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Morina F, Mijovilovich A, Mishra A, Brückner D, Vujić B, Bokhari SNH, Špak J, Falkenberg G, Küpper H. Cadmium and Zn hyperaccumulation provide efficient constitutive defense against Turnip yellow mosaic virus infection in Noccaea caerulescens. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2023; 336:111864. [PMID: 37689279 DOI: 10.1016/j.plantsci.2023.111864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/25/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023]
Abstract
To understand the role of Zn and Cd in anti-viral defence, Zn/Cd hyperaccumulator Noccaea caerulescens plants grown with deficient (0.3 µM), replete (10 µM) and excess (100 µM) Zn2+ and Cd (10 µM Zn2+ + 1 µM Cd2+) were infected with Turnip yellow mosaic virus (TYMV). Gas exchange and chlorophyll fluorescence kinetics analyses demonstrated direct TYMV effects on photosynthetic light reactions but N. caerulescens was more resistant against TYMV than the previously studied non-hyperaccumulator N. ochroleucum. Virus abundance and photosynthesis inhibition were the lowest in the high Zn and Cd treatments. RNAseq analysis of 10 µM Zn2+ plants revealed TYMV-induced upregulation of Ca transporters, chloroplastic ZTP29 and defence genes, but none of those that are known to be strongly involved in hyperaccumulation. Synchrotron µ-XRF tomography, however, showed that Zn hyperaccumulation remained strongest in vacuoles of epidermal storage cells regardless of infection. This was in contrast to N. ochroleucum, where apoplastic Zn drastically increased in response to TYMV. These results suggest that the antiviral response of N. caerulescens is less induced by the onset of this biotic stress, but it is rather a permanent resistant state of the plant. Real-time qPCR revealed upregulation of ferritin in Zn10 infected plants, suggesting Fe deprivation as a virus defence strategy under suboptimal Zn supply.
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Affiliation(s)
- Filis Morina
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
| | - Ana Mijovilovich
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
| | - Archana Mishra
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
| | - Dennis Brückner
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany; University of Hamburg, Department of Physics, Jungiusstr. 9, 20355 Hamburg, Germany; Ruhr-Universität Bochum, Faculty of Chemistry and Biochemistry, Universitätsstr. 150, 44801 Bochum, Germany.
| | - Bojan Vujić
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
| | - Syed Nadeem Hussain Bokhari
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
| | - Josef Špak
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
| | - Gerald Falkenberg
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
| | - Hendrik Küpper
- Czech Academy of Sciences, Biology Centre, Institute of Plant Molecular Biology, Laboratory of Plant Biophysics & Biochemistry, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, Department of Experimental Plant Biology, Branišovská 31/1160, 370 05 České Budějovice, Czech Republic.
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Rattan UK, Kumar S, Kumari R, Bharti M, Hallan V. Homeobox 27, a Homeodomain Transcription Factor, Confers Tolerances to CMV by Associating with Cucumber Mosaic Virus 2b Protein. Pathogens 2022; 11:pathogens11070788. [PMID: 35890032 PMCID: PMC9323240 DOI: 10.3390/pathogens11070788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/06/2022] [Accepted: 07/06/2022] [Indexed: 11/16/2022] Open
Abstract
Transcription factors (TFs) play an important role in plant development; however, their role during viral infection largely remains unknown. The present study was designed to uncover the role transcription factors play in Cucumber mosaic virus (CMV) infection. During the screening of an Arabidopsis thaliana (Col-0) transcription factor library, using the CMV 2b protein as bait in the yeast two-hybrid system, the 2b protein interacted with Homeobox protein 27 (HB27). HB27 belongs to the zinc finger homeodomain family and is known to have a regulatory role in flower development, and responses to biotic and abiotic stress. The interaction between CMV 2b and HB27 proteins was further validated using in planta (bimolecular fluorescence complementation assay) and in vitro far-Western blotting (FWB) methods. In the bimolecular fluorescence complementation assay, these proteins reconstituted YFP fluorescence in the nucleus and the cytoplasmic region as small fluorescent dots. In FWB, positive interaction was detected using bait anti-MYC antibody on the target HB27-HA protein. During CMV infection, upregulation (~3-fold) of the HB27 transcript was observed at 14 days post-infection (dpi) in A. thaliana plants, and expression declined to the same as healthy plants at 21 dpi. To understand the role of the HB27 protein during CMV infection, virus accumulation was determined in HB27-overexpressing (HB27 OE) and knockout mutants. In HB27-overexpressing lines, infected plants developed mild symptoms, accumulating a lower virus titer at 21 dpi compared to wild-type plants. Additionally, knockout HB27 mutants had more severe symptoms and a higher viral accumulation than wild-type plants. These results indicate that HB27 plays an important role in the regulation of plant defense against plant virus infection.
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Affiliation(s)
- Usha Kumari Rattan
- Plant Virology Lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, India; (U.K.R.); (S.K.); (R.K.); (M.B.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Surender Kumar
- Plant Virology Lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, India; (U.K.R.); (S.K.); (R.K.); (M.B.)
| | - Reenu Kumari
- Plant Virology Lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, India; (U.K.R.); (S.K.); (R.K.); (M.B.)
- College of Horticulture and Forestry, Dr. Y. S. Parmar University of Horticulture and Forestry, Thunag, Mandi 175048, India
| | - Monika Bharti
- Plant Virology Lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, India; (U.K.R.); (S.K.); (R.K.); (M.B.)
| | - Vipin Hallan
- Plant Virology Lab, CSIR-Institute of Himalayan Bioresource Technology, Palampur 176061, India; (U.K.R.); (S.K.); (R.K.); (M.B.)
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- Correspondence: ; Tel.: +91-1894-233338; Fax: +91-1894-230433
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Ke YD, Huang YW, Viswanath KK, Hu CC, Yeh CM, Mitsuda N, Lin NS, Hsu YH. NbNAC42 and NbZFP3 Transcription Factors Regulate the Virus Inducible NbAGO5 Promoter in Nicotiana benthamiana. FRONTIERS IN PLANT SCIENCE 2022; 13:924482. [PMID: 35812928 PMCID: PMC9261433 DOI: 10.3389/fpls.2022.924482] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/23/2022] [Indexed: 05/27/2023]
Abstract
Plant argonautes (AGOs) play important roles in the defense responses against viruses. The expression of Nicotiana benthamiana AGO5 gene (NbAGO5) is highly induced by Bamboo mosaic virus (BaMV) infection; however, the underlying mechanisms remain elusive. In this study, we have analyzed the potential promoter activities of NbAGO5 and its interactions with viral proteins by using a 2,000 bp fragment, designated as PN1, upstream to the translation initiation of NbAGO5. PN1 and seven serial 5'-deletion mutants (PN2-PN8) were fused with a β-glucuronidase (GUS) reporter and introduced into the N. benthamiana genome by Agrobacterium-mediated transformation for further characterization. It was found that PN4-GUS transgenic plants were able to drive strong GUS expression in the whole plant. In the virus infection tests, the GUS activity was strongly induced in PN4-GUS transgenic plants after being challenged with potexviruses. Infiltration of the transgenic plants individually with BaMV coat protein (CP) or triple gene block protein 1 (TGBp1) revealed that only TGBp1 was crucial for inducing the NbAGO5 promoter. To identify the factors responsible for controlling the activity of the NbAGO5 promoter, we employed yeast one-hybrid screening on a transcription factor cDNA library. The result showed that NbNAC42 and NbZFP3 could directly bind the 704 bp promoter regions of NbAGO5. By using overexpressing and virus-induced gene silencing techniques, we found that NbNAC42 and NbZFP3 regulated and downregulated, respectively, the expression of the NbAGO5 gene. Upon virus infection, NbNAC42 played an important role in regulating the expression of NbAGO5. Together, these results provide new insights into the modulation of the defense mechanism of N. benthamiana against viruses. This virus inducible promoter could be an ideal candidate to drive the target gene expression that could improve the anti-virus abilities of crops in the future.
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Affiliation(s)
- Yuan-Dun Ke
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Ying-Wen Huang
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | | | - Chung-Chi Hu
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Chuan-Ming Yeh
- Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Nobutaka Mitsuda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Na-Sheng Lin
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei City, Taiwan
| | - Yau-Heiu Hsu
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
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Yoon JY, Palukaitis P. Cucumber Mosaic Virus 1a Protein Interacts with the Tobacco SHE1 Transcription Factor and Partitions between the Nucleus and the Tonoplast Membrane. THE PLANT PATHOLOGY JOURNAL 2021; 37:182-193. [PMID: 33866760 PMCID: PMC8053847 DOI: 10.5423/ppj.ft.03.2021.0045] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 03/14/2021] [Indexed: 06/12/2023]
Abstract
The transcription factor SHE1 was identified as an interacting partner with the cucumber mosaic virus (CMV) 1a protein in the yeast two-hybrid system, by a pull-down assay, and via bimolecular fluorescent complementation. Using fluorescent-tagged proteins and confocal microscopy, the CMV 1a protein itself was found distributed predominantly between the nucleus and the tonoplast membrane, although it was also found in speckles in the cytoplasm. The SHE1 protein was localized in the nucleus, but in the presence of the CMV 1a protein was partitioned between the nucleus and the tonoplast membrane. SHE1 expression was induced by infection of tobacco with four tested viruses: CMV, tobacco mosaic virus, potato virus X and potato virus Y. Transgenic tobacco expressing the CMV 1a protein showed constitutive expression of SHE1, indicating that the CMV 1a protein may be responsible for its induction. However, previously, such plants also were shown to have less resistance to local and systemic movement of tobacco mosaic virus (TMV) expressing the green fluorescent protein, suggesting that the CMV 1a protein may act to prevent the function of the SHE1 protein. SHE1 is a member of the AP2/ERF class of transcription factors and is conserved in sequence in several Nicotiana species, although two clades of SHE1 could be discerned, including both different Nicotiana species and cultivars of tobacco, varying by the presence of particular insertions or deletions.
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Affiliation(s)
- Ju-Yeon Yoon
- Virology Unit, Division of Horticultural and Herbal Crop Environment, National Institute of Horticultural and Herbal Science, Rural Development Administration, Wanju 55365,
Korea
| | - Peter Palukaitis
- Department of Horticulture Sciences, Seoul Women's University, Seoul 01797,
Korea
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Wang X, Ma J, Jin X, Yue N, Gao P, Mai KKK, Wang XB, Li D, Kang BH, Zhang Y. Three-dimensional reconstruction and comparison of vacuolar membranes in response to viral infection. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:353-364. [PMID: 33085164 DOI: 10.1111/jipb.13027] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
The vacuole is a unique plant organelle that plays an important role in maintaining cellular homeostasis under various environmental stress conditions. However, the effects of biotic stress on vacuole structure has not been examined using three-dimensional (3D) visualization. Here, we performed 3D electron tomography to compare the ultrastructural changes in the vacuole during infection with different viruses. The 3D models revealed that vacuoles are remodeled in cells infected with cucumber mosaic virus (CMV) or tobacco necrosis virus A Chinese isolate (TNV-AC ), resulting in the formation of spherules at the periphery of the vacuole. These spherules contain neck-like channels that connect their interior with the cytosol. Confocal microscopy of CMV replication proteins 1a and 2a and TNV-AC auxiliary replication protein p23 showed that all of these proteins localize to the tonoplast. Electron microscopy revealed that the expression of these replication proteins alone is sufficient to induce spherule formation on the tonoplast, suggesting that these proteins play prominent roles in inducing vacuolar membrane remodeling. This is the first report of the 3D structures of viral replication factories built on the tonoplasts. These findings contribute to our understanding of vacuole biogenesis under normal conditions and during assembly of plant (+) RNA virus replication complexes.
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Affiliation(s)
- Xueting Wang
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Juncai Ma
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Xuejiao Jin
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Ning Yue
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Peng Gao
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Keith Ka Ki Mai
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Xian-Bing Wang
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Dawei Li
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Byung-Ho Kang
- State Key Laboratory of Agro-Biotechnology, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Yongliang Zhang
- State Key Laboratory of Agro-Biotechnology and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
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6
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Foong SL, Paek KH. Capsicum annum Hsp26.5 promotes defense responses against RNA viruses via ATAF2 but is hijacked as a chaperone for tobamovirus movement protein. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:6142-6158. [PMID: 32640023 DOI: 10.1093/jxb/eraa320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 07/04/2020] [Indexed: 06/11/2023]
Abstract
The expression of Capsicum annuum HEAT SHOCK PROTEIN 26.5 (CaHsp26.5) was triggered by the inoculation of Tobacco mosaic virus pathotype P0 (TMV-P0) but its function in the defense response of plants is unknown. We used gene silencing and overexpression approaches to investigate the effect of CaHsp26.5 expression on different plant RNA viruses. Moreover, we performed protein-protein and protein-RNA interaction assays to study the mechanism of CaHsp26.5 function. CaHsp26.5 binding to a short poly-cytosine motif in the 3'-untranslated region of the genome of some viruses triggers the expression of several defense-related genes such as PATHOGENESIS-RELATED GENE 1 with the help of a transcription factor, NAC DOMAIN-CONTAINING PROTEIN 81 (ATAF2). Thus, an elevated CaHsp26.5 level was accompanied by increased plant resistance against plant viruses such as Cucumber mosaic virus strain Korea. However, the movement proteins of Pepper mild mottle virus pathotype P1,2,3 and TMV-P0 were shown to be able to interact with CaHsp26.5 to maintain the integrity of their proteins. Our work shows CaHsp26.5 as a positive player in the plant defense response against several plant RNA viruses. However, some tobamoviruses can hijack CaHsp26.5's chaperone activity for their own benefit.
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Affiliation(s)
- Siew-Liang Foong
- Department of Life Sciences, Korea University, Seoul, Republic of Korea
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Joshna CR, Saha P, Atugala D, Chua G, Muench DG. Plant PUF RNA-binding proteins: A wealth of diversity for post-transcriptional gene regulation. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 297:110505. [PMID: 32563454 DOI: 10.1016/j.plantsci.2020.110505] [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: 12/15/2019] [Revised: 03/30/2020] [Accepted: 04/19/2020] [Indexed: 06/11/2023]
Abstract
PUF proteins are a conserved group of sequence-specific RNA-binding proteins that typically function to negatively regulate mRNA stability and translation. PUFs are well characterized at the molecular, structural and functional levels in Drosophila, Caenorhabditis elegans, budding yeast and human systems. Although usually encoded by small gene families, PUFs are over-represented in the plant genome, with up to 36 genes identified in a single species. PUF gene expansion in plants has resulted in extensive variability in gene expression patterns, diversity in predicted RNA-binding domain structure, and novel combinations of key amino acids involved in modular nucleotide binding. Reports on the characterization of plant PUF structure and function continue to expand, and include RNA target identification, subcellular distribution, crystal structure, and molecular mechanisms. Arabidopsis PUF mutant analysis has provided insight into biological function, and has identified roles related to development and environmental stress tolerance. The diversity of plant PUFs implies an extensive role for this family of proteins in post-transcriptional gene regulation. This diversity also holds the potential for providing novel RNA-binding domains that could be engineered to produce designer PUFs to alter the metabolism of target RNAs in the cell.
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Affiliation(s)
- Chris R Joshna
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N1N4, Canada
| | - Pritha Saha
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N1N4, Canada
| | - Dilini Atugala
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N1N4, Canada
| | - Gordon Chua
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N1N4, Canada
| | - Douglas G Muench
- Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N1N4, Canada.
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Huang YP, Huang YW, Hsiao YJ, Li SC, Hsu YH, Tsai CH. Autophagy is involved in assisting the replication of Bamboo mosaic virus in Nicotiana benthamiana. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:4657-4670. [PMID: 31552430 PMCID: PMC6760330 DOI: 10.1093/jxb/erz244] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Indexed: 05/20/2023]
Abstract
Autophagy plays a critical role in plants under biotic stress, including the response to pathogen infection. We investigated whether autophagy-related genes (ATGs) are involved in infection with Bamboo mosaic virus (BaMV), a single-stranded positive-sense RNA virus. Initially, we observed that BaMV infection in Nicotiana benthamiana leaves upregulated the expression of ATGs but did not trigger cell death. The induction of ATGs, which possibly triggers autophagy, increased rather than diminished BaMV accumulation in the leaves, as revealed by gene knockdown and transient expression experiments. Furthermore, the inhibitor 3-methyladenine blocked autophagosome formation and the autophagy inducer rapamycin, which negatively and positively affected BaMV accumulation, respectively. Pull-down experiments with an antibody against orange fluorescent protein (OFP)-NbATG8f, an autophagosome marker protein, showed that both plus- and minus-sense BaMV RNAs could associate with NbATG8f. Confocal microscopy revealed that ATG8f-enriched vesicles possibly derived from chloroplasts contained both the BaMV viral RNA and its replicase. Thus, BaMV infection may induce the expression of ATGs possibly via autophagy to selectively engulf a portion of viral RNA-containing chloroplast. Virus-induced vesicles enriched with ATG8f could provide an alternative site for viral RNA replication or a shelter from the host silencing mechanism.
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Affiliation(s)
- Ying-Ping Huang
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Ying-Wen Huang
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Yung-Jen Hsiao
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Siou-Cen Li
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Yau-Huei Hsu
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Ching-Hsiu Tsai
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan
- Advanced Plant Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
- Research Center for Sustainable Energy and Nanotechnology, National Chung Hsing University, Taichung, Taiwan
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Salánki K, Gellért Á, Nemes K, Divéki Z, Balázs E. Molecular Modeling for Better Understanding of Cucumovirus Pathology. Adv Virus Res 2018; 102:59-88. [PMID: 30266176 DOI: 10.1016/bs.aivir.2018.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Cucumber mosaic virus (CMV) is a small RNA virus capable of infecting a wide variety of plant species. The high economic losses due to the CMV infection made this virus a relevant subject of scientific studies, which were further facilitated by the small size of the viral genome. Hence, CMV also became a model organism to investigate the molecular mechanism of pathogenesis. All viral functions are dependent on intra- and intermolecular interactions between nucleic acids and proteins of the virus and the host. This review summarizes the recent data on molecular determinants of such interactions. A particular emphasis is given to the results obtained by utilizing molecular-based planning and modeling techniques.
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Affiliation(s)
- Katalin Salánki
- MTA ATK, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Ákos Gellért
- MTA ATK, Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Katalin Nemes
- MTA ATK, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Zoltán Divéki
- MTA ATK, Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Ervin Balázs
- MTA ATK, Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary.
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Glingston RS, Deb R, Kumar S, Nagotu S. Organelle dynamics and viral infections: at cross roads. Microbes Infect 2018; 21:20-32. [PMID: 29953921 PMCID: PMC7110583 DOI: 10.1016/j.micinf.2018.06.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 01/12/2023]
Abstract
Viruses are obligate intracellular parasites of the host cells. A commonly accepted view is the requirement of internal membranous structures for various aspects of viral life cycle. Organelles enable favourable intracellular environment for several viruses. However, studies reporting organelle dynamics upon viral infections are scant. In this review, we aim to summarize and highlight modulations caused to various organelles upon viral infection or expression of its proteins.
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Affiliation(s)
- R Sahaya Glingston
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Rachayeeta Deb
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Sachin Kumar
- Viral Immunology Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| | - Shirisha Nagotu
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
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Bhattacharyya D, Chakraborty S. Chloroplast: the Trojan horse in plant-virus interaction. MOLECULAR PLANT PATHOLOGY 2018; 19:504-518. [PMID: 28056496 PMCID: PMC6638057 DOI: 10.1111/mpp.12533] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 05/14/2023]
Abstract
The chloroplast is one of the most dynamic organelles of a plant cell. It carries out photosynthesis, synthesizes major phytohormones, plays an active part in the defence response and is crucial for interorganelle signalling. Viruses, on the other hand, are extremely strategic in manipulating the internal environment of the host cell. The chloroplast, a prime target for viruses, undergoes enormous structural and functional damage during viral infection. Indeed, large proportions of affected gene products in a virus-infected plant are closely associated with the chloroplast and the process of photosynthesis. Although the chloroplast is deficient in gene silencing machinery, it elicits the effector-triggered immune response against viral pathogens. Virus infection induces the organelle to produce an extensive network of stromules which are involved in both viral propagation and antiviral defence. From studies over the last few decades, the involvement of the chloroplast in the regulation of plant-virus interaction has become increasingly evident. This review presents an exhaustive account of these facts, with their implications for pathogenicity. We have attempted to highlight the intricacies of chloroplast-virus interactions and to explain the existing gaps in our current knowledge, which will enable virologists to utilize chloroplast genome-based antiviral resistance in economically important crops.
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Affiliation(s)
- Dhriti Bhattacharyya
- Molecular Virology Laboratory, School of Life SciencesJawaharlal Nehru UniversityNew Delhi110 067India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life SciencesJawaharlal Nehru UniversityNew Delhi110 067India
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Poque S, Wu HW, Huang CH, Cheng HW, Hu WC, Yang JY, Wang D, Yeh SD. Potyviral Gene-Silencing Suppressor HCPro Interacts with Salicylic Acid (SA)-Binding Protein 3 to Weaken SA-Mediated Defense Responses. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2018; 31:86-100. [PMID: 29090655 DOI: 10.1094/mpmi-06-17-0128-fi] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The viral infection process is a battle between host defense response and pathogen antagonizing action. Several studies have established a tight link between the viral RNA silencing suppressor (RSS) and the repression of salicylic acid (SA)-mediated defense responses, nonetheless host factors directly linking an RSS and the SA pathway remains unidentified. From yeast two-hybrid analysis, we identified an interaction between the potyviral RSS helper-component proteinase (HCPro) and SA-binding protein SABP3. Co-localization and bimolecular fluorescence complementation analyses validated the direct in vivo interaction between Turnip mosaic virus (TuMV) HCPro and the Arabidopsis homologue of SABP3, AtCA1. Additionally, transient expression of TuMV HCPro demonstrated its ability to act as a negative regulator of AtCA1. When the plants of the AtCA1 knockout mutant line were inoculated with TuMV, our results indicated that AtCA1 is essential to restrict viral spreading and accumulation, induce SA accumulation, and trigger the SA pathway. Unexpectedly, the AtCA1 overexpression line also displayed a similar phenotype, suggesting that the constitutive expression of AtCA1 antagonizes the SA pathway. Taken together, our results depict AtCA1 as an essential regulator of SA defense responses. Moreover, the interaction of potyviral HCPro with this regulator compromises the SA pathway to weaken host defense responses and facilitate viral infection.
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Affiliation(s)
- Sylvain Poque
- 1 Department of Plant Pathology, National Chung-Hsing University, Taichung City 40227, Taiwan, R.O.C
| | - Hui-Wen Wu
- 2 Agricultural Biotechnology Center, National Chung-Hsing University
| | - Chung-Hao Huang
- 1 Department of Plant Pathology, National Chung-Hsing University, Taichung City 40227, Taiwan, R.O.C
| | - Hao-Wen Cheng
- 3 NCHU-UCD Plant and Food Biotechnology Center, National Chung-Hsing University
| | - Wen-Chi Hu
- 3 NCHU-UCD Plant and Food Biotechnology Center, National Chung-Hsing University
| | - Jun-Yi Yang
- 4 Institute of Biochemistry, National Chung-Hsing University; and
| | - David Wang
- 5 Department of Forestry, National Chung-Hsing University
| | - Shyi-Dong Yeh
- 1 Department of Plant Pathology, National Chung-Hsing University, Taichung City 40227, Taiwan, R.O.C
- 2 Agricultural Biotechnology Center, National Chung-Hsing University
- 3 NCHU-UCD Plant and Food Biotechnology Center, National Chung-Hsing University
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13
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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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14
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Zhao J, Zhang X, Hong Y, Liu Y. Chloroplast in Plant-Virus Interaction. Front Microbiol 2016; 7:1565. [PMID: 27757106 PMCID: PMC5047884 DOI: 10.3389/fmicb.2016.01565] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 09/20/2016] [Indexed: 11/16/2022] Open
Abstract
In plants, the chloroplast is the organelle that conducts photosynthesis. It has been known that chloroplast is involved in virus infection of plants for approximate 70 years. Recently, the subject of chloroplast-virus interplay is getting more and more attention. In this article we discuss the different aspects of chloroplast-virus interaction into three sections: the effect of virus infection on the structure and function of chloroplast, the role of chloroplast in virus infection cycle, and the function of chloroplast in host defense against viruses. In particular, we focus on the characterization of chloroplast protein-viral protein interactions that underlie the interplay between chloroplast and virus. It can be summarized that chloroplast is a common target of plant viruses for viral pathogenesis or propagation; and conversely, chloroplast and its components also can play active roles in plant defense against viruses. Chloroplast photosynthesis-related genes/proteins (CPRGs/CPRPs) are suggested to play a central role during the complex chloroplast-virus interaction.
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Affiliation(s)
- Jinping Zhao
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua UniversityBeijing, China
- State Key Laboratory Breeding Base for Sustainable Control of Pest and Disease, Key Laboratory of Biotechnology in Plant Protection, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural SciencesHangzhou, China
| | - Xian Zhang
- Research Centre for Plant RNA Signaling, School of Life and Environmental Sciences, Hangzhou Normal UniversityHangzhou, China
| | - Yiguo Hong
- Research Centre for Plant RNA Signaling, School of Life and Environmental Sciences, Hangzhou Normal UniversityHangzhou, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua UniversityBeijing, China
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15
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Isolation and Characterization of Pepper Genes Interacting with the CMV-P1 Helicase Domain. PLoS One 2016; 11:e0146320. [PMID: 26751216 PMCID: PMC4709182 DOI: 10.1371/journal.pone.0146320] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 12/14/2015] [Indexed: 01/04/2023] Open
Abstract
Cucumber mosaic virus (CMV) is a destructive pathogen affecting Capsicum annuum (pepper) production. The pepper Cmr1 gene confers resistance to most CMV strains, but is overcome by CMV-P1 in a process dependent on the CMV-P1 RNA1 helicase domain (P1 helicase). Here, to identify host factors involved in CMV-P1 infection in pepper, a yeast two-hybrid library derived from a C. annuum ‘Bukang’ cDNA library was screened, producing a total of 76 potential clones interacting with the P1 helicase. Beta-galactosidase filter lift assay, PCR screening, and sequencing analysis narrowed the candidates to 10 genes putatively involved in virus infection. The candidate host genes were silenced in Nicotiana benthamiana plants that were then inoculated with CMV-P1 tagged with the green fluorescent protein (GFP). Plants silenced for seven of the genes showed development comparable to N. benthamiana wild type, whereas plants silenced for the other three genes showed developmental defects including stunting and severe distortion. Silencing formate dehydrogenase and calreticulin-3 precursor led to reduced virus accumulation. Formate dehydrogenase-silenced plants showed local infection in inoculated leaves, but not in upper (systemic) leaves. In the calreticulin-3 precursor-silenced plants, infection was not observed in either the inoculated or the upper leaves. Our results demonstrate that formate dehydrogenase and calreticulin-3 precursor are required for CMV-P1 infection.
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16
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Abstract
In plants, the chloroplast is the organelle that conducts photosynthesis. It has been known that chloroplast is involved in virus infection of plants for approximate 70 years. Recently, the subject of chloroplast-virus interplay is getting more and more attention. In this article we discuss the different aspects of chloroplast-virus interaction into three sections: the effect of virus infection on the structure and function of chloroplast, the role of chloroplast in virus infection cycle, and the function of chloroplast in host defense against viruses. In particular, we focus on the characterization of chloroplast protein-viral protein interactions that underlie the interplay between chloroplast and virus. It can be summarized that chloroplast is a common target of plant viruses for viral pathogenesis or propagation; and conversely, chloroplast and its components also can play active roles in plant defense against viruses. Chloroplast photosynthesis-related genes/proteins (CPRGs/CPRPs) are suggested to play a central role during the complex chloroplast-virus interaction.
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Affiliation(s)
- Jinping Zhao
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua UniversityBeijing, China; State Key Laboratory Breeding Base for Sustainable Control of Pest and Disease, Key Laboratory of Biotechnology in Plant Protection, Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural SciencesHangzhou, China
| | - Xian Zhang
- Research Centre for Plant RNA Signaling, School of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China
| | - Yiguo Hong
- Research Centre for Plant RNA Signaling, School of Life and Environmental Sciences, Hangzhou Normal University Hangzhou, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University Beijing, China
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Li J, Xue J, Zhang HM, Yang J, Lv MF, Xie L, Meng Y, Li PP, Chen JP. Interactions between the P6 and P5-1 proteins of southern rice black-streaked dwarf fijivirus in yeast and plant cells. Arch Virol 2013; 158:1649-59. [PMID: 23474918 DOI: 10.1007/s00705-013-1660-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 01/13/2013] [Indexed: 11/26/2022]
Abstract
Southern rice black-streaked dwarf virus (SRBSDV) is a recently described member of the genus Fijivirus, family Reoviridae. The roles of the proteins encoded by the SRBSDV genome have rarely been studied. In a yeast two-hybrid (YTH) assay in which SRBSDV P6, a putatively multifunctional protein, was used as bait and an SRBSDV cDNA library was used as prey, there was a strong interaction between the P6 and P5-1 proteins. The interaction was confirmed by bimolecular fluorescence complement (BiFC) assay in plant cells. YTH analysis using truncated mutants showed that the N-terminal region (amino acids 9-231) of P5-1 is necessary for binding P5-1 to P6 and that the N-terminal fragment (amino acids 1-93) of P6 is necessary for its interaction with P5-1. SRBSDV P5-1 formed granules positioned at the cell periphery in Nicotiana benthamiana leaves; P6 was present in both the cytoplasm and the nucleus and formed punctate bodies associated with the cell periphery. Immunogold labeling showed that both P6 and P5-1 localized within viroplasms in infected cells of rice plants. These results suggest that the interaction between P5-1 and P6 of SRBSDV may be involved in the formation of viroplasms.
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Affiliation(s)
- Jing Li
- State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Key Laboratory of Plant Protection and Biotechnology, Ministry of Agriculture, China
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Un Huh S, Paek KH. Role of Arabidopsis Pumilio RNA binding protein 5 in virus infection. PLANT SIGNALING & BEHAVIOR 2013; 8:e23975. [PMID: 23511198 PMCID: PMC3906142 DOI: 10.4161/psb.23975] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Regulation of gene expression is mediated by diverse RNA binding proteins which play important roles in development and defense processes. Pumilio/FBF (Puf) protein in mammals functions as a posttranscriptional/translational repressor by binding to the 3' UTR regions of its target mRNAs. Previous study reported that APUM5 provides protection against CMV infection by directly binding to CMV RNAs in Arabidopsis. CMV RNAs contain putative Pumilio-binding motifs and APUM5 bound to the 3' UTR and some of its internal motifs both in vitro and in vivo. APUM5 works as a negative regulator of the 3' UTR of CMV and it might regulate CMV replication. Our findings suggest that APUM5 acts as a defensive repressor in plants during CMV infection. However, functions of APUM5 and other APUM members are still not clear and more studies are needed to find out the interacting partners and target mRNAs in host plant.
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Hu Z, Zhang T, Yao M, Feng Z, Miriam K, Wu J, Zhou X, Tao X. The 2a protein of Cucumber mosaic virus induces a hypersensitive response in cowpea independently of its replicase activity. Virus Res 2012; 170:169-73. [PMID: 23079112 DOI: 10.1016/j.virusres.2012.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 10/04/2012] [Accepted: 10/06/2012] [Indexed: 10/27/2022]
Abstract
Resistance in cowpea to infection with strains of Cucumber mosaic virus (CMV) involves a local hypersensitive response (HR), and previous studies indicated that the 2a replicase of CMV is involved in HR induction. In this study, we confirmed and extended this observation by demonstrating that the nonviral expression of the 2a protein encoded by CMV is able to induce a cell death response in cowpea plants, whereas no other CMV-encoded proteins elicits such response. The 2a single-amino acid mutant, F631Y, no longer induces the necrosis response, yet the A641S mutant still induces cell death. The 2a double mutant, F631Y and A641S, does not induce HR. However, the three 2a mutants have comparable replicase activities in a fluorescence reporter assay. The 2a(D610A) mutant that alters the highly conserved GDD motif abolishes the replicase activity, however it does not affect HR induction in cowpea. The 2a(301-778aa) fragment introduced with the same D610A mutation in the GDD motif is also capable of inducing HR in cowpea. Collectively, these findings suggest that the 2a protein of CMV is sufficient to induce HR in cowpea independently of its replicase activity.
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Affiliation(s)
- Zhongze Hu
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
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Abstract
Cucumber mosaic virus (CMV) is an important virus because of its agricultural impact in the Mediterranean Basin and worldwide, and also as a model for understanding plant-virus interactions. This review focuses on those areas where most progress has been made over the past decade in our understanding of CMV. Clearly, a deep understanding of the role of the recently described CMV 2b gene in suppression of host RNA silencing and viral virulence is the most important discovery. These findings have had an impact well beyond the virus itself, as the 2b gene is an important tool in the studies of eukaryotic gene regulation. Protein 2b was shown to be involved in most of the steps of the virus cycle and to interfere with several basal host defenses. Progress has also been made concerning the mechanisms of virus replication and movement. However, only a few host proteins that interact with viral proteins have been identified, making this an area of research where major efforts are still needed. Another area where major advances have been made is CMV population genetics, where contrasting results were obtained. On the one hand, CMV was shown to be prone to recombination and to show high genetic diversity based on sequence data of different isolates. On the other hand, populations did not exhibit high genetic variability either within plants, or even in a field and the nearby wild plants. The situation was partially clarified with the finding that severe bottlenecks occur during both virus movement within a plant and transmission between plants. Finally, novel studies were undertaken to elucidate mechanisms leading to selection in virus population, according to the host or its environment, opening a new research area in plant-virus coevolution.
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Huh SU, Kim KJ, Paek KH. Capsicum annuum basic transcription factor 3 (CaBtf3) regulates transcription of pathogenesis-related genes during hypersensitive response upon Tobacco mosaic virus infection. Biochem Biophys Res Commun 2011; 417:910-7. [PMID: 22209846 DOI: 10.1016/j.bbrc.2011.12.074] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 12/15/2011] [Indexed: 10/14/2022]
Abstract
Hypersensitive response (HR) cell death upon plant virus infection is an excellent plant strategy for inhibiting viral movement and obtaining systemic acquired resistance (SAR) against further infection. Various host factors are involved in these HR processes, either directly as viral resistance proteins or indirectly. We characterized a gene encoding the CaBtf3 [β-nascent polypeptide-associated complex (NAC) subunit] of NAC from the hot pepper plant. NAC contacts nascent polypeptides to prevent aggregation and degradation of newly synthesized proteins by controlling cotranslational protein folding. CaBtf3 protein fused to green fluorescent protein predominantly localized to the nucleus. Silencing phenotype of CaBtf3 upon the Tobacco mosaic virus (TMV)-P(0) inoculation exhibited reduced HR cell death and decreased expression of some HR-associated genes, but increased TMV coat protein levels compared with TRV2 control plants. Furthermore, silencing of NbBtf3, a highly homologous gene of CaBtf3, also led to the reduced Bax- and Pto-mediated cell death. The results indicate that CaBtf3 might be involved in HR cell death and could function as a transcription factor in the nucleus by transcriptional regulation of HR-related gene expression.
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Affiliation(s)
- Sung Un Huh
- School of Life Sciences and Biotechnology, Korea University, 1, 5-ga, Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea
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