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Kumar R, Iswanto ABB, Kumar D, Shuwei W, Oh K, Moon J, Son GH, Oh ES, Vu MH, Lee J, Lee KW, Oh MH, Kwon C, Chung WS, Kim JY, Kim SH. C-Type LECTIN receptor-like kinase 1 and ACTIN DEPOLYMERIZING FACTOR 3 are key components of plasmodesmata callose modulation. PLANT, CELL & ENVIRONMENT 2024. [PMID: 38780063 DOI: 10.1111/pce.14957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 04/02/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024]
Abstract
Plasmodesmata (PDs) are intercellular organelles carrying multiple membranous nanochannels that allow the trafficking of cellular signalling molecules. The channel regulation of PDs occurs dynamically and is required in various developmental and physiological processes. It is well known that callose is a critical component in regulating PD permeability or symplasmic connectivity, but the understanding of the signalling pathways and mechanisms of its regulation is limited. Here, we used the reverse genetic approach to investigate the role of C-type lectin receptor-like kinase 1 (CLRLK1) in the aspect of PD callose-modulated symplasmic continuity. Here, we found that loss-of-function mutations in CLRLK1 resulted in excessive PD callose deposits and reduced symplasmic continuity, resulting in an accelerated gravitropic response. The protein interactome study also found that CLRLK1 interacted with actin depolymerizing factor 3 (ADF3) in vitro and in plants. Moreover, mutations in ADF3 result in elevated PD callose deposits and faster gravitropic response. Our results indicate that CLRLK1 and ADF3 negatively regulate PD callose accumulation, contributing to fine-tuning symplasmic opening apertures. Overall, our studies identified two key components involved in the deposits of PD callose and provided new insights into how symplasmic connectivity is maintained by the control of PD callose homoeostasis.
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Affiliation(s)
- Ritesh Kumar
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Arya B B Iswanto
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Dhinesh Kumar
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Wu Shuwei
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Kyujin Oh
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Jiyun Moon
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Geon H Son
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Eun-Seok Oh
- Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Minh H Vu
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Jinsu Lee
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Keun W Lee
- Division of Life Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Man-Ho Oh
- Department of Biological Sciences, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, Republic of Korea
| | - Chian Kwon
- Department of Molecular Biology, Dankook University, Cheonan, Korea
| | - Woo S Chung
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
- Division of Life Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Jae-Yean Kim
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
- Division of Life Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Sang H Kim
- Division of Applied Life Science (BK21 Four Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
- Division of Life Science, Gyeongsang National University, Jinju, Republic of Korea
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2
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Naveed ZA, Jamil M, Asif N, Waqas M, Ajaz S, Khan SH. Cross-regulation of cytoskeleton and calcium signaling at plant-pathogen interface. Cell Signal 2024; 117:111100. [PMID: 38360248 DOI: 10.1016/j.cellsig.2024.111100] [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] [Received: 10/09/2023] [Revised: 02/06/2024] [Accepted: 02/12/2024] [Indexed: 02/17/2024]
Abstract
During plant-pathogen interactions, cytoskeleton and calcium signaling work independently as well as in coordination with each other for developing preformed and induced defense responses. A cell wall (CW) - plasma membrane (PM) - cytoskeleton (CS) continuum is maintained by coordination of cytoskeleton and calcium signaling. The current review is focused on the current knowledge of cytoskeleton‑calcium cross-regulation during plant-pathogen interactions. Implications of recent technological developments in the existing toolkit that can address the outstanding questions of cytoskeleton‑calcium coordination plant immunity are also discussed.
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Affiliation(s)
- Zunaira Afzal Naveed
- Center for Advanced Studies in Agriculture and Food Security, University of Agriculture Faisalabad, Pakistan; Center of Agricultural Biochemistry and Biotechnology, University of Agriculture Faisalabad, Pakistan
| | - Mahnoor Jamil
- Center for Advanced Studies in Agriculture and Food Security, University of Agriculture Faisalabad, Pakistan
| | - Nouman Asif
- Center for Advanced Studies in Agriculture and Food Security, University of Agriculture Faisalabad, Pakistan
| | - Muhammad Waqas
- Center for Advanced Studies in Agriculture and Food Security, University of Agriculture Faisalabad, Pakistan
| | - Sobia Ajaz
- Center for Advanced Studies in Agriculture and Food Security, University of Agriculture Faisalabad, Pakistan
| | - Sultan Habibullah Khan
- Center for Advanced Studies in Agriculture and Food Security, University of Agriculture Faisalabad, Pakistan; Center of Agricultural Biochemistry and Biotechnology, University of Agriculture Faisalabad, Pakistan.
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3
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Yuan G, Gao H, Yang T. Exploring the Role of the Plant Actin Cytoskeleton: From Signaling to Cellular Functions. Int J Mol Sci 2023; 24:15480. [PMID: 37895158 PMCID: PMC10607326 DOI: 10.3390/ijms242015480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/06/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023] Open
Abstract
The plant actin cytoskeleton is characterized by the basic properties of dynamic array, which plays a central role in numerous conserved processes that are required for diverse cellular functions. Here, we focus on how actins and actin-related proteins (ARPs), which represent two classical branches of a greatly diverse superfamily of ATPases, are involved in fundamental functions underlying signal regulation of plant growth and development. Moreover, we review the structure, assembly dynamics, and biological functions of filamentous actin (F-actin) from a molecular perspective. The various accessory proteins known as actin-binding proteins (ABPs) partner with F-actin to finely tune actin dynamics, often in response to various cell signaling pathways. Our understanding of the significance of the actin cytoskeleton in vital cellular activities has been furthered by comparison of conserved functions of actin filaments across different species combined with advanced microscopic techniques and experimental methods. We discuss the current model of the plant actin cytoskeleton, followed by examples of the signaling mechanisms under the supervision of F-actin related to cell morphogenesis, polar growth, and cytoplasmic streaming. Determination of the theoretical basis of how the cytoskeleton works is important in itself and is beneficial to future applications aimed at improving crop biomass and production efficiency.
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Affiliation(s)
| | | | - Tao Yang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China; (G.Y.); (H.G.)
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Ham BK, Wang X, Toscano-Morales R, Lin J, Lucas WJ. Plasmodesmal endoplasmic reticulum proteins regulate intercellular trafficking of cucumber mosaic virus in Arabidopsis. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:4401-4414. [PMID: 37210666 PMCID: PMC10838158 DOI: 10.1093/jxb/erad190] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 05/17/2023] [Indexed: 05/22/2023]
Abstract
Plasmodesmata (PD) are plasma membrane-lined cytoplasmic nanochannels that mediate cell-to-cell communication across the cell wall. A range of proteins are embedded in the PD plasma membrane and endoplasmic reticulum (ER), and function in regulating PD-mediated symplasmic trafficking. However, knowledge of the nature and function of the ER-embedded proteins in the intercellular movement of non-cell-autonomous proteins is limited. Here, we report the functional characterization of two ER luminal proteins, AtBiP1/2, and two ER integral membrane proteins, AtERdj2A/B, which are located within the PD. These PD proteins were identified as interacting proteins with cucumber mosaic virus (CMV) movement protein (MP) in co-immunoprecipitation studies using an Arabidopsis-derived plasmodesmal-enriched cell wall protein preparation (PECP). The AtBiP1/2 PD location was confirmed by TEM-based immunolocalization, and their AtBiP1/2 signal peptides (SPs) function in PD targeting. In vitro/in vivo pull-down assays revealed the association between AtBiP1/2 and CMV MP, mediated by AtERdj2A, through the formation of an AtBiP1/2-AtERdj2-CMV MP complex within PD. The role of this complex in CMV infection was established, as systemic infection was retarded in bip1/bip2w and erdj2b mutants. Our findings provide a model for a mechanism by which the CMV MP mediates cell-to-cell trafficking of its viral ribonucleoprotein complex.
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Affiliation(s)
- Byung-Kook Ham
- Global Institute for Food Security (GIFS), University of Saskatchewan, 421 Downey Rd, Saskatoon, SK S7N 4L8, Canada
- Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, SK S7N 5E2, Canada
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA
| | - Xiaohua Wang
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Roberto Toscano-Morales
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA
| | - Jinxing Lin
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - William J Lucas
- Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA
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5
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Niñoles R, Arjona P, Azad SM, Hashim A, Casañ J, Bueso E, Serrano R, Espinosa A, Molina I, Gadea J. Kaempferol-3-rhamnoside overaccumulation in flavonoid 3'-hydroxylase tt7 mutants compromises seed coat outer integument differentiation and seed longevity. THE NEW PHYTOLOGIST 2023; 238:1461-1478. [PMID: 36829299 DOI: 10.1111/nph.18836] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Seeds slowly accumulate damage during storage, which ultimately results in germination failure. The seed coat protects the embryo from the external environment, and its composition is critical for seed longevity. Flavonols accumulate in the outer integument. The link between flavonol composition and outer integument development has not been explored. Genetic, molecular and ultrastructural assays on loss-of-function mutants of the flavonoid biosynthesis pathway were used to study the effect of altered flavonoid composition on seed coat development and seed longevity. Controlled deterioration assays indicate that loss of function of the flavonoid 3' hydroxylase gene TT7 dramatically affects seed longevity and seed coat development. Outer integument differentiation is compromised from 9 d after pollination in tt7 developing seeds, resulting in a defective suberin layer and incomplete degradation of seed coat starch. These distinctive phenotypes are not shared by other mutants showing abnormal flavonoid composition. Genetic analysis indicates that overaccumulation of kaempferol-3-rhamnoside is mainly responsible for the observed phenotypes. Expression profiling suggests that multiple cellular processes are altered in the tt7 mutant. Overaccumulation of kaempferol-3-rhamnoside in the seed coat compromises normal seed coat development. This observation positions TRANSPARENT TESTA 7 and the UGT78D1 glycosyltransferase, catalysing flavonol 3-O-rhamnosylation, as essential players in the modulation of seed longevity.
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Affiliation(s)
- Regina Niñoles
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Paloma Arjona
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Sepideh M Azad
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Aseel Hashim
- Department of Biology, Algoma University, 1520 Queen Street East, Sault Ste. Marie, ON, P6A 2G4, Canada
| | - Jose Casañ
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Eduardo Bueso
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Ramón Serrano
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Ana Espinosa
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
| | - Isabel Molina
- Department of Biology, Algoma University, 1520 Queen Street East, Sault Ste. Marie, ON, P6A 2G4, Canada
| | - Jose Gadea
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ed. 8E, C/Ingeniero Fausto Elio s/n, 46022, Valencia, Spain
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Wang P, Duckney P, Gao E, Hussey PJ, Kriechbaumer V, Li C, Zang J, Zhang T. Keep in contact: multiple roles of endoplasmic reticulum-membrane contact sites and the organelle interaction network in plants. THE NEW PHYTOLOGIST 2023; 238:482-499. [PMID: 36651025 DOI: 10.1111/nph.18745] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Functional regulation and structural maintenance of the different organelles in plants contribute directly to plant development, reproduction and stress responses. To ensure these activities take place effectively, cells have evolved an interconnected network amongst various subcellular compartments, regulating rapid signal transduction and the exchange of biomaterial. Many proteins that regulate membrane connections have recently been identified in plants, and this is the first step in elucidating both the mechanism and function of these connections. Amongst all organelles, the endoplasmic reticulum is the key structure, which likely links most of the different subcellular compartments through membrane contact sites (MCS) and the ER-PM contact sites (EPCS) have been the most intensely studied in plants. However, the molecular composition and function of plant MCS are being found to be different from other eukaryotic systems. In this article, we will summarise the most recent advances in this field and discuss the mechanism and biological relevance of these essential links in plants.
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Affiliation(s)
- Pengwei Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Patrick Duckney
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Erlin Gao
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Patrick J Hussey
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Verena Kriechbaumer
- Endomembrane Structure and Function Research Group, Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK
| | - Chengyang Li
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Jingze Zang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
| | - Tong Zhang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture & Forestry Sciences, Huazhong Agricultural University, Wuhan, 430070, China
- Hubei Hongshan Laboratory, Wuhan, 430070, China
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7
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Real N, Villar I, Serrano I, Guiu-Aragonés C, Martín-Hernández AM. Mutations in CmVPS41 controlling resistance to cucumber mosaic virus display specific subcellular localization. PLANT PHYSIOLOGY 2023; 191:1596-1611. [PMID: 36527697 PMCID: PMC10022621 DOI: 10.1093/plphys/kiac583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/29/2022] [Indexed: 06/17/2023]
Abstract
Resistance to cucumber mosaic virus (CMV) in melon (Cucumis melo L.) has been described in several exotic accessions and is controlled by a recessive resistance gene, cmv1, that encodes a vacuolar protein sorting 41 (CmVPS41). cmv1 prevents systemic infection by restricting the virus to the bundle sheath cells, preventing viral phloem entry. CmVPS41 from different resistant accessions carries two causal mutations, either a G85E change, found in Pat-81 and Freeman's cucumber, or L348R, found in PI161375, cultivar Songwhan Charmi (SC). Here, we analyzed the subcellular localization of CmVPS41 in Nicotiana benthamiana and found differential structures in resistant and susceptible accessions. Susceptible accessions showed nuclear and membrane spots and many transvacuolar strands, whereas the resistant accessions showed many intravacuolar invaginations. These specific structures colocalized with late endosomes. Artificial CmVPS41 carrying individual mutations causing resistance in the genetic background of CmVPS41 from the susceptible variety Piel de Sapo (PS) revealed that the structure most correlated with resistance was the absence of transvacuolar strands. Coexpression of CmVPS41 with viral movement proteins, the determinant of virulence, did not change these localizations; however, infiltration of CmVPS41 from either SC or PS accessions in CMV-infected N. benthamiana leaves showed a localization pattern closer to each other, with up to 30% cells showing some membrane spots in the CmVPS41SC and fewer transvacuolar strands (reduced from a mean of 4 to 1-2) with CmVPS41PS. Our results suggest that the distribution of CmVPS41PS in late endosomes includes transvacuolar strands that facilitate CMV infection and that CmVPS41 re-localizes during viral infection.
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Affiliation(s)
- Núria Real
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, C/Vall Moronta, Edifici CRAG, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
| | - Irene Villar
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, C/Vall Moronta, Edifici CRAG, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
- Universidad de Zaragoza, Calle Pedro Cerbuna, 12, 50009 Zaragoza, Spain
| | - Irene Serrano
- Laboratoire des Interactions des Plantes et Microorganismes, CNRS, 31326 Toulouse, France
| | - Cèlia Guiu-Aragonés
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, C/Vall Moronta, Edifici CRAG, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
| | - Ana Montserrat Martín-Hernández
- Centre for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, C/Vall Moronta, Edifici CRAG, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
- Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Edifici CRAG, C/ Vall Moronta, Bellaterra (Cerdanyola del Vallés), 08193 Barcelona, Spain
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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.
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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
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9
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Abstract
Our current understanding of plant viruses stems largely from those affecting economically important plants. Yet plant species in cultivation represent a small and biased subset of the plant kingdom. Here, we describe virus diversity and abundance in 1,079 transcriptomes from species across the breadth of the plant kingdom (Archaeplastida) by analyzing open-source data from the 1000 Plant Transcriptomes Initiative (1KP). We identified 104 potentially novel viruses, of which 40% were single-stranded positive-sense RNA viruses across eight orders, including members of the Hepelivirales, Tymovirales, Cryppavirales, Martellivirales, and Picornavirales. One-third of the newly described viruses were double-stranded RNA viruses from the orders Durnavirales and Ghabrivirales. The remaining were negative-sense RNA viruses from the Rhabdoviridae, Aspiviridae, Yueviridae, and Phenuiviridae and the newly proposed Viridisbunyaviridae. Our analysis considerably expands the known host range of 13 virus families to include lower plants (e.g., Benyviridae and Secoviridae) and 4 virus families to include alga hosts (e.g., Tymoviridae and Chrysoviridae). More broadly, however, a cophylogeny analysis revealed that the evolutionary history of these families is largely driven by cross-species transmission events. The discovery of the first 30-kDa movement protein in a nonvascular plant suggests that the acquisition of plant virus movement proteins occurred prior to the emergence of the plant vascular system. Together, these data highlight that numerous RNA virus families are associated with older evolutionary plant lineages than previously thought and that the apparent scarcity of RNA viruses found in lower plants likely reflects a lack of investigation rather than their absence. IMPORTANCE Our knowledge of plant viruses is mainly limited to those infecting economically important host species. In particular, we know little about those viruses infecting basal plant lineages such as the ferns, lycophytes, bryophytes, and charophytes. To expand this understanding, we conducted a broad-scale viral survey of species across the breadth of the plant kingdom. We found that basal plants harbor a wide diversity of RNA viruses, including some that are sufficiently divergent to likely compose a new virus family. The basal plant virome revealed offers key insights into the evolutionary history of core plant virus gene modules and genome segments. More broadly, this work emphasizes that the scarcity of viruses found in these species to date most likely reflects the limited research in this area.
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10
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Yue N, Jiang Z, Zhang X, Li Z, Wang X, Wen Z, Gao Z, Pi Q, Zhang Y, Wang X, Han C, Yu J, Li D. Palmitoylation of γb protein directs a dynamic switch between Barley stripe mosaic virus replication and movement. EMBO J 2022; 41:e110060. [PMID: 35642376 PMCID: PMC9251889 DOI: 10.15252/embj.2021110060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 04/28/2022] [Accepted: 05/05/2022] [Indexed: 11/09/2022] Open
Abstract
Viral replication and movement are intimately linked; however, the molecular mechanisms regulating the transition between replication and subsequent movement remain largely unknown. We previously demonstrated that the Barley stripe mosaic virus (BSMV) γb protein promotes viral replication and movement by interacting with the αa replicase and TGB1 movement proteins. Here, we found that γb is palmitoylated at Cys-10, Cys-19, and Cys-60 in Nicotiana benthamiana, which supports BSMV infection. Intriguingly, non-palmitoylated γb is anchored to chloroplast replication sites and enhances BSMV replication, whereas palmitoylated γb protein recruits TGB1 to the chloroplasts and forms viral replication-movement intermediate complexes. At the late stages of replication, γb interacts with NbPAT15 and NbPAT21 and is palmitoylated at the chloroplast periphery, thereby shifting viral replication to intracellular and intercellular movement. We also show that palmitoylated γb promotes virus cell-to-cell movement by interacting with NbREM1 to inhibit callose deposition at the plasmodesmata. Altogether, our experiments reveal a model whereby palmitoylation of γb directs a dynamic switch between BSMV replication and movement events during infection.
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Affiliation(s)
- Ning Yue
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Zhihao Jiang
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Xuan Zhang
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Zhenggang Li
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Xueting Wang
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Zhiyan Wen
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Zongyu Gao
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Qinglin Pi
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Yongliang Zhang
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Xian‐Bing Wang
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Chenggui Han
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Jialin Yu
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
| | - Dawei Li
- State Key Laboratory of Agro‐Biotechnology, College of Biological SciencesChina Agricultural UniversityBeijingChina
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11
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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.
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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.
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12
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Jiang J, Kuo YW, Salem N, Erickson A, Falk BW. Carrot mottle virus ORF4 movement protein targets plasmodesmata by interacting with the host cell SUMOylation system. THE NEW PHYTOLOGIST 2021; 231:382-398. [PMID: 33774829 DOI: 10.1111/nph.17370] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Indexed: 06/12/2023]
Abstract
Plant virus movement proteins (MPs) facilitate virus spread in their plant hosts, and some of them are known to target plasmodesmata (PD). However, how the MPs target PD is still largely unknown. Carrot mottle virus (CMoV) encodes the ORF3 and ORF4 proteins, which are involved in CMoV movement. In this study, we used CMoV as a model to study the PD targeting of a plant virus MP. We showed that the CMoV ORF4 protein, but not the ORF3 protein, modified PD and led to the virus movement. We found that the CMoV ORF4 protein interacts with the host cell small ubiquitin-like modifier (SUMO) 1, 2 and the SUMO-conjugating enzyme SCE1, resulting in the ORF4 protein SUMOylation. Downregulation of mRNAs for NbSCE1 and NbSUMO impaired CMoV infection. The SUMO-interacting motifs (SIMs) LVIVF, VIWV, and a lysine residue at position 78 (K78) are required for the ORF4 protein SUMOylation. The mutation of these motifs prevented the protein to efficiently target PD, and further slowed or completely abolished CMoV systemic movement. Finally, we found that some of these motifs are highly conserved among umbraviruses. Our data suggest that the CMoV ORF4 protein targets PD by interacting with the host cell SUMOylation system.
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Affiliation(s)
- Jun Jiang
- Department of Plant Pathology, University of California, Davis, CA, 95616, USA
| | - Yen-Wen Kuo
- Department of Plant Pathology, University of California, Davis, CA, 95616, USA
| | - Nidà Salem
- Department of Plant Protection, School of Agriculture, The University of Jordan, Amman, 11942, Jordan
| | - Anna Erickson
- Department of Plant Pathology, University of California, Davis, CA, 95616, USA
| | - Bryce W Falk
- Department of Plant Pathology, University of California, Davis, CA, 95616, USA
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13
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Rahman MS, Madina MH, Plourde MB, dos Santos KCG, Huang X, Zhang Y, Laliberté JF, Germain H. The Fungal Effector Mlp37347 Alters Plasmodesmata Fluxes and Enhances Susceptibility to Pathogen. Microorganisms 2021; 9:microorganisms9061232. [PMID: 34204123 PMCID: PMC8228402 DOI: 10.3390/microorganisms9061232] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 05/28/2021] [Accepted: 06/03/2021] [Indexed: 12/15/2022] Open
Abstract
Melampsora larici-populina (Mlp) is a devastating pathogen of poplar trees, causing the defoliating poplar leaf rust disease. Genomic studies have revealed that Mlp possesses a repertoire of 1184 small secreted proteins (SSPs), some of them being characterized as candidate effectors. However, how they promote virulence is still unclear. This study investigates the candidate effector Mlp37347’s role during infection. We developed a stable Arabidopsis transgenic line expressing Mlp37347 tagged with the green fluorescent protein (GFP). We found that the effector accumulated exclusively at plasmodesmata (PD). Moreover, the presence of the effector at plasmodesmata favors enhanced plasmodesmatal flux and reduced callose deposition. Transcriptome profiling and a gene ontology (GO) analysis of transgenic Arabidopsis plants expressing the effector revealed that the genes involved in glucan catabolic processes are up-regulated. This effector has previously been shown to interact with glutamate decarboxylase 1 (GAD1), and in silico docking analysis supported the strong binding between Mlp37347 and GAD1 in this study. In infection assays, the effector promoted Hyalonoperospora arabidopsidis growth but not bacterial growth. Our investigation suggests that the effector Mlp37347 targets PD in host cells and promotes parasitic growth.
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Affiliation(s)
- Md. Saifur Rahman
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada; (M.S.R.); (M.H.M.); (M.B.P.); (K.C.G.d.S.)
- Department of Computational Medicine and Bioinformatics, University of Michigan, 100 Washtenaw Avenue, Ann Arbor, MI 48109, USA; (X.H.); (Y.Z.)
| | - Mst Hur Madina
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada; (M.S.R.); (M.H.M.); (M.B.P.); (K.C.G.d.S.)
| | - Mélodie B. Plourde
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada; (M.S.R.); (M.H.M.); (M.B.P.); (K.C.G.d.S.)
| | - Karen Cristine Gonçalves dos Santos
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada; (M.S.R.); (M.H.M.); (M.B.P.); (K.C.G.d.S.)
| | - Xiaoqiang Huang
- Department of Computational Medicine and Bioinformatics, University of Michigan, 100 Washtenaw Avenue, Ann Arbor, MI 48109, USA; (X.H.); (Y.Z.)
| | - Yang Zhang
- Department of Computational Medicine and Bioinformatics, University of Michigan, 100 Washtenaw Avenue, Ann Arbor, MI 48109, USA; (X.H.); (Y.Z.)
| | - Jean-François Laliberté
- Institut National de la Recherche Scientifique-Centre Armand-Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada;
| | - Hugo Germain
- Department of Chemistry, Biochemistry and Physics, Université du Québec à Trois-Rivières, Trois-Rivières, QC G8Z 4M3, Canada; (M.S.R.); (M.H.M.); (M.B.P.); (K.C.G.d.S.)
- Correspondence:
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14
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Liu J, Zhang L, Yan D. Plasmodesmata-Involved Battle Against Pathogens and Potential Strategies for Strengthening Hosts. FRONTIERS IN PLANT SCIENCE 2021; 12:644870. [PMID: 34149749 PMCID: PMC8210831 DOI: 10.3389/fpls.2021.644870] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 04/28/2021] [Indexed: 06/01/2023]
Abstract
Plasmodesmata (PD) are membrane-lined pores that connect adjacent cells to mediate symplastic communication in plants. These intercellular channels enable cell-to-cell trafficking of various molecules essential for plant development and stress responses, but they can also be utilized by pathogens to facilitate their infection of hosts. Some pathogens or their effectors are able to spread through the PD by modifying their permeability. Yet plants have developed various corresponding defense mechanisms, including the regulation of PD to impede the spread of invading pathogens. In this review, we aim to illuminate the various roles of PD in the interactions between pathogens and plants during the infection process. We summarize the pathogenic infections involving PD and how the PD could be modified by pathogens or hosts. Furthermore, we propose several hypothesized and promising strategies for enhancing the disease resistance of host plants by the appropriate modulation of callose deposition and plasmodesmal permeability based on current knowledge.
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Affiliation(s)
- Jie Liu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
| | - Lin Zhang
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou, China
| | - Dawei Yan
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, China
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15
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Chen C, Vanneste S, Chen X. Review: Membrane tethers control plasmodesmal function and formation. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 304:110800. [PMID: 33568299 DOI: 10.1016/j.plantsci.2020.110800] [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: 07/29/2020] [Revised: 12/07/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Cell-to-cell communication is crucial in coordinating diverse biological processes in multicellular organisms. In plants, communication between adjacent cells occurs via nanotubular passages called plasmodesmata (PD). The PD passage is composed of an appressed endoplasmic reticulum (ER) internally, and plasma membrane (PM) externally, that traverses the cell wall, and associates with the actin-cytoskeleton. The coordination of the ER, PM and cytoskeleton plays a potential role in maintaining the architecture and conductivity of PD. Many data suggest that PD-associated proteins can serve as tethers that connect these structures in a functional PD, to regulate cell-to-cell communication. In this review, we summarize the organization and regulation of PD activity via tethering proteins, and discuss the importance of PD-mediated cell-to-cell communication in plant development and defense against environmental stress.
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Affiliation(s)
- Chaofan Chen
- College of Life Science and Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, Fuzhou, China; FAFU-UCR Joint Center for Horticultural Biology and Metabolomics, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Steffen Vanneste
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Department of Plants and Crops, Ghent University, Coupure links 653, 9000 Ghent, Belgium; Lab of Plant Growth Analysis, Ghent University Global Campus, Songdomunhwa-Ro, 119, Yeonsu-gu, Incheon 21985, Republic of Korea
| | - Xu Chen
- FAFU-UCR Joint Center for Horticultural Biology and Metabolomics, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, China.
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16
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Diao M, Huang S. An Update on the Role of the Actin Cytoskeleton in Plasmodesmata: A Focus on Formins. FRONTIERS IN PLANT SCIENCE 2021; 12:647123. [PMID: 33659020 PMCID: PMC7917184 DOI: 10.3389/fpls.2021.647123] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 01/26/2021] [Indexed: 06/12/2023]
Abstract
Cell-to-cell communication in plants is mediated by plasmodesmata (PD) whose permeability is tightly regulated during plant growth and development. The actin cytoskeleton has been implicated in regulating the permeability of PD, but the underlying mechanism remains largely unknown. Recent characterization of PD-localized formin proteins has shed light on the role and mechanism of action of actin in regulating PD-mediated intercellular trafficking. In this mini-review article, we will describe the progress in this area.
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Affiliation(s)
- Min Diao
- iHuman Institute, Shanghai Tech University, Shanghai, China
| | - Shanjin Huang
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
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17
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Veerabagu M, Rinne PLH, Skaugen M, Paul LK, van der Schoot C. Lipid Body Dynamics in Shoot Meristems: Production, Enlargement, and Putative Organellar Interactions and Plasmodesmal Targeting. FRONTIERS IN PLANT SCIENCE 2021; 12:674031. [PMID: 34367200 PMCID: PMC8335594 DOI: 10.3389/fpls.2021.674031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 06/14/2021] [Indexed: 05/20/2023]
Abstract
Post-embryonic cells contain minute lipid bodies (LBs) that are transient, mobile, engage in organellar interactions, and target plasmodesmata (PD). While LBs can deliver γ-clade 1,3-β-glucanases to PD, the nature of other cargo is elusive. To gain insight into the poorly understood role of LBs in meristems, we investigated their dynamics by microscopy, gene expression analyzes, and proteomics. In developing buds, meristems accumulated LBs, upregulated several LB-specific OLEOSIN genes and produced OLEOSINs. During bud maturation, the major gene OLE6 was strongly downregulated, OLEOSINs disappeared from bud extracts, whereas lipid biosynthesis genes were upregulated, and LBs were enlarged. Proteomic analyses of the LB fraction of dormant buds confirmed that OLEOSINs were no longer present. Instead, we identified the LB-associated proteins CALEOSIN (CLO1), Oil Body Lipase 1 (OBL1), Lipid Droplet Interacting Protein (LDIP), Lipid Droplet Associated Protein1a/b (LDAP1a/b) and LDAP3a/b, and crucial components of the OLEOSIN-deubiquitinating and degradation machinery, such as PUX10 and CDC48A. All mRFP-tagged LDAPs localized to LBs when transiently expressed in Nicotiana benthamiana. Together with gene expression analyzes, this suggests that during bud maturation, OLEOSINs were replaced by LDIP/LDAPs at enlarging LBs. The LB fraction contained the meristem-related actin7 (ACT7), "myosin XI tail-binding" RAB GTPase C2A, an LB/PD-associated γ-clade 1,3-β-glucanase, and various organelle- and/or PD-localized proteins. The results are congruent with a model in which LBs, motorized by myosin XI-k/1/2, traffic on F-actin, transiently interact with other organelles, and deliver a diverse cargo to PD.
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Affiliation(s)
- Manikandan Veerabagu
- Faculty of Biosciences, Department of Plant Sciences, Norwegian University of Life Sciences, Ås, Norway
| | - Päivi L. H. Rinne
- Faculty of Biosciences, Department of Plant Sciences, Norwegian University of Life Sciences, Ås, Norway
| | - Morten Skaugen
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences, Ås, Norway
| | - Laju K. Paul
- Faculty of Biosciences, Department of Plant Sciences, Norwegian University of Life Sciences, Ås, Norway
| | - Christiaan van der Schoot
- Faculty of Biosciences, Department of Plant Sciences, Norwegian University of Life Sciences, Ås, Norway
- *Correspondence: Christiaan van der Schoot
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18
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Wu X, Cheng X. Intercellular movement of plant RNA viruses: Targeting replication complexes to the plasmodesma for both accuracy and efficiency. Traffic 2020; 21:725-736. [PMID: 33090653 DOI: 10.1111/tra.12768] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 10/10/2020] [Accepted: 10/10/2020] [Indexed: 02/06/2023]
Abstract
Replication and movement are two critical steps in plant virus infection. Recent advances in the understanding of the architecture and subcellular localization of virus-induced inclusions and the interactions between viral replication complex (VRC) and movement proteins (MPs) allow for the dissection of the intrinsic relationship between replication and movement, which has revealed that recruitment of VRCs to the plasmodesma (PD) via direct or indirect MP-VRC interactions is a common strategy used for cell-to-cell movement by most plant RNA viruses. In this review, we summarize the recent advances in the understanding of virus-induced inclusions and their roles in virus replication and cell-to-cell movement, analyze the advantages of such coreplicational movement from a viral point of view and discuss the possible mechanical force by which MPs drive the movement of virions or viral RNAs through the PD. Finally, we highlight the missing pieces of the puzzle of viral movement that are especially worth investigating in the near future.
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Affiliation(s)
- Xiaoyun Wu
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, China
| | - Xiaofei Cheng
- Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, College of Agriculture, Northeast Agricultural University, Harbin, China
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19
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Wang X, Sager R, Lee JY. Evaluating molecular movement through plasmodesmata. Methods Cell Biol 2020; 160:99-117. [PMID: 32896335 DOI: 10.1016/bs.mcb.2020.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Plasmodesmata are membrane-lined cytoplasmic passageways that facilitate the movement of nutrients and various types of molecules between cells in the plant. They are highly dynamic channels, opening or closing in response to physiological and developmental stimuli or environmental challenges such as biotic and abiotic stresses. Accumulating evidence supports the idea that such dynamic controls occur through integrative cellular mechanisms. Currently, a few fluorescence-based methods are available that allow monitoring changes in molecular movement through plasmodesmata. In this chapter, following a brief introduction to those methods, we provide a detailed step-by-step protocol for the Drop-ANd-See (DANS) assay, which is advantageous when it is desirable to measure plasmodesmal permeability non-invasively, in situ and in real-time. We discuss the experimental conditions one should consider to produce reliable and reproducible DANS results along with troubleshooting ideas.
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Affiliation(s)
- Xu Wang
- Department of Plant Physiology and Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Ross Sager
- Department of Plant and Soil Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, DE, United States
| | - Jung-Youn Lee
- Department of Plant and Soil Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, DE, United States.
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20
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Martins TF, Souza PFN, Alves MS, Silva FDA, Arantes MR, Vasconcelos IM, Oliveira JTA. Identification, characterization, and expression analysis of cowpea (Vigna unguiculata [L.] Walp.) miRNAs in response to cowpea severe mosaic virus (CPSMV) challenge. PLANT CELL REPORTS 2020; 39:1061-1078. [PMID: 32388590 DOI: 10.1007/s00299-020-02548-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/04/2020] [Accepted: 04/25/2020] [Indexed: 06/11/2023]
Abstract
Cowpea miRNAs and Argonaute genes showed differential expression patterns in response to CPSMV challenge Several biotic stresses affect cowpea production and yield. CPSMV stands out for causing severe negative impacts on cowpea. Plants have two main induced immune systems. In the basal system (PTI, PAMP-triggered immunity), plants recognize and respond to conserved molecular patterns associated with pathogens (PAMPs). The second type (ETI, Effector-triggered immunity) is induced after plant recognition of specific factors from pathogens. RNA silencing is another important defense mechanism in plants. Our research group has been using biochemical and proteomic approaches to learn which proteins and pathways are involved and could explain why some cowpea genotypes are resistant whereas others are susceptible to CPSMV. This current study was conducted to determine the role of cowpea miRNA in the interaction between a resistant cowpea genotype (BRS-Marataoã) and CPSMV. Previously identified and deposited plant microRNA sequences were used to find out all possible microRNAs in the cowpea genome. This search detected 617 mature microRNAs, which were distributed in 89 microRNA families. Next, 4 out of these 617 miRNAs and their possible target genes that encode the proteins Kat-p80, DEAD-Box, GST, and SPB9, all involved in the defense response of cowpea to CPSMV, had their expression compared between cowpea leaves uninoculated and inoculated with CPSMV. Additionally, the differential expression of genes that encode the Argonaute (AGO) proteins 1, 2, 4, 6, and 10 is reported. In summary, the studied miRNAs and AGO 2 and AGO4 associated genes showed differential expression patterns in response to CPSMV challenge, which indicate their role in cowpea defense.
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Affiliation(s)
- Thiago F Martins
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil
| | - Pedro F N Souza
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil
| | - Murilo S Alves
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil
| | - Fredy Davi A Silva
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil
| | - Mariana R Arantes
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil
| | - Ilka M Vasconcelos
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil
| | - Jose T A Oliveira
- Department of Biochemistry and Molecular Biology, Federal University of Ceara, Fortaleza, CE, Brazil.
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21
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Pankratenko AV, Atabekova AK, Morozov SY, Solovyev AG. Membrane Contacts in Plasmodesmata: Structural Components and Their Functions. BIOCHEMISTRY (MOSCOW) 2020; 85:531-544. [DOI: 10.1134/s0006297920050028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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22
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Cheng G, Yang Z, Zhang H, Zhang J, Xu J. Remorin interacting with PCaP1 impairs Turnip mosaic virus intercellular movement but is antagonised by VPg. THE NEW PHYTOLOGIST 2020; 225:2122-2139. [PMID: 31657467 DOI: 10.1111/nph.16285] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/18/2019] [Indexed: 06/10/2023]
Abstract
Group 1 Remorins (REMs) are extensively involved in virus trafficking through plasmodesmata (PD). However, their roles in Potyvirus cell-to-cell movement are not known. The plasma membrane (PM)-associated Ca2+ binding protein 1 (PCaP1) interacts with the P3N-PIPO of Turnip mosaic virus (TuMV) and is required for TuMV cell-to-cell movement, but the underlying mechanism remains elusive. The mutant plants with overexpression or knockout of REM1.2 were used to investigate its role in TuMV cell-to-cell movement. Arabidopsis thaliana complementary mutants of pcap1 were used to investigate the role of PCaP1 in TuMV cell-to-cell movement. Yeast-two-hybrid, bimolecular fluorescence complementation, co-immunoprecipitation and RT-qPCR assays were employed to investigate the underlying molecular mechanism. The results show that TuMV-P3N-PIPO recruits PCaP1 to PD and the actin filament-severing activity of PCaP1 is required for TuMV intercellular movement. REM1.2 negatively regulates the cell-to-cell movement of TuMV via competition with PCaP1 for binding actin filaments. As a counteractive response, TuMV mediates REM1.2 degradation via both 26S ubiquitin-proteasome and autophagy pathways through the interaction of VPg with REM1.2 to establish systemic infection in Arabidopsis. This work unveils the actin cytoskeleton and PM nanodomain-associated molecular events underlying the cell-to-cell movement of potyviruses.
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Affiliation(s)
- Guangyuan Cheng
- National Engineering Research Center for Sugarcane, Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Jinshan, Fuzhou, 350002, China
| | - Zongtao Yang
- National Engineering Research Center for Sugarcane, Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Jinshan, Fuzhou, 350002, China
| | - Hai Zhang
- National Engineering Research Center for Sugarcane, Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Jinshan, Fuzhou, 350002, China
| | - Jisen Zhang
- National Engineering Research Center for Sugarcane, Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Jinshan, Fuzhou, 350002, China
- Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Haixia Institute of Science and Technology (HIST), Fujian Agriculture and Forestry University, Jinshan, Fuzhou, 350002, China
| | - Jingsheng Xu
- National Engineering Research Center for Sugarcane, Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Jinshan, Fuzhou, 350002, China
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Plant Lipid Bodies Traffic on Actin to Plasmodesmata Motorized by Myosin XIs. Int J Mol Sci 2020; 21:ijms21041422. [PMID: 32093159 PMCID: PMC7073070 DOI: 10.3390/ijms21041422] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 02/11/2020] [Accepted: 02/14/2020] [Indexed: 02/07/2023] Open
Abstract
Late 19th-century cytologists observed tiny oil drops in shoot parenchyma and seeds, but it was discovered only in 1972 that they were bound by a half unit-membrane. Later, it was found that lipid bodies (LBs) arise from the endoplasmic reticulum. Seeds are known to be packed with static LBs, coated with the LB-specific protein OLEOSIN. As shown here, apices of Populustremula x P. tremuloides also express OLEOSIN genes and produce potentially mobile LBs. In developing buds, PtOLEOSIN (PtOLE) genes were upregulated, especially PtOLE6, concomitant with LB accumulation. To investigate LB mobility and destinations, we transformed Arabidopsis with PtOLE6-eGFP. We found that PtOLE6-eGFP fusion protein co-localized with Nile Red-stained LBs in all cell types. Moreover, PtOLE6-eGFP-tagged LBs targeted plasmodesmata, identified by the callose marker aniline blue. Pharmacological experiments with brefeldin, cytochalasin D, and oryzalin showed that LB-trafficking requires F-actin, implying involvement of myosin motors. In a triple myosin-XI knockout (xi-k/1/2), transformed with PtOLE6-eGFP, trafficking of PtOLE6-eGFP-tagged LBs was severely impaired, confirming that they move on F-actin, motorized by myosin XIs. The data reveal that LBs and OLEOSINs both function in proliferating apices and buds, and that directional trafficking of LBs to plasmodesmata requires the actomyosin system.
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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.
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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
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Li P, Day B. Battlefield Cytoskeleton: Turning the Tide on Plant Immunity. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:25-34. [PMID: 30355064 PMCID: PMC6326859 DOI: 10.1094/mpmi-07-18-0195-fi] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The plant immune system comprises a complex network of signaling processes, regulated not only by classically defined immune components (e.g., resistance genes) but also by a suite of developmental, environmental, abiotic, and biotic-associated factors. In total, it is the sum of these interactions-the connectivity to a seemingly endless array of environments-that ensures proper activation, and control, of a system that is responsible for cell surveillance and response to threats presented by invading pests and pathogens. Over the past decade, the field of plant pathology has witnessed the discovery of numerous points of convergence between immunity, growth, and development, as well as overlap with seemingly disparate processes such as those that underpin plant response to changes in the environment. Toward defining how immune signaling is regulated, recent studies have focused on dissecting the mechanisms that underpin receptor-ligand interactions, phospho-regulation of signaling cascades, and the modulation of host gene expression during infection. As one of the major regulators of these immune signaling cascades, the plant cytoskeleton is the stage from which immune-associated processes are mobilized and oriented and, in this role, it controls the movement of the organelles, proteins, and chemical signals that support plant defense signaling. In short, the cytoskeleton is the battlefield from which pathogens and plants volley virulence and resistance, transforming resistance to susceptibility. Herein, we discuss the role of the eukaryotic cytoskeleton as a platform for the function of the plant immune system.
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Affiliation(s)
- Pai Li
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA
| | - Brad Day
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA
- Michigan State University Plant Resilience Institute, East Lansing, MI 48824, USA
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Wu SW, Kumar R, Iswanto ABB, Kim JY. Callose balancing at plasmodesmata. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:5325-5339. [PMID: 30165704 DOI: 10.1093/jxb/ery317] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/20/2018] [Indexed: 05/19/2023]
Abstract
In plants, communication and molecular exchanges between different cells and tissues are dependent on the apoplastic and symplastic pathways. Symplastic molecular exchanges take place through the plasmodesmata, which connect the cytoplasm of neighboring cells in a highly controlled manner. Callose, a β-1,3-glucan polysaccharide, is a plasmodesmal marker molecule that is deposited in cell walls near the neck zone of plasmodesmata and controls their permeability. During cell differentiation and plant development, and in response to diverse stresses, the level of callose in plasmodesmata is highly regulated by two antagonistic enzymes, callose synthase or glucan synthase-like and β-1,3-glucanase. The diverse modes of regulation by callose synthase and β-1,3-glucanase have been uncovered in the past decades through biochemical, molecular, genetic, and omics methods. This review highlights recent findings regarding the function of plasmodesmal callose and the molecular players involved in callose metabolism, and provides new insight into the mechanisms maintaining plasmodesmal callose homeostasis.
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Affiliation(s)
- Shu-Wei Wu
- Division of Applied Life Science (BK21 Plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Ritesh Kumar
- Division of Applied Life Science (BK21 Plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Arya Bagus Boedi Iswanto
- Division of Applied Life Science (BK21 Plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
| | - Jae-Yean Kim
- Division of Applied Life Science (BK21 Plus program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju, Republic of Korea
- Division of Life Science (CK1 program), Gyeongsang National University, Jinju, Republic of Korea
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Robles Luna G, Peña EJ, Borniego MB, Heinlein M, García ML. Citrus Psorosis Virus Movement Protein Contains an Aspartic Protease Required for Autocleavage and the Formation of Tubule-Like Structures at Plasmodesmata. J Virol 2018; 92:e00355-18. [PMID: 30135122 PMCID: PMC6189509 DOI: 10.1128/jvi.00355-18] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 08/07/2018] [Indexed: 12/15/2022] Open
Abstract
Plant virus cell-to-cell movement is an essential step in viral infections. This process is facilitated by specific virus-encoded movement proteins (MPs), which manipulate the cell wall channels between neighboring cells known as plasmodesmata (PD). Citrus psorosis virus (CPsV) infection in sweet orange involves the formation of tubule-like structures within PD, suggesting that CPsV belongs to "tubule-forming" viruses that encode MPs able to assemble a hollow tubule extending between cells to allow virus movement. Consistent with this hypothesis, we show that the MP of CPsV (MPCPsV) indeed forms tubule-like structures at PD upon transient expression in Nicotiana benthamiana leaves. Tubule formation by MPCPsV depends on its cleavage capacity, mediated by a specific aspartic protease motif present in its primary sequence. A single amino acid mutation in this motif abolishes MPCPsV cleavage, alters the subcellular localization of the protein, and negatively affects its activity in facilitating virus movement. The amino-terminal 34-kDa cleavage product (34KCPsV), but not the 20-kDa fragment (20KCPsV), supports virus movement. Moreover, similar to tubule-forming MPs of other viruses, MPCPsV (and also the 34KCPsV cleavage product) can homooligomerize, interact with PD-located protein 1 (PDLP1), and assemble tubule-like structures at PD by a mechanism dependent on the secretory pathway. 20KCPsV retains the protease activity and is able to cleave a cleavage-deficient MPCPsV in trans Altogether, these results demonstrate that CPsV movement depends on the autolytic cleavage of MPCPsV by an aspartic protease activity, which removes the 20KCPsV protease and thereby releases the 34KCPsV protein for PDLP1-dependent tubule formation at PD.IMPORTANCE Infection by citrus psorosis virus (CPsV) involves a self-cleaving aspartic protease activity within the viral movement protein (MP), which results in the production of two peptides, termed 34KCPsV and 20KCPsV, that carry the MP and viral protease activities, respectively. The underlying protease motif within the MP is also found in the MPs of other members of the Aspiviridae family, suggesting that protease-mediated protein processing represents a conserved mechanism of protein expression in this virus family. The results also demonstrate that CPsV and potentially other ophioviruses move by a tubule-guided mechanism. Although several viruses from different genera were shown to use this mechanism for cell-to-cell movement, our results also demonstrate that this mechanism is controlled by posttranslational protein cleavage. Moreover, given that tubule formation and virus movement could be inhibited by a mutation in the protease motif, targeting the protease activity for inactivation could represent an important approach for ophiovirus control.
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Affiliation(s)
- Gabriel Robles Luna
- Instituto de Biotecnología y Biología Molecular, Facultad de Ciencias Exactas, CONICET UNLP, La Plata, Argentina
| | - Eduardo José Peña
- Instituto de Biotecnología y Biología Molecular, Facultad de Ciencias Exactas, CONICET UNLP, La Plata, Argentina
| | - María Belén Borniego
- Instituto de Biotecnología y Biología Molecular, Facultad de Ciencias Exactas, CONICET UNLP, La Plata, Argentina
| | - Manfred Heinlein
- Université de Strasbourg, CNRS, IBMP UPR 2357, Strasbourg, France
| | - María Laura García
- Instituto de Biotecnología y Biología Molecular, Facultad de Ciencias Exactas, CONICET UNLP, La Plata, Argentina
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Diao M, Ren S, Wang Q, Qian L, Shen J, Liu Y, Huang S. Arabidopsis formin 2 regulates cell-to-cell trafficking by capping and stabilizing actin filaments at plasmodesmata. eLife 2018; 7:e36316. [PMID: 30113309 PMCID: PMC6126924 DOI: 10.7554/elife.36316] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 08/15/2018] [Indexed: 11/13/2022] Open
Abstract
Here, we demonstrate that Arabidopsis thaliana Formin 2 (AtFH2) localizes to plasmodesmata (PD) through its transmembrane domain and is required for normal intercellular trafficking. Although loss-of-function atfh2 mutants have no overt developmental defect, PD's permeability and sensitivity to virus infection are increased in atfh2 plants. Interestingly, AtFH2 functions in a partially redundant manner with its closest homolog AtFH1, which also contains a PD localization signal. Strikingly, targeting of Class I formins to PD was also confirmed in rice, suggesting that the involvement of Class I formins in regulating actin dynamics at PD may be evolutionarily conserved in plants. In vitro biochemical analysis showed that AtFH2 fails to nucleate actin assembly but caps and stabilizes actin filaments. We also demonstrate that the interaction between AtFH2 and actin filaments is crucial for its function in vivo. These data allow us to propose that AtFH2 regulates PD's permeability by anchoring actin filaments to PD.
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Affiliation(s)
- Min Diao
- Center for Plant Biology, School of Life SciencesTsinghua UniversityBeijingChina
- Institute of Botany, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Sulin Ren
- Institute of Botany, Chinese Academy of SciencesBeijingChina
| | - Qiannan Wang
- Center for Plant Biology, School of Life SciencesTsinghua UniversityBeijingChina
| | - Lichao Qian
- Center for Plant Biology, School of Life SciencesTsinghua UniversityBeijingChina
- MOE Key Laboratory of Bioinformatics, Tsinghua-Peking Center for Life SciencesTsinghua UniversityBeijingChina
| | - Jiangfeng Shen
- Center for Plant Biology, School of Life SciencesTsinghua UniversityBeijingChina
| | - Yule Liu
- Center for Plant Biology, School of Life SciencesTsinghua UniversityBeijingChina
- MOE Key Laboratory of Bioinformatics, Tsinghua-Peking Center for Life SciencesTsinghua UniversityBeijingChina
| | - Shanjin Huang
- Center for Plant Biology, School of Life SciencesTsinghua UniversityBeijingChina
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Sasaki N, Takashima E, Nyunoya H. Altered Subcellular Localization of a Tobacco Membrane Raft-Associated Remorin Protein by Tobamovirus Infection and Transient Expression of Viral Replication and Movement Proteins. FRONTIERS IN PLANT SCIENCE 2018; 9:619. [PMID: 29868075 PMCID: PMC5962775 DOI: 10.3389/fpls.2018.00619] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 04/18/2018] [Indexed: 05/20/2023]
Abstract
Remorins are plant specific proteins found in plasma membrane microdomains (termed lipid or membrane rafts) and plasmodesmata. A potato remorin is reported to be involved in negatively regulating potexvirus movement and plasmodesmal permeability. In this study, we isolated cDNAs of tobacco remorins (NtREMs) and examined roles of an NtREM in infection by tomato mosaic virus (ToMV). Subcellular localization analysis using fluorescently tagged NtREM, ToMV, and viral replication and movement proteins (MPs) indicated that virus infection and transient expression of the viral proteins promoted the formation of NtREM aggregates by altering the subcellular distribution of NtREM, which was localized uniformly on the plasma membrane under normal conditions. NtREM aggregates were often observed associated closely with endoplasmic reticulum networks and bodies of the 126K replication and MPs. The bimolecular fluorescence complementation assay indicated that NtREM might interact directly with the MP on the plasma membrane and around plasmodesmata. In addition, transient overexpression of NtREM facilitated ToMV cell-to-cell movement. Based on these results, we discuss possible roles of the tobacco remorin in tobamovirus movement.
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Affiliation(s)
- Nobumitsu Sasaki
- Gene Research Center, Tokyo University of Agriculture and Technology, Fuchu, Japan
- *Correspondence: Nobumitsu Sasaki,
| | - Eita Takashima
- Gene Research Center, Tokyo University of Agriculture and Technology, Fuchu, Japan
| | - Hiroshi Nyunoya
- Gene Research Center, Tokyo University of Agriculture and Technology, Fuchu, Japan
- Faculty of Science and Engineering, Waseda University, Tokyo, Japan
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30
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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.
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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.
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31
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Wang R, Du Z, Bai Z, Liang Z. The interaction between endogenous 30S ribosomal subunit protein S11 and Cucumber mosaic virus LS2b protein affects viral replication, infection and gene silencing suppressor activity. PLoS One 2017; 12:e0182459. [PMID: 28806733 PMCID: PMC5555695 DOI: 10.1371/journal.pone.0182459] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/18/2017] [Indexed: 11/21/2022] Open
Abstract
Cucumber mosaic virus (CMV) is a model virus for plant-virus protein interaction and mechanism research because of its wide distribution, high-level of replication and simple genome structure. The 2b protein is a multifunctional protein encoded by CMV that suppresses RNA silencing-based antiviral defense and contributes to CMV virulence in host plants. In this report, 12 host proteins were identified as CMV LS2b binding partners using the yeast two-hybrid screen system from the Arabidopsis thaliana cDNA library. Among the host proteins, 30S ribosomal subunit protein S11 (RPS11) was selected for further studies. The interaction between LS2b and full-length RPS11 was confirmed using the yeast two-hybrid system. Bimolecular fluorescence complementation (BIFC) assays observed by confocal laser microscopy and Glutathione S-transferase (GST) pull-down assays were used to verify the interaction between endogenous NbRPS11 and viral CMVLS2b both in vivo and in vitro. TRV-based gene silencing vector was used to knockdown NbRPS11 transcription, and immunoblot analysis revealed a decline in infectious viral RNA replication and a decrease in CMV infection in RPS11 down-regulated Nicotiana benthamiana plants. Thus, the knockdown of RPS11 likely inhibited CMV replication and accumulation. The gene silencing suppressor activity of CMV2b protein was reduced by the RPS11 knockdown. This study demonstrated that the function of viral LS2b protein was remarkably affected by the interaction with host RPS11 protein.
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Affiliation(s)
- Ruilin Wang
- Northwest Agriculture and Forestry University, College of Life Science, Yangling, Shaanxi, China
- Xian Mision Bio-Tech, Xian, Shaanxi, China
| | - Zhiyou Du
- Zhejiang Sci-Tech University, College of Life Science, Hangzhou, Zhejiang, China
| | - Zhenqing Bai
- Northwest Agriculture and Forestry University, College of Life Science, Yangling, Shaanxi, China
| | - Zongsuo Liang
- Northwest Agriculture and Forestry University, College of Life Science, Yangling, Shaanxi, China
- Zhejiang Sci-Tech University, College of Life Science, Hangzhou, Zhejiang, China
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32
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Li P, Shu YN, Fu S, Liu YQ, Zhou XP, Liu SS, Wang XW. Vector and nonvector insect feeding reduces subsequent plant susceptibility to virus transmission. THE NEW PHYTOLOGIST 2017; 215:699-710. [PMID: 28382644 DOI: 10.1111/nph.14550] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 02/26/2017] [Indexed: 06/07/2023]
Abstract
The interactions of vector-virus-plant have important ecological and evolutionary implications. While the tripartite interactions have received some attention, little is known about whether vector infestation affects subsequent viral transmission and infection. Working with the whitefly Bemisia tabaci, begomovirus and tobacco/tomato, we demonstrate that pre-infestation of plants by the whitefly vector reduced subsequent plant susceptibility to viral transmission. Pre-infestation by the cotton bollworm, a nonvector of the virus, likewise repressed subsequent viral transmission. The two types of insects, with piercing and chewing mouthparts, respectively, activated different plant signaling pathways in the interactions. Whitefly pre-infestation activated the salicylic acid (SA) signaling pathway, leading to deposition of callose that inhibited begomovirus replication/movement. Although cotton bollworm infestation elicited the jasmonic acid (JA) defense pathway and was beneficial to virus replication, the pre-infested plants repelled whiteflies from feeding and so decreased virus transmission. Experiments using a pharmaceutical approach with plant hormones or a genetic approach using hormone transgenic or mutant plants further showed that SA played a negative but JA played a positive role in begomovirus infection. These novel findings indicate that both vector and nonvector insect feeding of a plant may have substantial negative consequences for ensuing viral transmission and infection.
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Affiliation(s)
- Ping Li
- Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Yan-Ni Shu
- Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Shuai Fu
- Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Yin-Quan Liu
- Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xue-Ping Zhou
- Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Shu-Sheng Liu
- Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xiao-Wei Wang
- Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Sciences, Zhejiang University, Hangzhou, 310058, China
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Nagasato C, Tanaka A, Ito T, Katsaros C, Motomura T. Intercellular translocation of molecules via plasmodesmata in the multiseriate filamentous brown alga, Halopteris congesta (Sphacelariales, Phaeophyceae). JOURNAL OF PHYCOLOGY 2017; 53:333-341. [PMID: 27885652 DOI: 10.1111/jpy.12498] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 09/28/2016] [Indexed: 06/06/2023]
Abstract
Despite the high number of studies on the fine structure of brown algal cells, only limited information is available on the intercelluar transportation of molecules via plasmodesmata in brown algae. In this study, plasmodesmatal permeability of Halopteris congesta was examined by observing the translocation of microinjected fluorescent tracers of different molecular sizes. The tip region of H. congesta consists of a cylindrical apical cell, while the basal region is multiseriate. Fluorescein isothiocyanate-dextran (FD; 3, 10, and 20 kDa) and recombinant green fluorescent protein (27 kDa) were injected into the apical cell and were observed to diffuse into the neighboring cells. FD of 40 kDa was detected only in the injected apical cell. The plasmodesmatal size exclusion limit was considered to be more than 20 kDa and less than 40 kDa. The extent of translocation of 3 and 10 kDa FD from the apical to neighboring cells 2 h postinjection was estimated based on the fluorescence intensity. It was suggested that the diffusing capacity of plasmodesmata varied according to molecular size. In order to examine acropetal and/or basipetal direction of molecular movement, 3 and 10 kDa FD were injected into the third cell from the apical cell. Successive observations indicated that the diffusion of fluorescence in the acropetal direction took longer than that in the basipetal direction. No ultrastructural difference in plasmodesmata was noted among the cross walls.
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Affiliation(s)
- Chikako Nagasato
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0013, Japan
| | - Atsuko Tanaka
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0013, Japan
| | - Toshiaki Ito
- Electron Microscope Laboratory, Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan
| | - Christos Katsaros
- Department of Botany, Faculty of Biology, University of Athens, 15784, Athens, Greece
| | - Taizo Motomura
- Muroran Marine Station, Field Science Center for Northern Biosphere, Hokkaido University, Muroran, 051-0013, Japan
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Alazem M, Lin NS. Antiviral Roles of Abscisic Acid in Plants. FRONTIERS IN PLANT SCIENCE 2017; 8:1760. [PMID: 29075279 PMCID: PMC5641568 DOI: 10.3389/fpls.2017.01760] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 09/26/2017] [Indexed: 05/18/2023]
Abstract
Abscisic acid (ABA) is a key hormone involved in tuning responses to several abiotic stresses and also has remarkable impacts on plant defense against various pathogens. The roles of ABA in plant defense against bacteria and fungi are multifaceted, inducing or reducing defense responses depending on its time of action. However, ABA induces different resistance mechanisms to viruses regardless of the induction time. Recent studies have linked ABA to the antiviral silencing pathway, which interferes with virus accumulation, and the micro RNA (miRNA) pathway through which ABA affects the maturation and stability of miRNAs. ABA also induces callose deposition at plasmodesmata, a mechanism that limits viral cell-to-cell movement. Bamboo mosaic virus (BaMV) is a member of the potexvirus group and is one of the most studied viruses in terms of the effects of ABA on its accumulation and resistance. In this review, we summarize how ABA interferes with the accumulation and movement of BaMV and other viruses. We also highlight aspects of ABA that may have an effect on other types of resistance and that require further investigation.
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Zhao J, Xin H, Cao L, Huang X, Shi C, Zhao P, Fu Y, Sun MX. NtDRP is necessary for accurate zygotic division orientation and differentiation of basal cell lineage toward suspensor formation. THE NEW PHYTOLOGIST 2016; 212:598-612. [PMID: 27348863 DOI: 10.1111/nph.14060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 05/14/2016] [Indexed: 05/08/2023]
Abstract
Plant embryogenesis begins with an asymmetric division of the zygote, producing apical and basal cells with distinct cell fates. The asymmetric zygote division is thought to be critical for embryo pattern formation; however, the molecular mechanisms regulating this process, especially maintaining the accurate position and proper orientation of cell division plane, remain poorly understood. Here, we report that a dynamin-related protein in Nicotiana tabacum, NtDRP, plays a critical role in maintaining orientation of zygotic division plane. Down-regulation of NtDRP caused zygotic cell division to occur in different, incorrect orientations and resulted in disruption of suspensor formation, and even development of twin embryos. The basal cell lineage totally integrated with the apical cell lineage into an embryo-like structure, suggesting that NtDRP is essential to accurate zygotic division orientation and differentiation of basal cell lineage toward suspensor formation. We also reveal that NtDRP plays its role by modulating microtubule spatial organization and spindle orientation during early embryogenesis. Thus, we revealed that NtDRP is involved in orientation of the asymmetric zygotic division and differentiation of distinct suspensor and embryo domains, as well as subsequent embryo pattern formation.
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Affiliation(s)
- Jing Zhao
- Department of Cell and Developmental Biology, College of Life Science, State Key Laboratory of Hybrid Rice, Wuhan University, Wuhan, 430072, China
| | - Haiping Xin
- Department of Cell and Developmental Biology, College of Life Science, State Key Laboratory of Hybrid Rice, Wuhan University, Wuhan, 430072, China
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan, 430074, China
| | - Lingyan Cao
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaorong Huang
- Department of Cell and Developmental Biology, College of Life Science, State Key Laboratory of Hybrid Rice, Wuhan University, Wuhan, 430072, China
| | - Ce Shi
- Department of Cell and Developmental Biology, College of Life Science, State Key Laboratory of Hybrid Rice, Wuhan University, Wuhan, 430072, China
| | - Peng Zhao
- Department of Cell and Developmental Biology, College of Life Science, State Key Laboratory of Hybrid Rice, Wuhan University, Wuhan, 430072, China
| | - Ying Fu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Meng-Xiang Sun
- Department of Cell and Developmental Biology, College of Life Science, State Key Laboratory of Hybrid Rice, Wuhan University, Wuhan, 430072, China.
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Kumari R, Kumar S, Singh L, Hallan V. Movement Protein of Cucumber Mosaic Virus Associates with Apoplastic Ascorbate Oxidase. PLoS One 2016; 11:e0163320. [PMID: 27668429 PMCID: PMC5036820 DOI: 10.1371/journal.pone.0163320] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 09/07/2016] [Indexed: 01/13/2023] Open
Abstract
Plant viral movement proteins facilitate virion movement mainly through interaction with a number of factors from the host. We report the association of a cell wall localized ascorbate oxidase (CsAO4) from Cucumis sativus with the movement protein (MP) of Cucumber mosaic virus (CMV). This was identified first in a yeast two-hybrid screen and validated by in vivo pull down and bimolecular fluorescence complementation (BiFC) assays. The BiFC assay showed localization of the bimolecular complexes of these proteins around the cell wall periphery as punctate spots. The expression of CsAO4 was induced during the initial infection period (up to 72 h) in CMV infected Nicotiana benthamiana plants. To functionally validate its role in viral spread, we analyzed the virus accumulation in CsAO4 overexpressing Arabidopsis thaliana and transiently silenced N. benthamiana plants (through a Tobacco rattle virus vector). Overexpression had no evident effect on virus accumulation in upper non-inoculated leaves of transgenic lines in comparison to WT plants at 7 days post inoculation (dpi). However, knockdown resulted in reduced CMV accumulation in systemic (non-inoculated) leaves of NbΔAO-pTRV2 silenced plants as compared to TRV inoculated control plants at 5 dpi (up to 1.3 fold difference). In addition, functional validation supported the importance of AO in plant development. These findings suggest that AO and viral MP interaction helps in early viral movement; however, it had no major effect on viral accumulation after 7 dpi. This study suggests that initial induction of expression of AO on virus infection and its association with viral MP helps both towards targeting of the MP to the apoplast and disrupting formation of functional AO dimers for spread of virus to nearby cells, reducing the redox defense of the plant during initial stages of infection.
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Affiliation(s)
- Reenu Kumari
- Plant Virology lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India
- Department of Biotechnology, Guru Nanak Dev University, Amritsar, 143005, India
| | - Surender Kumar
- Plant Virology lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT) Campus, Palampur, India
| | - Lakhmir Singh
- Department of Biotechnology, DAV University, Sarmastpur, Jalandhar, 144012, Punjab, India
| | - Vipin Hallan
- Plant Virology lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur, 176061, Himachal Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Institute of Himalayan Bioresource Technology (CSIR-IHBT) Campus, Palampur, India
- * E-mail:
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Borniego MB, Karlin D, Peña EJ, Robles Luna G, García ML. Bioinformatic and mutational analysis of ophiovirus movement proteins, belonging to the 30K superfamily. Virology 2016; 498:172-180. [PMID: 27596536 DOI: 10.1016/j.virol.2016.08.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 08/19/2016] [Accepted: 08/27/2016] [Indexed: 01/21/2023]
Abstract
Ophioviridae is a family of segmented, negative-sense, single-stranded RNA plant viruses. We showed that their cell-to-cell movement protein (MP) is an isolated member of the 30K MP superfamily with a unique structural organization. All 30K MPs share a core domain that contains a nearly-invariant signature aspartate. We examined its role in the MP of Citrus psorosis virus (CPsV) and Mirafiori lettuce big-vein virus (MiLBVV). Alanine substitution of this aspartate prevented plasmodesmata accumulation of MP(MiLBVV), while MP(CPsV) was not affected. The capacity of ophiovirus MPs to increase the plasmodesmata size exclusion limit and non-cell autonomous protein feature was abolished in both mutants. To investigate the role of the signature aspartate in cell-to-cell movement, we constructed a new movement-deficient Tobacco mosaic virus vector used for trans-complementation assays. We showed that both ophiovirus MP mutants lack the cell-to-cell movement capacity, confirming that this signature aspartate is essential for viral cell-to-cell movement.
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Affiliation(s)
- María Belén Borniego
- Instituto de Biotecnología y Biología Molecular, CCT-La Plata CONICET, Fac. Cs. Exactas, U.N.L.P., Calles 49 y 115, La Plata, Argentina
| | - David Karlin
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK; The Division of Structural Biology, Henry Wellcome Building, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Eduardo José Peña
- Instituto de Biotecnología y Biología Molecular, CCT-La Plata CONICET, Fac. Cs. Exactas, U.N.L.P., Calles 49 y 115, La Plata, Argentina
| | - 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
| | - María Laura García
- Instituto de Biotecnología y Biología Molecular, CCT-La Plata CONICET, Fac. Cs. Exactas, U.N.L.P., Calles 49 y 115, La Plata, Argentina.
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Tilsner J, Nicolas W, Rosado A, Bayer EM. Staying Tight: Plasmodesmal Membrane Contact Sites and the Control of Cell-to-Cell Connectivity in Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:337-64. [PMID: 26905652 DOI: 10.1146/annurev-arplant-043015-111840] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Multicellularity differs in plants and animals in that the cytoplasm, plasma membrane, and endomembrane of plants are connected between cells through plasmodesmal pores. Plasmodesmata (PDs) are essential for plant life and serve as conduits for the transport of proteins, small RNAs, hormones, and metabolites during developmental and defense signaling. They are also the only pathways available for viruses to spread within plant hosts. The membrane organization of PDs is unique, characterized by the close apposition of the endoplasmic reticulum and the plasma membrane and spoke-like filamentous structures linking the two membranes, which define PDs as membrane contact sites (MCSs). This specialized membrane arrangement is likely critical for PD function. Here, we review how PDs govern developmental and defensive signaling in plants, compare them with other types of MCSs, and discuss in detail the potential functional significance of the MCS nature of PDs.
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Affiliation(s)
- Jens Tilsner
- Biomedical Sciences Research Complex, University of St Andrews, Fife KY16 9ST, United Kingdom;
- Cell and Molecular Sciences, The James Hutton Institute, Dundee DD2 5DA, United Kingdom
| | - William Nicolas
- Laboratory of Membrane Biogenesis, UMR5200 CNRS, University of Bordeaux, 33883 Villenave d'Ornon Cedex, France; ,
| | - Abel Rosado
- Department of Botany, Faculty of Sciences, University of British Columbia, Vancouver V6T 1Z4, Canada;
| | - Emmanuelle M Bayer
- Laboratory of Membrane Biogenesis, UMR5200 CNRS, University of Bordeaux, 33883 Villenave d'Ornon Cedex, France; ,
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Biotechnological aspects of cytoskeletal regulation in plants. Biotechnol Adv 2015; 33:1043-62. [DOI: 10.1016/j.biotechadv.2015.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 03/03/2015] [Accepted: 03/09/2015] [Indexed: 11/23/2022]
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40
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Bak A, Folimonova SY. The conundrum of a unique protein encoded by citrus tristeza virus that is dispensable for infection of most hosts yet shows characteristics of a viral movement protein. Virology 2015; 485:86-95. [PMID: 26210077 DOI: 10.1016/j.virol.2015.07.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 07/03/2015] [Accepted: 07/04/2015] [Indexed: 11/22/2022]
Abstract
Citrus tristeza virus (CTV), one of the most economically important viruses, produces a unique protein, p33, which is encoded only in the genomes of isolates of CTV. Recently, we demonstrated that membrane association of the p33 protein confers virus ability to extend its host range. In this work we show that p33 shares characteristics of viral movement proteins. Upon expression in a host cell, the protein localizes to plasmodesmata and displays the ability to form extracellular tubules. Furthermore, p33 appears to traffic via the cellular secretory pathway and the actin network to plasmodesmata locations and is likely being recycled through the endocytic pathway. Finally, our study reveals that p33 colocalizes with a putative movement protein of CTV, the p6 protein. These results suggest a potential role of p33 as a noncanonical viral movement protein, which mediates virus translocation in the specific hosts.
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Affiliation(s)
- Aurélie Bak
- University of Florida, Plant Pathology Department, Gainesville, FL 32611, USA
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Singh P, Savithri HS. GBNV encoded movement protein (NSm) remodels ER network via C-terminal coiled coil domain. Virology 2015; 482:133-46. [PMID: 25863878 DOI: 10.1016/j.virol.2015.01.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 01/24/2015] [Accepted: 01/31/2015] [Indexed: 02/03/2023]
Abstract
Plant viruses exploit the host machinery for targeting the viral genome-movement protein complex to plasmodesmata (PD). The mechanism by which the non-structural protein m (NSm) of Groundnut bud necrosis virus (GBNV) is targeted to PD was investigated using Agrobacterium mediated transient expression of NSm and its fusion proteins in Nicotiana benthamiana. GFP:NSm formed punctuate structures that colocalized with mCherry:plasmodesmata localized protein 1a (PDLP 1a) confirming that GBNV NSm localizes to PD. Unlike in other movement proteins, the C-terminal coiled coil domain of GBNV NSm was shown to be involved in the localization of NSm to PD, as deletion of this domain resulted in the cytoplasmic localization of NSm. Treatment with Brefeldin A demonstrated the role of ER in targeting GFP NSm to PD. Furthermore, mCherry:NSm co-localized with ER-GFP (endoplasmic reticulum targeting peptide (HDEL peptide fused with GFP). Co-expression of NSm with ER-GFP showed that the ER-network was transformed into vesicles indicating that NSm interacts with ER and remodels it. Mutations in the conserved hydrophobic region of NSm (residues 130-138) did not abolish the formation of vesicles. Additionally, the conserved prolines at positions 140 and 142 were found to be essential for targeting the vesicles to the cell membrane. Further, systematic deletion of amino acid residues from N- and C-terminus demonstrated that N-terminal 203 amino acids are dispensable for the vesicle formation. On the other hand, the C-terminal coiled coil domain when expressed alone could also form vesicles. These results suggest that GBNV NSm remodels the ER network by forming vesicles via its interaction through the C-terminal coiled coil domain. Interestingly, NSm interacts with NP in vitro and coexpression of these two proteins in planta resulted in the relocalization of NP to PD and this relocalization was abolished when the N-terminal unfolded region of NSm was deleted. Thus, the NSm interacts with NP via its N-terminal unfolded region and the NSm-NP complex could in turn interact with the ER membrane via the C-terminal coiled coil domain of NSm to form vesicles that are targeted to PD and there by assist the cell to cell movement of the viral genome complex.
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Affiliation(s)
- Pratibha Singh
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - H S Savithri
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India.
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Nováková S, Flores-Ramírez G, Glasa M, Danchenko M, Fiala R, Skultety L. Partially resistant Cucurbita pepo showed late onset of the Zucchini yellow mosaic virus infection due to rapid activation of defense mechanisms as compared to susceptible cultivar. FRONTIERS IN PLANT SCIENCE 2015; 6:263. [PMID: 25972878 PMCID: PMC4411989 DOI: 10.3389/fpls.2015.00263] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 04/02/2015] [Indexed: 05/29/2023]
Abstract
Zucchini yellow mosaic virus (ZYMV) is an emerging viral pathogen in cucurbit-growing areas wordwide. Infection causes significant yield losses in several species of the family Cucurbitaceae. To identify proteins potentially involved with resistance toward infection by the severe ZYMV-H isolate, two Cucurbita pepo cultivars (Zelena susceptible and Jaguar partially resistant) were analyzed using a two-dimensional gel electrophoresis-based proteomic approach. Initial symptoms on leaves (clearing veins) developed 6-7 days post-inoculation (dpi) in the susceptible C. pepo cv. Zelena. In contrast, similar symptoms appeared on the leaves of partially resistant C. pepo cv. Jaguar only after 15 dpi. This finding was confirmed by immune-blot analysis which showed higher levels of viral proteins at 6 dpi in the susceptible cultivar. Leaf proteome analyses revealed 28 and 31 spots differentially abundant between cultivars at 6 and 15 dpi, respectively. The variance early in infection can be attributed to a rapid activation of proteins involved with redox homeostasis in the partially resistant cultivar. Changes in the proteome of the susceptible cultivar are related to the cytoskeleton and photosynthesis.
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Affiliation(s)
| | | | - Miroslav Glasa
- Institute of Virology, Slovak Academy of SciencesBratislava, Slovakia
| | - Maksym Danchenko
- Institute of Virology, Slovak Academy of SciencesBratislava, Slovakia
| | - Roderik Fiala
- Institute of Botany, Slovak Academy of SciencesBratislava, Slovakia
| | - Ludovit Skultety
- Institute of Virology, Slovak Academy of SciencesBratislava, Slovakia
- Institute of Microbiology, Academy of Sciences of Czech RepublicPrague, Czech Republic
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Mushegian AR, Elena SF. Evolution of plant virus movement proteins from the 30K superfamily and of their homologs integrated in plant genomes. Virology 2015; 476:304-315. [DOI: 10.1016/j.virol.2014.12.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 12/04/2014] [Accepted: 12/06/2014] [Indexed: 12/01/2022]
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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.
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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,
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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.
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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
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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: 106] [Impact Index Per Article: 10.6] [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.
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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
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Allie F, Pierce EJ, Okoniewski MJ, Rey C. Transcriptional analysis of South African cassava mosaic virus-infected susceptible and tolerant landraces of cassava highlights differences in resistance, basal defense and cell wall associated genes during infection. BMC Genomics 2014; 15:1006. [PMID: 25412561 PMCID: PMC4253015 DOI: 10.1186/1471-2164-15-1006] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 10/23/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cassava mosaic disease is caused by several distinct geminivirus species, including South African cassava mosaic virus-[South Africa:99] (SACMV). To date, there is limited gene regulation information on viral stress responses in cassava, and global transcriptome profiling in SACMV-infected cassava represents an important step towards understanding natural host responses to plant geminiviruses. RESULTS A RNA-seq time course (12, 32 and 67 dpi) study, monitoring gene expression in SACMV-challenged susceptible (T200) and tolerant (TME3) cassava landraces, was performed using the Applied Biosystems (ABI) SOLiD next-generation sequencing platform. The multiplexed paired end sequencing run produced a total of 523 MB and 693 MB of paired-end reads for SACMV-infected susceptible and tolerant cDNA libraries, respectively. Of these, approximately 50.7% of the T200 reads and 55.06% of TME3 reads mapped to the cassava reference genome available in phytozome. Using a log2 fold cut-off (p<0.05), comparative analysis between the six normalized cDNA libraries showed that 4181 and 1008 transcripts in total were differentially expressed in T200 and TME3, respectively, across 12, 32 and 67 days post infection, compared to mock-inoculated. The number of responsive transcripts increased dramatically from 12 to 32 dpi in both cultivars, but in contrast, in T200 the levels did not change significantly at 67 dpi, while in TME3 they declined. GOslim functional groups illustrated that differentially expressed genes in T200 and TME3 were overrepresented in the cellular component category for stress-related genes, plasma membrane and nucleus. Alterations in the expression of other interesting genes such as transcription factors, resistance (R) genes, and histone/DNA methylation-associated genes, were observed. KEGG pathway analysis uncovered important altered metabolic pathways, including phenylpropanoid biosynthesis, sucrose and starch metabolism, and plant hormone signalling. CONCLUSIONS Molecular mechanisms for TME3 tolerance are proposed, and differences in patterns and levels of transcriptome profiling between T200 and TME3 with susceptible and tolerant phenotypes, respectively, support the hypothesis that viruses rearrange their molecular interactions in adapting to hosts with different genetic backgrounds.
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Affiliation(s)
- Farhahna Allie
- />School of Molecular and Cell Biology, University of the Witwatersrand, 1 Jan Smuts Ave, Braamfontein, Johannesburg, 2000 South Africa
| | - Erica J Pierce
- />School of Molecular and Cell Biology, University of the Witwatersrand, 1 Jan Smuts Ave, Braamfontein, Johannesburg, 2000 South Africa
| | - Michal J Okoniewski
- />Functional Genomics Center, Zurich, UNI ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Chrissie Rey
- />School of Molecular and Cell Biology, University of the Witwatersrand, 1 Jan Smuts Ave, Braamfontein, Johannesburg, 2000 South Africa
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Gui J, Liu C, Shen J, Li L. Grain setting defect1, encoding a remorin protein, affects the grain setting in rice through regulating plasmodesmatal conductance. PLANT PHYSIOLOGY 2014; 166:1463-78. [PMID: 25253885 PMCID: PMC4226345 DOI: 10.1104/pp.114.246769] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 09/23/2014] [Indexed: 05/20/2023]
Abstract
Effective grain filling is one of the key determinants of grain setting in rice (Oryza sativa). Grain setting defect1 (GSD1), which encodes a putative remorin protein, was found to affect grain setting in rice. Investigation of the phenotype of a transfer DNA insertion mutant (gsd1-Dominant) with enhanced GSD1 expression revealed abnormalities including a reduced grain setting rate, accumulation of carbohydrates in leaves, and lower soluble sugar content in the phloem exudates. GSD1 was found to be specifically expressed in the plasma membrane and plasmodesmata (PD) of phloem companion cells. Experimental evidence suggests that the phenotype of the gsd1-Dominant mutant is caused by defects in the grain-filling process as a result of the impaired transport of carbohydrates from the photosynthetic site to the phloem. GSD1 functioned in affecting PD conductance by interacting with rice ACTIN1 in association with the PD callose binding protein1. Together, our results suggest that GSD1 may play a role in regulating photoassimilate translocation through the symplastic pathway to impact grain setting in rice.
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Affiliation(s)
- Jinshan Gui
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Chang Liu
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Junhui Shen
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Laigeng Li
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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49
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Probing plasmodesmata function with biochemical inhibitors. Methods Mol Biol 2014; 1217:199-227. [PMID: 25287206 DOI: 10.1007/978-1-4939-1523-1_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
To investigate plasmodesmata (PD) function, a useful technique is to monitor the effect on cell-to-cell transport of applying an inhibitor of a physiological process, protein, or other cell component of interest. Changes in PD transport can then be monitored in one of several ways, most commonly by measuring the cell-to-cell movement of fluorescent tracer dyes or of free fluorescent proteins. Effects on PD structure can be detected in thin sections of embedded tissue observed using an electron microscope, most commonly a Transmission Electron Microscope (TEM). This chapter outlines commonly used inhibitors, methods for treating different tissues, how to detect altered cell-to-cell transport and PD structure, and important caveats.
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Balasubramaniam M, Kim BS, Hutchens-Williams HM, Loesch-Fries LS. The photosystem II oxygen-evolving complex protein PsbP interacts with the coat protein of Alfalfa mosaic virus and inhibits virus replication. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2014; 27:1107-18. [PMID: 24940990 DOI: 10.1094/mpmi-02-14-0035-r] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Alfalfa mosaic virus (AMV) coat protein (CP) is essential for many steps in virus replication from early infection to encapsidation. However, the identity and functional relevance of cellular factors that interact with CP remain unknown. In an unbiased yeast two-hybrid screen for CP-interacting Arabidopsis proteins, we identified several novel protein interactions that could potentially modulate AMV replication. In this report, we focus on one of the novel CP-binding partners, the Arabidopsis PsbP protein, which is a nuclear-encoded component of the oxygen-evolving complex of photosystem II. We validated the protein interaction in vitro with pull-down assays, in planta with bimolecular fluorescence complementation assays, and during virus infection by co-immunoprecipitations. CP interacted with the chloroplast-targeted PsbP in the cytosol and mutations that prevented the dimerization of CP abolished this interaction. Importantly, PsbP overexpression markedly reduced virus accumulation in infected leaves. Taken together, our findings demonstrate that AMV CP dimers interact with the chloroplast protein PsbP, suggesting a potential sequestration strategy that may preempt the generation of any PsbP-mediated antiviral state.
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