap, we identified two additional PLS domains encompassing amino acid residues 61 to 80, and 147 to 170 of the MP and showed that these two domains target to PD, but do not transit to adjacent cells. We also demonstrated that the MP61-80 fragment interacts with Arabidopsis synaptotagmin A, which was also shown to interact with the major TMV MP PLS. Therefore, our findings have provided new insights to more fully understand the mechanism underlying plasmodesmal targeting of TMV MP.
Collapse
Affiliation(s)
- Yong Liu
- Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Science, Kunming, Yunnan, 650201, China
| | - Changjun Huang
- Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Science, Kunming, Yunnan, 650201, China
| | - Jianmin Zeng
- Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Science, Kunming, Yunnan, 650201, China
| | - Haiqin Yu
- Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Science, Kunming, Yunnan, 650201, China
| | - Yongping Li
- Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Science, Kunming, Yunnan, 650201, China
| | - Cheng Yuan
- Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Science, Kunming, Yunnan, 650201, China.
| |
Collapse
|
15
|
Abstract
Plant viruses cross the barrier of the plant cell wall by moving through intercellular channels, termed plasmodesmata, to invade their hosts. They accomplish this by encoding movement proteins (MPs), which act to alter plasmodesmal gating. How MPs target to plasmodesmata is not well understood. Our recent characterization of the first plasmodesmal localization signal (PLS) identified in a viral MP, namely, the MP encoded by the Tobamovirus Tobacco mosaic virus (TMV), now provides the opportunity to identify host proteins that recognize this PLS and may be important for its plasmodesmal targeting. One such candidate protein is Arabidopsis synaptotagmin A (SYTA), which is required to form endoplasmic reticulum (ER)-plasma membrane contact sites and regulates the MP-mediated trafficking of begomoviruses, tobamoviruses, and potyviruses. In particular, SYTA interacts with, and regulates the cell-to-cell transport of, both TMV MP and the MP encoded by the Tobamovirus Turnip vein clearing virus (TVCV). Using in planta bimolecular fluorescence complementation (BiFC) and yeast two-hybrid assays, we show here that the TMV PLS interacted with SYTA. This PLS sequence was both necessary and sufficient for interaction with SYTA, and the plasmodesmal targeting activity of the TMV PLS was substantially reduced in an Arabidopsis syta knockdown line. Our findings show that SYTA is one host factor that can recognize the TMV PLS and suggest that this interaction may stabilize the association of TMV MP with plasmodesmata.IMPORTANCE Plant viruses use their movement proteins (MPs) to move through host intercellular connections, plasmodesmata. Perhaps one of the most intriguing, yet least studied, aspects of this transport is the MP signal sequences and their host recognition factors. Recently, we have described the plasmodesmal localization signal (PLS) of the Tobacco mosaic virus (TMV) MP. Here, we identified the Arabidopsis synaptotagmin A (SYTA) as a host factor that recognizes TMV MP PLS and promotes its association with the plasmodesmal membrane. The significance of these findings is two-fold: (i) we identified the TMV MP association with the cell membrane at plasmodesmata as an important PLS-dependent step in plasmodesmal targeting, and (ii) we identified the plant SYTA protein that specifically recognizes PLS as a host factor involved in this step.
Collapse
|
16
|
Lei R, Du Z, Kong J, Li G, He Y, Qiu Y, Yan J, Zhu S. Blue Native/SDS-PAGE and iTRAQ-Based Chloroplasts Proteomics Analysis of Nicotiana tabacum Leaves Infected with M Strain of Cucumber Mosaic Virus Reveals Several Proteins Involved in Chlorosis Symptoms. Proteomics 2018; 18. [PMID: 29193783 DOI: 10.1002/pmic.201700359] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 11/16/2017] [Indexed: 01/05/2023]
Abstract
Virus infection in plants involves necrosis, chlorosis, and mosaic. The M strain of cucumber mosaic virus (M-CMV) has six distinct symptoms: vein clearing, mosaic, chlorosis, partial green recovery, complete green recovery, and secondary mosaic. Chlorosis indicates the loss of chlorophyll which is highly abundant in plant leaves and plays essential roles in photosynthesis. Blue native/SDS-PAGE combined with mass spectrum was performed to detect the location of virus, and proteomic analysis of chloroplast isolated from virus-infected plants was performed to quantify the changes of individual proteins in order to gain a global view of the total chloroplast protein dynamics during the virus infection. Among the 438 proteins quantified, 33 showed a more than twofold change in abundance, of which 22 are involved in the light-dependent reactions and five in the Calvin cycle. The dynamic change of these proteins indicates that light-dependent reactions are down-accumulated, and the Calvin cycle was up-accumulated during virus infection. In addition to the proteins involved in photosynthesis, tubulin was up-accumulated in virus-infected plant, which might contribute to the autophagic process during plant infection. In conclusion, this extensive proteomic investigation on intact chloroplasts of virus-infected tobacco leaves provided some important novel information on chlorosis mechanisms induced by virus infection.
Collapse
Affiliation(s)
- Rong Lei
- Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
| | - Zhixin Du
- Guangxi Entry-Exit Inspection and Quarantine Bureau, Nanning, Guangxi, P. R. China
| | - Jun Kong
- Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
| | - Guifen Li
- Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
| | - Yan He
- Animal and Plant and Food Testing Center, Tianjin Entry Exit Inspection and Quarantine Bureau, Tianjin, P. R. China
| | - Yanhong Qiu
- Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
| | - Jin Yan
- Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
| | - Shuifang Zhu
- Institute of Plant Quarantine, Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
| |
Collapse
|
17
|
Pitzalis N, Heinlein M. The roles of membranes and associated cytoskeleton in plant virus replication and cell-to-cell movement. JOURNAL OF EXPERIMENTAL BOTANY 2017; 69:117-132. [PMID: 29036578 DOI: 10.1093/jxb/erx334] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The infection of plants by viruses depends on cellular mechanisms that support the replication of the viral genomes, and the cell-to-cell and systemic movement of the virus via plasmodesmata (PD) and the connected phloem. While the propagation of some viruses requires the conventional endoplasmic reticulum (ER)-Golgi pathway, others replicate and spread between cells in association with the ER and are independent of this pathway. Using selected viruses as examples, this review re-examines the involvement of membranes and the cytoskeleton during virus infection and proposes potential roles of class VIII myosins and membrane-tethering proteins in controlling viral functions at specific ER subdomains, such as cortical microtubule-associated ER sites, ER-plasma membrane contact sites, and PD.
Collapse
|
18
|
Kozieł E, Bujarski JJ, Otulak K. Molecular Biology of Prune Dwarf Virus-A Lesser Known Member of the Bromoviridae but a Vital Component in the Dynamic Virus-Host Cell Interaction Network. Int J Mol Sci 2017; 18:E2733. [PMID: 29258199 PMCID: PMC5751334 DOI: 10.3390/ijms18122733] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 11/21/2017] [Accepted: 12/13/2017] [Indexed: 12/29/2022] Open
Abstract
Prune dwarf virus (PDV) is one of the members of Bromoviridae family, genus Ilarvirus. Host components that participate in the regulation of viral replication or cell-to-cell movement via plasmodesmata are still unknown. In contrast, viral infections caused by some other Bromoviridae members are well characterized. Bromoviridae can be distinguished based on localization of their replication process in infected cells, cell-to-cell movement mechanisms, and plant-specific response reactions. Depending upon the genus, "genome activation" and viral replication are linked to various membranous structures ranging from endoplasmic reticulum, to tonoplast. In the case of PDV, there is still no evidence of natural resistance sources in the host plants susceptible to virus infection. Apparently, PDV has a great ability to overcome the natural defense responses in a wide spectrum of plant hosts. The first manifestations of PDV infection are specific cell membrane alterations, and the formation of replicase complexes that support PDV RNA replication inside the spherules. During each stage of its life cycle, the virus uses cell components to replicate and to spread in whole plants, within the largely suppressed cellular immunity environment. This work presents the above stages of the PDV life cycle in the context of current knowledge about other Bromoviridae members.
Collapse
Affiliation(s)
- Edmund Kozieł
- Department of Botany, Faculty of Agriculture and Biology, Warsaw University of Life Sciences-SGGW, Nowoursynowska Street 159, 02-776 Warsaw, Poland.
| | - Józef J Bujarski
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA.
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland.
| | - Katarzyna Otulak
- Department of Botany, Faculty of Agriculture and Biology, Warsaw University of Life Sciences-SGGW, Nowoursynowska Street 159, 02-776 Warsaw, Poland.
| |
Collapse
|
19
|
Schwan S, Ludtka C, Friedmann A, Cismak A, Berthold L, Goehre F, Kiesow A, Heilmann A. Morphological Characterization of the Self-Assembly of Virus Movement Proteins into Nanotubes in the Absence of Virus Particles. ACTA ACUST UNITED AC 2017; 1:e1700113. [PMID: 32646158 DOI: 10.1002/adbi.201700113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/02/2017] [Indexed: 11/11/2022]
Abstract
One infection mechanism of plant viruses is the generation of nanotubes by viral movement proteins, allowing cell-to-cell virus particle transport. Previously, it was assumed that viral nanotubes extend directly from the host-cell plasma membrane. In virus-infected plants, these nanotubes reach an extraordinary diameter:length ratio (≈100 nm:µm or mm range). Here, viral nanotubes are produced in a transient protoplast system; the coding sequence for alfalfa mosaic virus movement protein is translationally fused to green fluorescent protein. The maximum extension of viral nanotubes into the culture medium is achieved 24-48 h posttransfection, with lengths in the micro- and millimeter ranges. Scanning electron microscopy and transmission electron microscopy show that strong inhomogeneous viral nanotubes are formed compared to particle-filled systems. The nanotubes have similar length, but fluctuating wall thickness and diameter and are susceptible to entanglement and recombination. Indirect methods demonstrate that movement proteins assemble independently at the top of the nanotube. These viral nanotubes grow distinctly from previously known natural particle-filled systems and are a unique biological tubular nanomaterial that has the potential for micro- or nanoapplications as a mechanically stable structural component.
Collapse
Affiliation(s)
- Stefan Schwan
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany.,Karlsruhe Institute of Technology, Institute for Applied Materials Computational Materials Science IAM-CMS, 76131, Karlsruhe, Germany
| | - Christopher Ludtka
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany.,Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, 37996, USA
| | - Andrea Friedmann
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany
| | - Andreas Cismak
- Center for Applied Microstructure Diagnostics, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany
| | - Lutz Berthold
- Center for Applied Microstructure Diagnostics, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany
| | - Felix Goehre
- Department of Neurosurgery, University of Helsinki and Helsinki University Hospital, Helsinki, 00260, Finland
| | - Andreas Kiesow
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany
| | - Andreas Heilmann
- Department of Biological and Macromolecular Materials, Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Halle, 06120, Germany
| |
Collapse
|
20
|
Krapp S, Schuy C, Greiner E, Stephan I, Alberter B, Funk C, Marschall M, Wege C, Bailer SM, Kleinow T, Krenz B. Begomoviral Movement Protein Effects in Human and Plant Cells: Towards New Potential Interaction Partners. Viruses 2017; 9:E334. [PMID: 29120369 PMCID: PMC5707541 DOI: 10.3390/v9110334] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 11/03/2017] [Accepted: 11/07/2017] [Indexed: 01/07/2023] Open
Abstract
Geminiviral single-stranded circular DNA genomes replicate in nuclei so that the progeny DNA has to cross both the nuclear envelope and the plasmodesmata for systemic spread within plant tissues. For intra- and intercellular transport, two proteins are required: a nuclear shuttle protein (NSP) and a movement protein (MP). New characteristics of ectopically produced Abutilon mosaic virus (AbMV) MP (MPAbMV), either authentically expressed or fused to a yellow fluorescent protein or epitope tags, respectively, were determined by localization studies in mammalian cell lines in comparison to plant cells. Wild-type MPAbMV and the distinct MPAbMV: reporter protein fusions appeared as curled threads throughout mammalian cells. Co-staining with cytoskeleton markers for actin, intermediate filaments, or microtubules identified these threads as re-organized microtubules. These were, however, not stabilized by the viral MP, as demonstrated by nocodazole treatment. The MP of a related bipartite New World begomovirus, Cleome leaf crumple virus (ClLCrV), resulted in the same intensified microtubule bundling, whereas that of a nanovirus did not. The C-terminal section of MPAbMV, i.e., the protein's oligomerization domain, was dispensable for the effect. However, MP expression in plant cells did not affect the microtubules network. Since plant epidermal cells are quiescent whilst mammalian cells are proliferating, the replication-associated protein RepAbMV protein was then co-expressed with MPAbMV to induce cell progression into S-phase, thereby inducing distinct microtubule bundling without MP recruitment to the newly formed threads. Co-immunoprecipitation of MPAbMV in the presence of RepAbMV, followed by mass spectrometry identified potential novel MPAbMV-host interaction partners: the peptidyl-prolyl cis-trans isomerase NIMA-interacting 4 (Pin4) and stomatal cytokinesis defective 2 (SCD2) proteins. Possible roles of these putative interaction partners in the begomoviral life cycle and cytoskeletal association modes are discussed.
Collapse
Affiliation(s)
- Susanna Krapp
- Department Biologie, Lehrstuhl Biochemie, Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany.
| | - Christian Schuy
- Department Biologie, Lehrstuhl Biochemie, Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany.
| | - Eva Greiner
- Department Biologie, Lehrstuhl Biochemie, Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany.
| | - Irina Stephan
- Abteilung Molekularbiologie und Virologie der Pflanzen, Institut für Biomaterialien und Biomolekulare Systeme, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
| | - Barbara Alberter
- Abteilung Molekularbiologie und Virologie der Pflanzen, Institut für Biomaterialien und Biomolekulare Systeme, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
| | - Christina Funk
- Institute for Interfacial Engineering and Plasma Technology IGVP, Universität Stuttgart, Nobelstrasse 12, 70569 Stuttgart, Germany.
| | - Manfred Marschall
- Institute for Clinical and Molecular Virology, Universität Erlangen-Nürnberg, 91054 Erlangen, Germany.
| | - Christina Wege
- Abteilung Molekularbiologie und Virologie der Pflanzen, Institut für Biomaterialien und Biomolekulare Systeme, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
| | - Susanne M Bailer
- Institute for Interfacial Engineering and Plasma Technology IGVP, Universität Stuttgart, Nobelstrasse 12, 70569 Stuttgart, Germany.
| | - Tatjana Kleinow
- Abteilung Molekularbiologie und Virologie der Pflanzen, Institut für Biomaterialien und Biomolekulare Systeme, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
| | - Björn Krenz
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Inhoffenstr. 7 B, 38124 Braunschweig, Germany.
| |
Collapse
|
21
|
Qiao W, Medina V, Falk BW. Inspirations on Virus Replication and Cell-to-Cell Movement from Studies Examining the Cytopathology Induced by Lettuce infectious yellows virus in Plant Cells. FRONTIERS IN PLANT SCIENCE 2017; 8:1672. [PMID: 29021801 PMCID: PMC5623981 DOI: 10.3389/fpls.2017.01672] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 09/12/2017] [Indexed: 05/06/2023]
Abstract
Lettuce infectious yellows virus (LIYV) is the type member of the genus Crinivirus in the family Closteroviridae. Like many other positive-strand RNA viruses, LIYV infections induce a number of cytopathic changes in plant cells, of which the two most characteristic are: Beet yellows virus-type inclusion bodies composed of vesicles derived from cytoplasmic membranes; and conical plasmalemma deposits (PLDs) located at the plasmalemma over plasmodesmata pit fields. The former are not only found in various closterovirus infections, but similar structures are known as 'viral factories' or viroplasms in cells infected with diverse types of animal and plant viruses. These are generally sites of virus replication, virion assembly and in some cases are involved in cell-to-cell transport. By contrast, PLDs induced by the LIYV-encoded P26 non-virion protein are not involved in replication but are speculated to have roles in virus intercellular movement. These deposits often harbor LIYV virions arranged to be perpendicular to the plasma membrane over plasmodesmata, and our recent studies show that P26 is required for LIYV systemic plant infection. The functional mechanism of how LIYV P26 facilitates intercellular movement remains unclear, however, research on other plant viruses provides some insights on the possible ways of viral intercellular movement through targeting and modifying plasmodesmata via interactions between plant cellular components and viral-encoded factors. In summary, beginning with LIYV, we review the studies that have uncovered the biological determinants giving rise to these cytopathological effects and their importance in viral replication, virion assembly and intercellular movement during the plant infection by closteroviruses, and compare these findings with those for other positive-strand RNA viruses.
Collapse
Affiliation(s)
- Wenjie Qiao
- Department of Plant Pathology, University of California, Davis, Davis, CA, United States
| | - Vicente Medina
- Department of Crop and Forest Sciences, University of Lleida, Lleida, Spain
| | - Bryce W. Falk
- Department of Plant Pathology, University of California, Davis, Davis, CA, United States
| |
Collapse
|
22
|
Yuan C, Lazarowitz SG, Citovsky V. Identification of Plasmodesmal Localization Sequences in Proteins In Planta. J Vis Exp 2017:55301. [PMID: 28829412 PMCID: PMC5614340 DOI: 10.3791/55301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Plasmodesmata (Pd) are cell-to-cell connections that function as gateways through which small and large molecules are transported between plant cells. Whereas Pd transport of small molecules, such as ions and water, is presumed to occur passively, cell-to-cell transport of biological macromolecules, such proteins, most likely occurs via an active mechanism that involves specific targeting signals on the transported molecule. The scarcity of identified plasmodesmata (Pd) localization signals (PLSs) has severely restricted the understanding of protein-sorting pathways involved in plant cell-to-cell macromolecular transport and communication. From a wealth of plant endogenous and viral proteins known to traffic through Pd, only three PLSs have been reported to date, all of them from endogenous plant proteins. Thus, it is important to develop a reliable and systematic experimental strategy to identify a functional PLS sequence, that is both necessary and sufficient for Pd targeting, directly in the living plant cells. Here, we describe one such strategy using as a paradigm the cell-to-cell movement protein (MP) of the Tobacco mosaic virus (TMV). These experiments, that identified and characterized the first plant viral PLS, can be adapted for discovery of PLS sequences in most Pd-targeted proteins.
Collapse
Affiliation(s)
- Cheng Yuan
- Department of Biochemistry and Cell Biology, State University of New York;
| | | | - Vitaly Citovsky
- Department of Biochemistry and Cell Biology, State University of New York
| |
Collapse
|
23
|
Abstract
Microtubules (MTs) form a rapidly adaptable network of filaments that radiate throughout the cell. These dynamic arrays facilitate a wide range of cellular processes, including the capture, transport, and spatial organization of cargos and organelles, as well as changes in cell shape, polarity, and motility. Nucleating from MT-organizing centers, including but by no means limited to the centrosome, MTs undergo rapid transitions through phases of growth, pause, and catastrophe, continuously exploring and adapting to the intracellular environment. Subsets of MTs can become stabilized in response to environmental cues, acquiring distinguishing posttranslational modifications and performing discrete functions as specialized tracks for cargo trafficking. The dynamic behavior and organization of the MT array is regulated by MT-associated proteins (MAPs), which include a subset of highly specialized plus-end-tracking proteins (+TIPs) that respond to signaling cues to alter MT behavior. As pathogenic cargos, viruses require MTs to transport to and from their intracellular sites of replication. While interactions with and functions for MT motor proteins are well characterized and extensively reviewed for many viruses, this review focuses on MT filaments themselves. Changes in the spatial organization and dynamics of the MT array, mediated by virus- or host-induced changes to MT regulatory proteins, not only play a central role in the intracellular transport of virus particles but also regulate a wider range of processes critical to the outcome of infection.
Collapse
|
24
|
Hong JS, Ju HJ. The Plant Cellular Systems for Plant Virus Movement. THE PLANT PATHOLOGY JOURNAL 2017; 33:213-228. [PMID: 28592941 PMCID: PMC5461041 DOI: 10.5423/ppj.rw.09.2016.0198] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 11/05/2016] [Accepted: 11/13/2016] [Indexed: 05/24/2023]
Abstract
Plasmodesmata (PDs) are specialized intercellular channels that facilitate the exchange of various molecules, including sugars, ribonucleoprotein complexes, transcription factors, and mRNA. Their diameters, estimated to be 2.5 nm in the neck region, are too small to transfer viruses or viral genomes. Tobacco mosaic virus and Potexviruses are the most extensively studied viruses. In viruses, the movement protein (MP) is responsible for the PD gating that allows the intercellular movement of viral genomes. Various host factors interact with MP to regulate complicated mechanisms related to PD gating. Virus replication and assembly occur in viral replication complex (VRC) with membrane association, especially in the endoplasmic reticulum. VRC have a highly organized structure and are highly regulated by interactions among the various host factors, proteins encoded by the viral genome, and the viral genome. Virus trafficking requires host machineries, such as the cytoskeleton and the secretory systems. MP facilitates the virus replication and movement process. Despite the current level of understanding of virus movement, there are still many unknown and complex interactions between virus replication and virus movement. While numerous studies have been conducted to understand plant viruses with regards to cell-to-cell movement and replication, there are still many knowledge gaps. To study these interactions, adequate research tools must be used such as molecular, and biochemical techniques. Without such tools, virologists will not be able to gain an accurate or detailed understanding of the virus infection process.
Collapse
Affiliation(s)
- Jin-Sung Hong
- Department of Applied Biology, College of Agriculture and Life Sciences, Kangwon National University, Chuncheon 24341, Korea
| | - Ho-Jong Ju
- Department of Agricultural Biology, College of Agricultural Life Science, Chonbuk National University, Jeonju 54896, Korea
- Plant Medicinal Research Center, College of Agricultural Life Science, Chonbuk National University, Jeonju 54896, Korea
| |
Collapse
|
25
|
Chen Y, Bi H, Li X, Zhang Z, Yue H, Weng S, He J. Wsv023 interacted with Litopenaeus vannamei γ-tubulin complex associated proteins 2, and decreased the formation of microtubules. ROYAL SOCIETY OPEN SCIENCE 2017; 4:160379. [PMID: 28484601 PMCID: PMC5414238 DOI: 10.1098/rsos.160379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 03/23/2017] [Indexed: 06/07/2023]
Abstract
A previous study found the key transcription factor of Litopenaeus vannamei PERK-eIF2α pathway cyclic AMP-dependent transcription factor 4 (LvATF4) was involved in the transcriptional regulation of white spot syndrome virus (WSSV) gene wsv023. Knocked-down expression of LvATF4 reduced the viral copy number and the cumulative mortality of WSSV-infected shrimp. These results suggested that wsv023 may be critical to WSSV infection but the precise function of wsv023 was still unknown. By using co-immunoprecipitation and pull-down assays, we show that wsv023 interacts with L. vannamei gamma complex-associated protein 2 (LvGCP2), which is the core protein of the γ-tubulin small complex. Knocked-down, the wsv023 gene significantly reduced the copy number of WSSV in L. vannamei muscle, as well as the cumulative mortality of infected shrimp. And PERK-eIF2α pathway inhibition also showed reduced virus copy number and abrogated shrimp mortality. Furthermore, overexpression of wsv023 inhibited the formation of microtubules in 293T cells. Flow cytometry revealed that WSSV infection similarly decreased the formation of microtubules in L. vannamei haemocytes. These findings suggested that wsv023 plays a role in microtubule organization in host cells, which in turn may be beneficial to WSSV.
Collapse
Affiliation(s)
- Yihong Chen
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, South China Sea Bio-Resource Exploitation and Protection Collaborative Innovation Center (SCS-REPIC), School of Marine Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- State Key Laboratory for Biocontrol, OE Key Laboratory of Aquatic Product Safety, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
| | - Haitao Bi
- School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- State Key Laboratory for Biocontrol, OE Key Laboratory of Aquatic Product Safety, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
| | - Xiaoyun Li
- Fisheries College, Guangdong Ocean University, Zhanjiang, People's Republic of China
| | - Zezhi Zhang
- School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- State Key Laboratory for Biocontrol, OE Key Laboratory of Aquatic Product Safety, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
| | - Haitao Yue
- School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- State Key Laboratory for Biocontrol, OE Key Laboratory of Aquatic Product Safety, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
| | - Shaoping Weng
- School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- State Key Laboratory for Biocontrol, OE Key Laboratory of Aquatic Product Safety, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
| | - Jianguo He
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, South China Sea Bio-Resource Exploitation and Protection Collaborative Innovation Center (SCS-REPIC), School of Marine Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
- State Key Laboratory for Biocontrol, OE Key Laboratory of Aquatic Product Safety, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, People's Republic of China
| |
Collapse
|
26
|
Abstract
Intracellular trafficking and asymmetric localization of RNA molecules within cells are a prevalent process across phyla involved in developmental control and signaling and thus in the determination of cell fate. In addition to intracellular localization, plants support the trafficking of RNA molecules also between cells through plasmodesmata (PD), which has important roles in the cell-to-cell and systemic communication during plant growth and development. Viruses have developed strategies to exploit the underlying plant RNA transport mechanisms for the cell-to-cell and systemic dissemination of infection. In vivo RNA visualization methods have revolutionized the study of RNA dynamics in living cells. However, their application in plants is still in its infancy. To gain insights into the RNA transport mechanisms in plants, we study the localization and transport of Tobacco mosaic virus RNA using MS2 tagging. This technique involves the tagging of the RNA of interest with repeats of an RNA stem-loop (SL) that is derived from the origin of assembly of the bacteriophage MS2 and recruits the MS2 coat protein (MCP). Thus, expression of MCP fused to a fluorescent marker allows the specific visualization of the SL-carrying RNA. Here we describe a detailed protocol for Agrobacterium tumefaciens-mediated transient expression and in vivo visualization of MS2-tagged mRNAs in Nicotiana benthamiana leaves.
Collapse
Affiliation(s)
- E J Peña
- Instituto de Biotecnología y Biología Molecular, CCT-La Plata CONICET, Fac. Cs. Exactas, U.N.L.P., La Plata, Argentina
| | - M Heinlein
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France.
| |
Collapse
|
27
|
Yuan C, Lazarowitz SG, Citovsky V. Identification of a Functional Plasmodesmal Localization Signal in a Plant Viral Cell-To-Cell-Movement Protein. mBio 2016; 7:e02052-15. [PMID: 26787834 PMCID: PMC4725018 DOI: 10.1128/mbio.02052-15] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 12/07/2015] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED Our fundamental knowledge of the protein-sorting pathways required for plant cell-to-cell trafficking and communication via the intercellular connections termed plasmodesmata has been severely limited by the paucity of plasmodesmal targeting sequences that have been identified to date. To address this limitation, we have identified the plasmodesmal localization signal (PLS) in the Tobacco mosaic virus (TMV) cell-to-cell-movement protein (MP), which has emerged as the paradigm for dissecting the molecular details of cell-to-cell transport through plasmodesmata. We report here the identification of a bona fide functional TMV MP PLS, which encompasses amino acid residues between positions 1 and 50, with residues Val-4 and Phe-14 potentially representing critical sites for PLS function that most likely affect protein conformation or protein interactions. We then demonstrated that this PLS is both necessary and sufficient for protein targeting to plasmodesmata. Importantly, as TMV MP traffics to plasmodesmata by a mechanism that is distinct from those of the three plant cell proteins in which PLSs have been reported, our findings provide important new insights to expand our understanding of protein-sorting pathways to plasmodesmata. IMPORTANCE The science of virology began with the discovery of Tobacco mosaic virus (TMV). Since then, TMV has served as an experimental and conceptual model for studies of viruses and dissection of virus-host interactions. Indeed, the TMV cell-to-cell-movement protein (MP) has emerged as the paradigm for dissecting the molecular details of cell-to-cell transport through the plant intercellular connections termed plasmodesmata. However, one of the most fundamental and key functional features of TMV MP, its putative plasmodesmal localization signal (PLS), has not been identified. Here, we fill this gap in our knowledge and identify the TMV MP PLS.
Collapse
Affiliation(s)
- Cheng Yuan
- Department of Biochemistry and Cell Biology, State University of New York at Stony Brook, Stony Brook, New York, USA
| | - Sondra G Lazarowitz
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, USA
| | - Vitaly Citovsky
- Department of Biochemistry and Cell Biology, State University of New York at Stony Brook, Stony Brook, New York, USA
| |
Collapse
|
28
|
Plant virus replication and movement. Virology 2015; 479-480:657-71. [DOI: 10.1016/j.virol.2015.01.025] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 01/19/2015] [Accepted: 01/28/2015] [Indexed: 01/10/2023]
|
29
|
Abstract
The symplastic communication network established by plasmodesmata (PD) and connected phloem provides an essential pathway for spatiotemporal intercellular signaling in plant development but is also exploited by viruses for moving their genomes between cells in order to infect plants systemically. Virus movement depends on virus-encoded movement proteins (MPs) that target PD and therefore represent important keys to the cellular mechanisms underlying the intercellular trafficking of viruses and other macromolecules. Viruses and their MPs have evolved different mechanisms for intracellular transport and interaction with PD. Some viruses move from cell to cell by interacting with cellular mechanisms that control the size exclusion limit of PD whereas other viruses alter the PD architecture through assembly of specialized transport structures within the channel. Some viruses move between cells in the form of assembled virus particles whereas other viruses may interact with nucleic acid transport mechanisms to move their genomes in a non-encapsidated form. Moreover, whereas several viruses rely on the secretory pathway to target PD, other viruses interact with the cortical endoplasmic reticulum and associated cytoskeleton to spread infection. This chapter provides an introduction into viruses and their role in studying the diverse cellular mechanisms involved in intercellular PD-mediated macromolecular trafficking.
Collapse
Affiliation(s)
- Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes (IBMP), Centre National de la Recherche Scientifique (CNRS), 12 rue du Général Zimmer, 67084, Strasbourg, France,
| |
Collapse
|
30
|
Kumar D, Kumar R, Hyun TK, Kim JY. Cell-to-cell movement of viruses via plasmodesmata. JOURNAL OF PLANT RESEARCH 2015; 128:37-47. [PMID: 25527904 DOI: 10.1007/s10265-014-0683-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/14/2014] [Indexed: 05/03/2023]
Abstract
Plant viruses utilize plasmodesmata (PD), unique membrane-lined cytoplasmic nanobridges in plants, to spread infection cell-to-cell and long-distance. Such invasion involves a range of regulatory mechanisms to target and modify PD. Exciting discoveries in this field suggest that these mechanisms are executed by the interaction between plant cellular components and viral movement proteins (MPs) or other virus-encoded factors. Striking working analogies exist among endogenous non-cell-autonomous proteins and viral MPs, in which not only do they all use PD to traffic, but also they exploit same regulatory components to exert their functions. Thus, this review discusses on the viral strategies to move via PD and the PD-regulatory mechanisms involved in viral pathogenesis.
Collapse
Affiliation(s)
- Dhinesh Kumar
- Division of Applied Life Science (BK21plus), Department of Biochemistry, Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 27-306, 501 Jinju-Daero, Jinju, 660-701, Korea
| | | | | | | |
Collapse
|
31
|
Peña E, Heinlein M, Sambade A. In vivo RNA labeling using MS2. Methods Mol Biol 2015; 1217:329-41. [PMID: 25287213 DOI: 10.1007/978-1-4939-1523-1_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
The trafficking and asymmetric distribution of cytoplasmic RNA is a fundamental process during development and signaling across phyla. Plants support the intercellular trafficking of RNA molecules such as gene transcripts, small RNAs, and viral RNA genomes by targeting these RNA molecules to plasmodesmata (PD). Intercellular transport of RNA molecules through PD has fundamental implications in the cell-to-cell and systemic signaling during plant development and in the systemic spread of viral disease. Recent advances in time-lapse microscopy allow researchers to approach dynamic biological processes at the molecular level in living cells and tissues. These advances include the ability to label RNA molecules in vivo and thus to monitor their distribution and trafficking. In a broadly used RNA labeling approach, the MS2 method, the RNA of interest is tagged with a specific stem-loop (SL) RNA sequence derived from the origin of assembly region of the bacteriophage MS2 genome that binds to the bacteriophage coat protein (CP) and which, if fused to a fluorescent protein, allows the visualization of the tagged RNA by fluorescence microscopy. Here we describe a protocol for the in vivo visualization of transiently expressed SL-tagged RNA and discuss key aspects to study RNA localization and trafficking to and through plasmodesmata in Nicotiana benthamiana plants.
Collapse
Affiliation(s)
- Eduardo Peña
- Institut de Biologie Moléculaire des Plantes (IBMP), Centre National de la Recherche Scientifique (CNRS), 12 rue du Général Zimmer, 67084, Strasbourg, France
| | | | | |
Collapse
|
32
|
Sager R, Lee JY. Plasmodesmata in integrated cell signalling: insights from development and environmental signals and stresses. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:6337-58. [PMID: 25262225 PMCID: PMC4303807 DOI: 10.1093/jxb/eru365] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
To survive as sedentary organisms built of immobile cells, plants require an effective intercellular communication system, both locally between neighbouring cells within each tissue and systemically across distantly located organs. Such a system enables cells to coordinate their intracellular activities and produce concerted responses to internal and external stimuli. Plasmodesmata, membrane-lined intercellular channels, are essential for direct cell-to-cell communication involving exchange of diffusible factors, including signalling and information molecules. Recent advances corroborate that plasmodesmata are not passive but rather highly dynamic channels, in that their density in the cell walls and gating activities are tightly linked to developmental and physiological processes. Moreover, it is becoming clear that specific hormonal signalling pathways play crucial roles in relaying primary cellular signals to plasmodesmata. In this review, we examine a number of studies in which plasmodesmal structure, occurrence, and/or permeability responses are found to be altered upon given cellular or environmental signals, and discuss common themes illustrating how plasmodesmal regulation is integrated into specific cellular signalling pathways.
Collapse
Affiliation(s)
- Ross Sager
- Department of Plant and Soil Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA
| | - Jung-Youn Lee
- Department of Plant and Soil Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA
| |
Collapse
|
33
|
Peña EJ, Ferriol I, Sambade A, Buschmann H, Niehl A, Elena SF, Rubio L, Heinlein M. Experimental virus evolution reveals a role of plant microtubule dynamics and TORTIFOLIA1/SPIRAL2 in RNA trafficking. PLoS One 2014; 9:e105364. [PMID: 25133612 PMCID: PMC4136834 DOI: 10.1371/journal.pone.0105364] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 07/17/2014] [Indexed: 01/12/2023] Open
Abstract
The cytoskeleton is a dynamic network composed of filamentous polymers and regulatory proteins that provide a flexible structural scaffold to the cell and plays a fundamental role in developmental processes. Mutations that alter the spatial orientation of the cortical microtubule (MT) array of plants are known to cause important changes in the pattern of cell wall synthesis and developmental phenotypes; however, the consequences of such alterations on other MT-network-associated functions in the cytoplasm are not known. In vivo observations suggested a role of cortical MTs in the formation and movement of Tobacco mosaic virus (TMV) RNA complexes along the endoplasmic reticulum (ER). Thus, to probe the significance of dynamic MT behavior in the coordination of MT-network-associated functions related to TMV infection and, thus, in the formation and transport of RNA complexes in the cytoplasm, we performed an evolution experiment with TMV in Arabidopsis thaliana tor1/spr2 and tor2 mutants with specific defects in MT dynamics and asked whether TMV is sensitive to these changes. We show that the altered cytoskeleton induced genetic changes in TMV that were correlated with efficient spread of infection in the mutant hosts. These observations demonstrate a role of dynamic MT rearrangements and of the MT-associated protein TORTIFOLIA1/SPIRAL2 in cellular functions related to virus spread and indicate that MT dynamics and MT-associated proteins represent constraints for virus evolution and adaptation. The results highlight the importance of the dynamic plasticity of the MT network in directing cytoplasmic functions in macromolecular assembly and trafficking and illustrate the value of experimental virus evolution for addressing the cellular functions of dynamic, long-range order systems in multicellular organisms.
Collapse
Affiliation(s)
- Eduardo José Peña
- Institut de Biologie Moléculaire des Plantes, UPR2357 CNRS, Strasbourg, France
| | - Inmaculada Ferriol
- Instituto Valenciano de Investigaciones Agrarias, Moncada, Valencia, Spain
| | - Adrián Sambade
- Department of Comparative Neurobiology, Institut Cavanilles de Biodiversitat i Biologia Evolutiva CIBERNED, Universidad de Valencia, Valencia, Spain
| | - Henrik Buschmann
- Institute for Botany, University of Osnabrück, Osnabrück, Germany
| | - Annette Niehl
- Department of Environmental Sciences, Plant Physiology, University of Basel, Basel, Switzerland
| | - Santiago F. Elena
- Instituto de Biología Molecular y Celular de Plantas, CSIC-UPV, Valencia, Spain
- The Santa Fe Institute, Santa Fe, New Mexico, United States of America
| | - Luis Rubio
- Instituto Valenciano de Investigaciones Agrarias, Moncada, Valencia, Spain
- * E-mail: (LR); (MH)
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes, UPR2357 CNRS, Strasbourg, France
- Department of Environmental Sciences, Plant Physiology, University of Basel, Basel, Switzerland
- * E-mail: (LR); (MH)
| |
Collapse
|
34
|
Niehl A, Pasquier A, Ferriol I, Mély Y, Heinlein M. Comparison of the Oilseed rape mosaic virus and Tobacco mosaic virus movement proteins (MP) reveals common and dissimilar MP functions for tobamovirus spread. Virology 2014; 456-457:43-54. [PMID: 24889224 DOI: 10.1016/j.virol.2014.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/29/2014] [Accepted: 03/09/2014] [Indexed: 11/19/2022]
Abstract
Tobacco mosaic virus (TMV) is a longstanding model for studying virus movement and macromolecular transport through plasmodesmata (PD). Its movement protein (MP) interacts with cortical microtubule (MT)-associated ER sites (C-MERs) to facilitate the formation and transport of ER-associated viral replication complexes (VRCs) along the ER-actin network towards PD. To investigate whether this movement mechanism might be conserved between tobamoviruses, we compared the functions of Oilseed rape mosaic virus (ORMV) MP with those of MP(TMV). We show that MP(ORMV) supports TMV movement more efficiently than MP(TMV). Moreover, MP(ORMV) localizes to C-MERs like MP(TMV) but accumulates to lower levels and does not localize to larger inclusions/VRCs or along MTs, patterns regularly seen for MP(TMV). Our findings extend the role of C-MERs in viral cell-to-cell transport to a virus commonly used for functional genomics in Arabidopsis. Moreover, accumulation of tobamoviral MP in inclusions or along MTs is not required for virus movement.
Collapse
Affiliation(s)
- Annette Niehl
- Institut de Biologie Moléculaire des Plantes du CNRS (UPR 2357), Université de Strasbourg, 12 rue du Général Zimmer, 67000 Strasbourg, France; Zürich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056 Basel, Switzerland.
| | - Adrien Pasquier
- Institut de Biologie Moléculaire des Plantes du CNRS (UPR 2357), Université de Strasbourg, 12 rue du Général Zimmer, 67000 Strasbourg, France
| | - Inmaculada Ferriol
- Instituto Valenciano de Investigaciones Agrarias, 46113 Moncada, Valencia, Spain
| | - Yves Mély
- Laboratoire de Biophotonique et Pharmacologie, CNRS (UMR 7213), Université de Strasbourg, Faculté de Pharmacie, 74 route du Rhin, 67401 Illkirch, France
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes du CNRS (UPR 2357), Université de Strasbourg, 12 rue du Général Zimmer, 67000 Strasbourg, France; Zürich-Basel Plant Science Center, Department of Environmental Sciences, Botany, University of Basel, Hebelstrasse 1, 4056 Basel, Switzerland.
| |
Collapse
|
35
|
The Tobacco mosaic virus movement protein associates with but does not integrate into biological membranes. J Virol 2013; 88:3016-26. [PMID: 24371064 DOI: 10.1128/jvi.03648-13] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
UNLABELLED Plant positive-strand RNA viruses require association with plant cell endomembranes for viral translation and replication, as well as for intra- and intercellular movement of the viral progeny. The membrane association and RNA binding of the Tobacco mosaic virus (TMV) movement protein (MP) are vital for orchestrating the macromolecular network required for virus movement. A previously proposed topological model suggests that TMV MP is an integral membrane protein with two putative α-helical transmembrane (TM) segments. Here we tested this model using an experimental system that measured the efficiency with which natural polypeptide segments were inserted into the ER membrane under conditions approximating the in vivo situation, as well as in planta. Our results demonstrated that the two hydrophobic regions (HRs) of TMV MP do not span biological membranes. We further found that mutations to alter the hydrophobicity of the first HR modified membrane association and precluded virus movement. We propose a topological model in which the TMV MP HRs intimately associate with the cellular membranes, allowing maximum exposure of the hydrophilic domains of the MP to the cytoplasmic cellular components. IMPORTANCE To facilitate plant viral infection and spread, viruses encode one or more movement proteins (MPs) that interact with ER membranes. The present work investigated the membrane association of the 30K MP of Tobacco mosaic virus (TMV), and the results challenge the previous topological model, which predicted that the TMV MP behaves as an integral membrane protein. The current data provide greatly needed clarification of the topological model and provide substantial evidence that TMV MP is membrane associated only at the cytoplasmic face of the membrane and that neither of its domains is integrated into the membrane or translocated into the lumen. Understanding the topology of MPs in the ER is vital for understanding the role of the ER in plant virus transport and for predicting interactions with host factors that mediate resistance to plant viruses.
Collapse
|
36
|
Peña EJ, Heinlein M. Cortical microtubule-associated ER sites: organization centers of cell polarity and communication. CURRENT OPINION IN PLANT BIOLOGY 2013; 16:764-73. [PMID: 24269577 DOI: 10.1016/j.pbi.2013.10.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 09/24/2013] [Accepted: 10/01/2013] [Indexed: 05/21/2023]
Abstract
Anisotropic cell growth and the ability of plant cells to communicate within and across the borders of cellular and supracellular domains depends on the ability of the cells to dynamically establish polarized networks able to deliver structural and informational macromolecules to distinct cellular sites. Studies of organelle movements and transport of endogenous and viral proteins suggest that organelle and macromolecular trafficking pathways involve transient or stable interactions with cortical microtubule-associated endoplasmic reticulum sites (C-MERs). The observations suggest that C-MERs may function as cortical hubs that organize cargo exchange between organelles and allow the recruitment, assembly, and subsequently site-specific delivery of macromolecular complexes. We propose that viruses interact with such hubs for replication and intercellular spread.
Collapse
Affiliation(s)
- Eduardo José Peña
- Institut de Biologie Moléculaire des Plantes, UPR 2357, Centre National de la Recherche Scientifique, Strasbourg 67084, France
| | | |
Collapse
|
37
|
Zavaliev R, Levy A, Gera A, Epel BL. Subcellular dynamics and role of Arabidopsis β-1,3-glucanases in cell-to-cell movement of tobamoviruses. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:1016-30. [PMID: 23656331 DOI: 10.1094/mpmi-03-13-0062-r] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
β-1,3-Glucanases (BG) have been implicated in enhancing virus spread by degrading callose at plasmodesmata (Pd). Here, we investigate the role of Arabidopsis BG in tobamovirus spread. During Turnip vein clearing virus infection, the transcription of two pathogenesis-related (PR)-BG AtBG2 and AtBG3 increased but that of Pd-associated BG AtBG_pap did not change. In transgenic plants, AtBG2 was retained in the endoplasmic reticulum (ER) network and was not secreted. As a stress response mediated by salicylic acid, AtBG2 was secreted and appeared as a free extracellular protein localized in the entire apoplast but did not accumulate at Pd sites. At the leading edge of Tobacco mosaic virus spread, AtBG2 co-localized with the viral movement protein in the ER-derived bodies, similarly to other ER proteins, but was not secreted to the cell wall. In atbg2 mutants, callose levels at Pd and virus spread were unaffected. Likewise, AtBG2 overexpression had no effect on virus spread. However, in atbg_pap mutants, callose at Pd was increased and virus spread was reduced. Our results demonstrate that the constitutive Pd-associated BG but not the stress-regulated extracellular PR-BG are directly involved in regulation of callose at Pd and cell-to-cell transport in Arabidopsis, including the spread of viruses.
Collapse
Affiliation(s)
- Raul Zavaliev
- Department of Molecular Biology and Ecology of Plants, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | | | | | | |
Collapse
|
38
|
Robles Luna G, Peña EJ, Borniego MB, Heinlein M, Garcia ML. Ophioviruses CPsV and MiLBVV movement protein is encoded in RNA 2 and interacts with the coat protein. Virology 2013; 441:152-61. [PMID: 23602594 DOI: 10.1016/j.virol.2013.03.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 03/08/2013] [Accepted: 03/21/2013] [Indexed: 12/15/2022]
Abstract
Citrus psorosis virus (CPsV) and Mirafiori lettuce big-vein virus (MiLBVV), members of the Ophioviridae family, have segmented negative-sense single-stranded RNA genomes. To date no reports have described how ophioviruses spread within host plants and/or the proteins involved in this process. Here we show that the 54K protein of CPsV is encoded by RNA 2 and describe its subcellular distribution. Upon transient expression in Nicotiana benthamiana epidermal cells the 54K protein, and also its 54K counterpart protein of MiLBVV, localize to plasmodesmata and enhance GFP cell-to-cell diffusion between cells. Both proteins, but not the coat proteins (CP) of the respective viruses, functionally trans-complement cell-to-cell movement-defective Potato virus X (PVX) and Tobacco mosaic virus (TMV) mutants. The 54K and 54K proteins interact with the virus-specific CP in the cytoplasm, suggesting a potential role of CP in ophiovirus movement. This is the first study characterizing the movement proteins (MP) of ophioviruses.
Collapse
Affiliation(s)
- Gabriel Robles Luna
- Instituto de Biotecnología y Biología Molecular, CCT-La Plata CONICET, Fac. Cs. Exactas, U.N.L.P., Calles 49 y 115, La Plata, Argentina
| | | | | | | | | |
Collapse
|
39
|
Niehl A, Peña EJ, Amari K, Heinlein M. Microtubules in viral replication and transport. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 75:290-308. [PMID: 23379770 DOI: 10.1111/tpj.12134] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/29/2013] [Accepted: 01/31/2013] [Indexed: 05/05/2023]
Abstract
Viruses use and subvert host cell mechanisms to support their replication and spread between cells, tissues and organisms. Microtubules and associated motor proteins play important roles in these processes in animal systems, and may also play a role in plants. Although transport processes in plants are mostly actin based, studies, in particular with Tobacco mosaic virus (TMV) and its movement protein (MP), indicate direct or indirect roles of microtubules in the cell-to-cell spread of infection. Detailed observations suggest that microtubules participate in the cortical anchorage of viral replication complexes, in guiding their trafficking along the endoplasmic reticulum (ER)/actin network, and also in developing the complexes into virus factories. Microtubules also play a role in the plant-to-plant transmission of Cauliflower mosaic virus (CaMV) by assisting in the development of specific virus-induced inclusions that facilitate viral uptake by aphids. The involvement of microtubules in the formation of virus factories and of other virus-induced inclusions suggests the existence of aggresomal pathways by which plant cells recruit membranes and proteins into localized macromolecular assemblies. Although studies related to the involvement of microtubules in the interaction of viruses with plants focus on specific virus models, a number of observations with other virus species suggest that microtubules may have a widespread role in viral pathogenesis.
Collapse
Affiliation(s)
- Annette Niehl
- Zürich-Basel Plant Science Center, Botany, Department of Environmental Sciences, University of Basel, Hebelstrasse 1, CH-4056 Basel, Switzerland
| | | | | | | |
Collapse
|
40
|
Wu S, Gallagher KL. Intact microtubules are required for the intercellular movement of the SHORT-ROOT transcription factor. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:148-159. [PMID: 23294290 DOI: 10.1111/tpj.12112] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/11/2012] [Accepted: 01/02/2013] [Indexed: 05/28/2023]
Abstract
In both plants and animals, cell-to-cell signaling controls key aspects of development. In plants, cells communicate through direct transfer of transcription factors between cells. It is thought that most, if not all, mobile transcription factors move via plasmodesmata, membrane-lined channels that connect nearly all cells in the plant. However, the mechanisms by which these proteins access the plasmodesmata are not known. Using four independent assays, we examined the movement of the SHORT-ROOT (SHR) transcription factor under conditions that affect microtubule stability, organization or dynamics. We found that intact microtubules are required for cell-to-cell trafficking of SHR. Either chemical or genetic disruption of microtubules results in a significant reduction in SHR transport. Interestingly, inhibition of microtubules also results in mis-localization of the SHR-INTERACTING EMBRYONIC LETHAL (SIEL) protein, which has been shown to bind directly to SHR and is required for SHR movement. These results show that microtubules facilitate cell-to-cell transport of an endogenous plant protein.
Collapse
Affiliation(s)
- Shuang Wu
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | | |
Collapse
|
41
|
Zalepa-King L, Citovsky V. A plasmodesmal glycosyltransferase-like protein. PLoS One 2013; 8:e58025. [PMID: 23469135 PMCID: PMC3582556 DOI: 10.1371/journal.pone.0058025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 01/29/2013] [Indexed: 01/04/2023] Open
Abstract
Plasmodesmata (Pd) are plant intercellular connections that represent cytoplasmic conduits for a wide spectrum of cellular transport cargoes, from ions to house-keeping proteins to transcription factors and RNA silencing signals; furthermore, Pd are also utilized by most plant viruses for their spread between host cells. Despite this central role of Pd in the plant life cycle, their structural and functional composition remains poorly characterized. In this study, we used a known Pd-associated calreticulin protein AtCRT1 as bait to isolate other Pd associated proteins in Arabidopsis thaliana. These experiments identified a beta-1,6-N-acetylglucosaminyl transferase-like enzyme (AtGnTL). Subcellular localization studies using confocal microscopy observed AtGnTL at Pd within living plant cells and demonstrated colocalization with a Pd callose-binding protein (AtPDCB1). That AtGnTL is resident in Pd was consistent with its localization within the plant cell wall following plasmolysis. Initial characterization of an Arabidopsis T-DNA insertional mutant in the AtGnTL gene revealed defects in seed germination and delayed plant growth.
Collapse
Affiliation(s)
- Lisa Zalepa-King
- Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, New York, United States of America
| | - Vitaly Citovsky
- Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, New York, United States of America
- * E-mail:
| |
Collapse
|
42
|
Niehl A, Amari K, Heinlein M. CDC48 function during TMV infection: regulation of virus movement and replication by degradation? PLANT SIGNALING & BEHAVIOR 2013; 8:e22865. [PMID: 23154510 PMCID: PMC3656987 DOI: 10.4161/psb.22865] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Accepted: 11/12/2012] [Indexed: 05/21/2023]
Abstract
Cell-division-cycle protein 48 (CDC48) is an essential, conserved ATP-driven chaperone in eukaryotic cells, which functions in diverse cellular processes including the targeting of misfolded and aggregated proteins for degradation via proteasomal and aggresomal-autophagic pathways. We recently demonstrated that plant CDC48 localizes to and interacts with Tobacco mosaic virus (TMV) movement protein (MP) in ER-associated viral protein inclusions. Our data suggest that CDC48 participates in the clearance of these viral protein inclusions in an ER-assisted protein degradation (ERAD)-like mechanism. As TMV MP-inclusions formed at late infection stages resemble aggresomes, we here propose that TMV MP enters both, ERAD-like and aggresomal pathways in its host cells and that CDC48 coordinates these processes. Moreover, as viruses often exploit host pathways for replication and spread, we propose a model in which CDC48 functions in the degradation pathway of overaccumulating viral protein and also actively participates in the regulation of TMV replication and cell-to-cell movement.
Collapse
Affiliation(s)
- Annette Niehl
- Botany; Department of Environmental Sciences; University of Basel; Basel, Switzerland
- Correspondence to: Annette Niehl,
| | - Khalid Amari
- Botany; Department of Environmental Sciences; University of Basel; Basel, Switzerland
| | - Manfred Heinlein
- Botany; Department of Environmental Sciences; University of Basel; Basel, Switzerland
- Institut de Biologie Moléculaire des Plantes; UPR 2357 CNRS; Université de Strasbourg; Strasbourg, France
| |
Collapse
|
43
|
|
44
|
Peña EJ, Heinlein M. RNA transport during TMV cell-to-cell movement. FRONTIERS IN PLANT SCIENCE 2012; 3:193. [PMID: 22973280 PMCID: PMC3428586 DOI: 10.3389/fpls.2012.00193] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 08/06/2012] [Indexed: 05/08/2023]
Abstract
Studies during the last 25 years have provided increasing evidence for the ability of plants to support the cell-to-cell and systemic transport of RNA molecules and that this process plays a role in plant development and in the systemic orchestration of cellular responses against pathogens and other environmental challenges. Since RNA viruses exploit the cellular RNA transport machineries for spreading their genomes between cells they represent convenient models to investigate the underlying mechanisms. In this regard, the intercellular spread of Tobacco mosaic virus (TMV) has been studied for many years. The RNA of TMV moves cell-to-cell in a non-encapsidated form in a process depending on virus-encoded movement protein (MP). Here, we discuss the current state of the art in studies using TMV and its MP as a model for RNA transport. While the ability of plants to transport viral and cellular RNA molecules is consistent with RNA transport phenomena in other systems, further studies are needed to increase our ability to visualize viral RNA (vRNA) in vivo and to distinguish RNA-transport related processes from those involved in antiviral defense.
Collapse
Affiliation(s)
- Eduardo J. Peña
- Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, Université de StrasbourgStrasbourg, France
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, Université de StrasbourgStrasbourg, France
- Department of Plant Physiology, University of BaselBasel, Switzerland
- *Correspondence: Manfred Heinlein, Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, UPR 2357, Université de Strasbourg, 12, Rue du Général Zimmer, 67084 Strasbourg cedex, France. e-mail:
| |
Collapse
|
45
|
Wu CH, Lee SC, Wang CW. Viral protein targeting to the cortical endoplasmic reticulum is required for cell-cell spreading in plants. ACTA ACUST UNITED AC 2011; 193:521-35. [PMID: 21518793 PMCID: PMC3087015 DOI: 10.1083/jcb.201006023] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Sorting signal-mediated oligomerization and localization of the viral protein TGBp3 to curved ER tubules is essential for viral movement between cells in plants. Many plant RNA viruses use their nonstructural proteins to target and move through the cortical endoplasmic reticulum (ER) tubules within the plant intercellular junction for cell-to-cell spreading. Most of these proteins, including the triple-gene-block 3 protein (TGBp3) of Potexvirus, are ER membrane proteins. We previously showed that TGBp3 of the Bamboo mosaic potexvirus partitions into tubular subdomains of the ER in both yeast and plants, but the mechanism and physiological significance of this localization is unclear. Here, we demonstrate that a sorting signal present in TGBp3 is necessary and sufficient for its oligomerization and for targeting integral membrane proteins into puncta within curved ER tubules. Mutations in the TGBp3 sorting signal impair viral spread, and plants infected with viruses harboring these mutants were either asymptomatic or had reduced symptoms. Thus, we propose that Potexvirus use the sorting signal in TGBp3 to target infectious viral derivatives to cortical ER tubules for transmission through the intercellular junctions in plants.
Collapse
Affiliation(s)
- Chih-Hang Wu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | | | | |
Collapse
|
46
|
Haney MJ, Zhao Y, Li S, Higginbotham SM, Booth SL, Han HY, Vetro JA, Mosley RL, Kabanov AV, Gendelman HE, Batrakova EV. Cell-mediated transfer of catalase nanoparticles from macrophages to brain endothelial, glial and neuronal cells. Nanomedicine (Lond) 2011; 6:1215-30. [PMID: 21449849 DOI: 10.2217/nnm.11.32] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Our laboratories forged the concept of macrophage delivery of protein antioxidants to attenuate neuroinflammation and nigrostriatal neurodegeneration in Parkinson's disease. Notably, the delivery of the redox enzyme, catalase, incorporated into a polyion complex micelle ('nanozyme') by bone marrow-derived macrophages protected nigrostriatum against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intoxication. Nonetheless, how macrophage delivery of nanozyme increases the efficacy of catalase remains unknown. METHODS In this study, we examined the transfer of nanozyme from macrophages to brain microvessel endothelial cells, neurons and astrocytes. RESULTS Facilitated transport of the nanozyme from macrophages to endothelial, neuronal and glial target cells occurred through endocytosis-independent mechanisms that involved fusion of cellular membranes, macrophage bridging conduits and nanozyme lipid coatings. Nanozyme transfer was operative across an artificial blood-brain barrier and showed efficient reactive oxygen species decomposition. CONCLUSION This is the first demonstration, to our knowledge, that drug-loaded macrophages discharge particles to contiguous target cells for therapeutic brain enzyme delivery. The data shown are of potential value for the treatment of neurodegenerative disorders and notably, Parkinson's disease.
Collapse
Affiliation(s)
- Matthew J Haney
- Center for Drug Delivery & Nanomedicine, University of Nebraska, Omaha, NE, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Shemyakina EA, Solovyev AG, Leonova OG, Popenko VI, Schiemann J, Morozov SY. The Role of Microtubule Association in Plasmodesmal Targeting of Potato mop-top virus Movement Protein TGBp1. Open Virol J 2011; 5:1-11. [PMID: 21660184 PMCID: PMC3109696 DOI: 10.2174/1874357901105010001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 10/11/2010] [Accepted: 10/25/2010] [Indexed: 12/19/2022] Open
Abstract
Cell-to-cell movement of Potato mop-top virus (PMTV) is mediated by three virus-encoded ‘triple gene block’ (TGB) proteins termed TGBp1, TGBp2 and TGBp3. TGBp1 binds virus RNAs to form viral ribonucleoprotein complexes (vRNPs), the transport form of viral genome. TGBp2 and TGBp3 are necessary for intracellular delivery of TGBp1-containing vRNPs to plasmodesmata. To analyze subcellular localization and transport of TGBp1 we used a single binary vector for agrobacterium-mediated co-expression of PMTV TGBp1 fused to green fluorescent protein and TGBp2/TGBp3. At two days post infiltration (dpi) TGBp1 was found in the nucleus and in association with microtubules (MTs). Similar localization pattern was revealed in cells expressing GFP-TGBp1 alone after particle bombardment. At 3 dpi, in addition to the nucleus and MTs, TGBp1 was detected in numerous granular bodies located both along the MTs and at the cell wall. The latter structures co-localized with plasmodesmata-associated callose depositions. At 4 dpi, GFP-TGBp1 was detected in cell wall-associated bodies and also in residual MTs, the nucleoplasm and large perinuclear inclusions resembling aggresomes. Therefore GFP-TGBp1 association with MTs preceded to its localization to plasmodesmata. Disassembly of cell MTs by colchicine prevented GFP-TGBp1 targeting to plasmodesmata and the MT-dependent aggresome formation. Deletion analysis also revealed a correlation between TGBp1 microtubule association and plasmodesmata targeting. We propose that TGBp1 interaction with MTs may be important for the formation of vRNP bodies destined for the transport to plasmodesmata as well as degradation of the excessive TGBp1.
Collapse
Affiliation(s)
- Elena A Shemyakina
- Department of Virology, Biological Faculty, Moscow State University, Moscow, 119992, Russia
| | | | | | | | | | | |
Collapse
|
48
|
Hyun TK, Uddin MN, Rim Y, Kim JY. Cell-to-cell trafficking of RNA and RNA silencing through plasmodesmata. PROTOPLASMA 2011; 248:101-16. [PMID: 21042816 DOI: 10.1007/s00709-010-0225-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Accepted: 10/14/2010] [Indexed: 05/05/2023]
Abstract
Plasmodesmata (PD) are plasma membrane-lined cytoplasmic channels that cross the cell wall and establish symplasmic continuity between neighboring cells in plants. Recently, a wide range of cellular RNAs (including mRNAs and small RNAs (sRNAs)) have been reported to move from cell to cell through PD trafficking pathways. sRNAs are key molecules that function in transcriptional and post-transcriptional RNA silencing, which is a gene expression regulatory mechanism that is conserved among eukaryotes and is important for protection against invading nucleic acids (such as viruses and transposons) and for developmental and physiological regulation. One of the most intriguing aspects of RNA silencing is that it can function either cell autonomously or non-cell autonomously in post-transcriptional RNA silencing pathways. Although the mechanisms underlying cell-to-cell trafficking of RNA and RNA silencing signals are not fully understood, the movement of specific RNAs seems to play a critical role in cell-to-cell and long-distance regulation of gene expression, thereby coordinating growth and developmental processes, gene silencing, and stress responses. In this review, we summarize the current knowledge regarding cell-to-cell trafficking of RNA molecules (including small RNAs), and we discuss potential molecular mechanisms of cell-to-cell trafficking that are mediated by complex networks.
Collapse
Affiliation(s)
- Tae Kyung Hyun
- Department of Biochemistry, Division of Applied Life Science (BK21 program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, 660-701, South Korea
| | | | | | | |
Collapse
|
49
|
Niehl A, Heinlein M. Cellular pathways for viral transport through plasmodesmata. PROTOPLASMA 2011; 248:75-99. [PMID: 21125301 DOI: 10.1007/s00709-010-0246-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Accepted: 11/16/2010] [Indexed: 05/03/2023]
Abstract
Plant viruses use plasmodesmata (PD) to spread infection between cells and systemically. Dependent on viral species, movement through PD can occur in virion or non-virion form, and requires different mechanisms for targeting and modification of the pore. These mechanisms are supported by viral movement proteins and by other virus-encoded factors that interact among themselves and with plant cellular components to facilitate virus movement in a coordinated and regulated fashion.
Collapse
Affiliation(s)
- Annette Niehl
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, 12 rue du Général Zimmer, 67084, Strasbourg, France
| | | |
Collapse
|
50
|
Amari K, Boutant E, Hofmann C, Schmitt-Keichinger C, Fernandez-Calvino L, Didier P, Lerich A, Mutterer J, Thomas CL, Heinlein M, Mély Y, Maule AJ, Ritzenthaler C. A family of plasmodesmal proteins with receptor-like properties for plant viral movement proteins. PLoS Pathog 2010; 6:e1001119. [PMID: 20886105 PMCID: PMC2944810 DOI: 10.1371/journal.ppat.1001119] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Accepted: 08/24/2010] [Indexed: 01/10/2023] Open
Abstract
Plasmodesmata (PD) are essential but poorly understood structures in plant cell walls that provide symplastic continuity and intercellular communication pathways between adjacent cells and thus play fundamental roles in development and pathogenesis. Viruses encode movement proteins (MPs) that modify these tightly regulated pores to facilitate their spread from cell to cell. The most striking of these modifications is observed for groups of viruses whose MPs form tubules that assemble in PDs and through which virions are transported to neighbouring cells. The nature of the molecular interactions between viral MPs and PD components and their role in viral movement has remained essentially unknown. Here, we show that the family of PD-located proteins (PDLPs) promotes the movement of viruses that use tubule-guided movement by interacting redundantly with tubule-forming MPs within PDs. Genetic disruption of this interaction leads to reduced tubule formation, delayed infection and attenuated symptoms. Our results implicate PDLPs as PD proteins with receptor-like properties involved the assembly of viral MPs into tubules to promote viral movement.
Collapse
Affiliation(s)
- Khalid Amari
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Emmanuel Boutant
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Christina Hofmann
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | | | - Lourdes Fernandez-Calvino
- Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Pascal Didier
- UMR 7213 CNRS, Biophotonique et Pharmacologie/Université de Strasbourg, Faculté de Pharmacie, Illkirch, France
| | - Alexander Lerich
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Jérome Mutterer
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Carole L. Thomas
- Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Manfred Heinlein
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Yves Mély
- UMR 7213 CNRS, Biophotonique et Pharmacologie/Université de Strasbourg, Faculté de Pharmacie, Illkirch, France
| | - Andrew J. Maule
- Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Norwich, United Kingdom
| | - Christophe Ritzenthaler
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| |
Collapse
|