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Chen Y, Jia M, Ge L, Li Z, He H, Zhou X, Li F. A Negative Feedback Loop Compromises NMD-Mediated Virus Restriction by the Autophagy Pathway in Plants. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400978. [PMID: 39189522 PMCID: PMC11348178 DOI: 10.1002/advs.202400978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 05/21/2024] [Indexed: 08/28/2024]
Abstract
Nonsense-mediated decay (NMD) and autophagy play pivotal roles in restricting virus infection in plants. However, the interconnection between these two pathways in viral infections has not been explored. Here, it is shown that overexpression of NbSMG7 and NbUPF3 attenuates cucumber green mottle mosaic virus (CGMMV) infection by recognizing the viral internal termination codon and vice versa. NbSMG7 is subjected to autophagic degradation, which is executed by its interaction with one of the autophagy-related proteins, NbATG8i. Mutation of the ATG8 interacting motif (AIM) in NbSMG7 (SMG7mAIM1) abolishes the interaction and comprises its autophagic degradation. Silencing of NbSMG7 and NbATG8i, or NbUPF3 and NbATG8i, compared to silencing each gene individually, leads to more virus accumulations, but overexpression of NbSMG7 and NbATG8i fails to achieve more potent virus inhibition. When CGMMV is co-inoculated with NbSMG7mAIM1 or with NbUPF3, compared to co-inoculating with NbSMG7 in NbATG8i transgene plants, the inoculated plants exhibit milder viral phenotypes. These findings reveal that NMD-mediated virus inhibition is impaired by the autophagic degradation of SMG7 in a negative feedback loop, and a novel regulatory interplay between NMD and autophagy is uncovered, providing insights that are valuable in optimizing strategies to harness NMD and autophagy for combating viral infections.
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Affiliation(s)
- Yalin Chen
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Mingxuan Jia
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Linhao Ge
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Zhaolei Li
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Hao He
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
- State Key Laboratory of Rice BiologyInstitute of BiotechnologyZhejiang UniversityHangzhouZhejiang310058China
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect PestsInstitute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing100193China
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Wang L, Shi W, Aziz A, Wang X, Liu H, Shen W, Cui H, Dai Z. Mutating the arginine residue within the FRNK motif of telosma mosaic virus (TelMV) HC-Pro protein attenuates viral infection and confers effective protection against TelMV in passion fruit (Passiflora edulis). PEST MANAGEMENT SCIENCE 2024. [PMID: 38895838 DOI: 10.1002/ps.8252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 05/23/2024] [Accepted: 06/04/2024] [Indexed: 06/21/2024]
Abstract
BACKGROUND Telosma mosaic virus (TelMV, Potyvirus, Potyviridae) is an emerging viral pathogen that threatens passion fruit plantations worldwide. However, an efficient strategy for controlling such a virus is not yet available. Cross protection is a phenomenon in which pre-infection of a plant with one mild strain prevents or delays subsequent infection by the same or closely related virus. HC-Pro is the potyviral encoded multifunctional protein involved in several steps of viral infection, including multiplication, movement, transmission and RNA silencing suppression. In this study, we tested whether it is possible to generate attenuated viral strains capable of conferring protection against severe TelMV infection by manipulating the HC-Pro gene. RESULTS By introducing point mutation into the conserved motif FRNK of HC-Pro that is essential for RNA silencing suppression, we have successfully obtained three attenuated mutants of TelMV (R181K, R181D, and R181E, respectively). These attenuated TelMV mutants could systemically infect passion fruit plants without noticeable symptoms. Pre-inoculation of one of these attenuated mutants confers efficient protection against subsequent infection by severe TelMV strain. Moreover, we demonstrated that the HC-Pros harbored by the attenuated mutants exhibit reduced RNA silencing suppression activity in Nicotiana benthamiana leaves. CONCLUSION The attenuated TelMV mutants developed in this study that are suitable for cross protection offer a practical, powerful tool to fight against TelMV for sustainable passion fruit production. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Linxi Wang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Wei Shi
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Asma Aziz
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Xiaoqing Wang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Haobin Liu
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Wentao Shen
- Hainan Key Laboratory for Protection and Utilization of Tropical Bioresources, Institute of Tropical Bioscience and Biotechnology, Sanya Research Institute, Hainan Institute for Tropical Agricultural Resources, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Hongguang Cui
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Zhaoji Dai
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education), School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
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3
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Kamal H, Zafar MM, Razzaq A, Parvaiz A, Ercisli S, Qiao F, Jiang X. Functional role of geminivirus encoded proteins in the host: Past and present. Biotechnol J 2024; 19:e2300736. [PMID: 38900041 DOI: 10.1002/biot.202300736] [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: 12/26/2023] [Revised: 03/19/2024] [Accepted: 04/16/2024] [Indexed: 06/21/2024]
Abstract
During plant-pathogen interaction, plant exhibits a strong defense system utilizing diverse groups of proteins to suppress the infection and subsequent establishment of the pathogen. However, in response, pathogens trigger an anti-silencing mechanism to overcome the host defense machinery. Among plant viruses, geminiviruses are the second largest virus family with a worldwide distribution and continue to be production constraints to food, feed, and fiber crops. These viruses are spread by a diverse group of insects, predominantly by whiteflies, and are characterized by a single-stranded DNA (ssDNA) genome coding for four to eight proteins that facilitate viral infection. The most effective means to managing these viruses is through an integrated disease management strategy that includes virus-resistant cultivars, vector management, and cultural practices. Dynamic changes in this virus family enable the species to manipulate their genome organization to respond to external changes in the environment. Therefore, the evolutionary nature of geminiviruses leads to new and novel approaches for developing virus-resistant cultivars and it is essential to study molecular ecology and evolution of geminiviruses. This review summarizes the multifunctionality of each geminivirus-encoded protein. These protein-based interactions trigger the abrupt changes in the host methyl cycle and signaling pathways that turn over protein normal production and impair the plant antiviral defense system. Studying these geminivirus interactions localized at cytoplasm-nucleus could reveal a more clear picture of host-pathogen relation. Data collected from this antagonistic relationship among geminivirus, vector, and its host, will provide extensive knowledge on their virulence mode and diversity with climate change.
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Affiliation(s)
- Hira Kamal
- Department of Plant Pathology, Washington State University, Pullman, Washington, USA
| | - Muhammad Mubashar Zafar
- Sanya Institute of Breeding and Multiplication, School of Tropical Agriculture and Forestry, Hainan University, Sanya, China
| | - Abdul Razzaq
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Aqsa Parvaiz
- Department of Biochemistry and Biotechnology, The Women University Multan, Multan, Pakistan
| | - Sezai Ercisli
- Department of Horticulture, Faculty of Agriculture, Ataturk University, Erzurum, Turkey
| | - Fei Qiao
- Sanya Institute of Breeding and Multiplication, School of Tropical Agriculture and Forestry, Hainan University, Sanya, China
| | - Xuefei Jiang
- Sanya Institute of Breeding and Multiplication, School of Tropical Agriculture and Forestry, Hainan University, Sanya, China
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Wu J, Zhang Y, Li F, Zhang X, Ye J, Wei T, Li Z, Tao X, Cui F, Wang X, Zhang L, Yan F, Li S, Liu Y, Li D, Zhou X, Li Y. Plant virology in the 21st century in China: Recent advances and future directions. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2024; 66:579-622. [PMID: 37924266 DOI: 10.1111/jipb.13580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/02/2023] [Indexed: 11/06/2023]
Abstract
Plant viruses are a group of intracellular pathogens that persistently threaten global food security. Significant advances in plant virology have been achieved by Chinese scientists over the last 20 years, including basic research and technologies for preventing and controlling plant viral diseases. Here, we review these milestones and advances, including the identification of new crop-infecting viruses, dissection of pathogenic mechanisms of multiple viruses, examination of multilayered interactions among viruses, their host plants, and virus-transmitting arthropod vectors, and in-depth interrogation of plant-encoded resistance and susceptibility determinants. Notably, various plant virus-based vectors have also been successfully developed for gene function studies and target gene expression in plants. We also recommend future plant virology studies in China.
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Affiliation(s)
- Jianguo Wu
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Vector-borne Virus Research Center, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Yongliang Zhang
- State Key Laboratory of Plant Environmental Resilience and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Xiaoming Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian Ye
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Taiyun Wei
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Vector-borne Virus Research Center, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Zhenghe Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Xiaorong Tao
- Department of Plant Pathology, The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing, 210095, China
| | - Feng Cui
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xianbing Wang
- State Key Laboratory of Plant Environmental Resilience and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Lili Zhang
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Fei Yan
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Plant Virology, Ningbo University, Ningbo, 315211, China
| | - Shifang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Dawei Li
- State Key Laboratory of Plant Environmental Resilience and Ministry of Agriculture Key Laboratory of Soil Microbiology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Yi Li
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, Vector-borne Virus Research Center, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China
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Qin L, Liu H, Liu P, Jiang L, Cheng X, Li F, Shen W, Qiu W, Dai Z, Cui H. Rubisco small subunit (RbCS) is co-opted by potyvirids as the scaffold protein in assembling a complex for viral intercellular movement. PLoS Pathog 2024; 20:e1012064. [PMID: 38437247 PMCID: PMC10939294 DOI: 10.1371/journal.ppat.1012064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 03/14/2024] [Accepted: 02/21/2024] [Indexed: 03/06/2024] Open
Abstract
Plant viruses must move through plasmodesmata (PD) to complete their life cycles. For viruses in the Potyviridae family (potyvirids), three viral factors (P3N-PIPO, CI, and CP) and few host proteins are known to participate in this event. Nevertheless, not all the proteins engaging in the cell-to-cell movement of potyvirids have been discovered. Here, we found that HCPro2 encoded by areca palm necrotic ring spot virus (ANRSV) assists viral intercellular movement, which could be functionally complemented by its counterpart HCPro from a potyvirus. Affinity purification and mass spectrometry identified several viral factors (including CI and CP) and host proteins that are physically associated with HCPro2. We demonstrated that HCPro2 interacts with both CI and CP in planta in forming PD-localized complexes during viral infection. Further, we screened HCPro2-associating host proteins, and identified a common host protein in Nicotiana benthamiana-Rubisco small subunit (NbRbCS) that mediates the interactions of HCPro2 with CI or CP, and CI with CP. Knockdown of NbRbCS impairs these interactions, and significantly attenuates the intercellular and systemic movement of ANRSV and three other potyvirids (turnip mosaic virus, pepper veinal mottle virus, and telosma mosaic virus). This study indicates that a nucleus-encoded chloroplast-targeted protein is hijacked by potyvirids as the scaffold protein to assemble a complex to facilitate viral movement across cells.
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Affiliation(s)
- Li Qin
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Hongjun Liu
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Peilan Liu
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Lu Jiang
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaofei Cheng
- College of Plant Protection/Key Laboratory of Germplasm Enhancement, Physiology and Ecology of Food Crops in Cold Region of Chinese Education Ministry, Northeast Agricultural University, Harbin, China
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wentao Shen
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Wenping Qiu
- Center for Grapevine Biotechnology, William H. Darr College of Agriculture, Missouri State University, Mountain Grove, United States of America
| | - Zhaoji Dai
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Hongguang Cui
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and School of Tropical Agriculture and Forestry, Hainan University, Haikou, China
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Zvereva AS, Klingenbrunner M, Teige M. Calcium signaling: an emerging player in plant antiviral defense. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:1265-1273. [PMID: 37940194 PMCID: PMC10901205 DOI: 10.1093/jxb/erad442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 11/03/2023] [Indexed: 11/10/2023]
Abstract
Calcium is a universal messenger in different kingdoms of living organisms and regulates most physiological processes, including defense against pathogens. The threat of viral infections in humans has become very clear in recent years, and this has triggered detailed research into all aspects of host-virus interactions, including the suppression of calcium signaling in infected cells. At the same time, however, the threat of plant viral infections is underestimated in society, and research in the field of calcium signaling during plant viral infections is scarce. Here we highlight an emerging role of calcium signaling for antiviral protection in plants, in parallel with the known evidence from studies of animal cells. Obtaining more knowledge in this domain might open up new perspectives for future crop protection and the improvement of food security.
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Affiliation(s)
- Anna S Zvereva
- Department of Functional & Evolutionary Ecology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Michael Klingenbrunner
- Department of Functional & Evolutionary Ecology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Markus Teige
- Department of Functional & Evolutionary Ecology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
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Xu X, Lou Y, Liang K, Liu J, Wang Z, Chen B, Li W. The P2 nucleic acid binding protein of Sugarcane bacilliform virus is a viral pathogenic factor. PeerJ 2024; 12:e16982. [PMID: 38406282 PMCID: PMC10885806 DOI: 10.7717/peerj.16982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 01/30/2024] [Indexed: 02/27/2024] Open
Abstract
Background Saccharum spp. is the primary source of sugar and plays a significant role in global renewable bioenergy. Sugarcane bacilliform virus (SCBV) is one of the most important viruses infecting sugarcane, causing severe yield losses and quality degradation. It is of great significance to reveal the pathogenesis of SCBV and resistance breeding. However, little is known about the viral virulence factors or RNA silencing suppressors and the molecular mechanism of pathogenesis. Methods To systematically investigate the functions of the unknown protein P2 encoded by SCBV ORF2. Phylogenetic analysis was implemented to infer the evolutionary relationship between the P2 of SCBV and other badnaviruses. The precise subcellular localization of P2 was verified in the transient infiltrated Nicotiana benthamiana epidermal mesophyll cells and protoplasts using the Laser scanning confocal microscope (LSCM). The post-transcriptional gene silencing (PTGS) and transcriptional gene silencing (TGS) RNA silencing suppressor activity of P2 was analyzed, respectively. Furthermore, restriction digestion and RT-qPCR assays were conducted to verify the probable mechanism of P2 on repressing DNA methylation. To explore the pathogenicity of P2, a potato virus X-based viral vector was used to heterologously express SCBV P2 and the consequent H2O2 accumulation was detected by the 3,3'-diaminobenzidine (DAB) staining method. Results Phylogenetic analysis shows that SCBV has no obvious sequence similarity and low genetic relatedness to Badnavirus and Tungrovirus representatives. LSCM studies show that P2 is localized in both the cytoplasm and nucleus. Moreover, P2 is shown to be a suppressor of PTGS and TGS, which can not only repress ssRNA-induced gene silencing but also disrupt the host RNA-directed DNA methylation (RdDM) pathway. In addition, P2 can trigger an oxidative burst and cause typical hypersensitive-like response (HLR) necrosis in systemic leaves of N. benthamiana when expressed by PVX. Overall, our results laid a foundation for deciphering the molecular mechanism of SCBV pathogenesis and made progress for resistance breeding.
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Affiliation(s)
- Xiongbiao Xu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi key Laboratory of Sugarcane biology, Province and Ministry Co-sponsored Collaborative Innovation Center of Canesugar Industry, College of Agriculture, Guangxi University, Nanning, Guangxi, China
| | - Yinian Lou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi key Laboratory of Sugarcane biology, Province and Ministry Co-sponsored Collaborative Innovation Center of Canesugar Industry, College of Agriculture, Guangxi University, Nanning, Guangxi, China
| | - Kaili Liang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi key Laboratory of Sugarcane biology, Province and Ministry Co-sponsored Collaborative Innovation Center of Canesugar Industry, College of Agriculture, Guangxi University, Nanning, Guangxi, China
| | - Jingying Liu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi key Laboratory of Sugarcane biology, Province and Ministry Co-sponsored Collaborative Innovation Center of Canesugar Industry, College of Agriculture, Guangxi University, Nanning, Guangxi, China
| | - Zhiyuan Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi key Laboratory of Sugarcane biology, Province and Ministry Co-sponsored Collaborative Innovation Center of Canesugar Industry, College of Agriculture, Guangxi University, Nanning, Guangxi, China
| | - Baoshan Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi key Laboratory of Sugarcane biology, Province and Ministry Co-sponsored Collaborative Innovation Center of Canesugar Industry, College of Agriculture, Guangxi University, Nanning, Guangxi, China
| | - Wenlan Li
- College of Life Science and Technology, Guangxi University, Nanning, Guangxi, China
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Li Q, Liu Y, Zhang X. Biomolecular condensates in plant RNA silencing: insights into formation, function, and stress responses. THE PLANT CELL 2024; 36:227-245. [PMID: 37772963 PMCID: PMC10827315 DOI: 10.1093/plcell/koad254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/14/2023] [Accepted: 09/14/2023] [Indexed: 09/30/2023]
Abstract
Biomolecular condensates are dynamic structures formed through diverse mechanisms, including liquid-liquid phase separation. These condensates have emerged as crucial regulators of cellular processes in eukaryotic cells, enabling the compartmentalization of specific biological reactions while allowing for dynamic exchange of molecules with the surrounding environment. RNA silencing, a conserved gene regulatory mechanism mediated by small RNAs (sRNAs), plays pivotal roles in various biological processes. Multiple types of biomolecular condensate, including dicing bodies, processing bodies, small interfering RNA bodies, and Cajal bodies, have been identified as key players in RNA silencing pathways. These biomolecular condensates provide spatial compartmentation for the biogenesis, loading, action, and turnover of small RNAs. Moreover, they actively respond to stresses, such as viral infections, and modulate RNA silencing activities during stress responses. This review summarizes recent advances in understanding of dicing bodies and other biomolecular condensates involved in RNA silencing. We explore their formation, roles in RNA silencing, and contributions to antiviral resistance responses. This comprehensive overview provides insights into the functional significance of biomolecular condensates in RNA silencing and expands our understanding of their roles in gene expression and stress responses in plants.
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Affiliation(s)
- Qi Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Yang Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoming Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- HainanYazhou Bay Seed Lab, Sanya, China
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9
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Zhang X, Wang D, Zhao P, Sun Y, Fang RX, Ye J. Near-infrared light and PIF4 promote plant antiviral defense by enhancing RNA interference. PLANT COMMUNICATIONS 2024; 5:100644. [PMID: 37393430 PMCID: PMC10811336 DOI: 10.1016/j.xplc.2023.100644] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/13/2023] [Accepted: 06/27/2023] [Indexed: 07/03/2023]
Abstract
The molecular mechanism underlying phototherapy and light treatment, which utilize various wavelength spectra of light, including near-infrared (NIR), to cure human and plant diseases, is obscure. Here we revealed that NIR light confers antiviral immunity by positively regulating PHYTOCHROME-INTERACTING FACTOR 4 (PIF4)-activated RNA interference (RNAi) in plants. PIF4, a central transcription factor involved in light signaling, accumulates to high levels under NIR light in plants. PIF4 directly induces the transcription of two essential components of RNAi, RNA-DEPENDENT RNA POLYMERASE 6 (RDR6) and ARGONAUTE 1 (AGO1), which play important roles in resistance to both DNA and RNA viruses. Moreover, the pathogenic determinant βC1 protein, which is evolutionarily conserved and encoded by betasatellites, interacts with PIF4 and inhibits its positive regulation of RNAi by disrupting PIF4 dimerization. These findings shed light on the molecular mechanism of PIF4-mediated plant defense and provide a new perspective for the exploration of NIR antiviral treatment.
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Affiliation(s)
- Xuan Zhang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Duan Wang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pingzhi Zhao
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanwei Sun
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Rong-Xiang Fang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Ye
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing 100049, China.
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10
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Parperides E, El Mounadi K, Garcia‐Ruiz H. Induction and suppression of gene silencing in plants by nonviral microbes. MOLECULAR PLANT PATHOLOGY 2023; 24:1347-1356. [PMID: 37438989 PMCID: PMC10502822 DOI: 10.1111/mpp.13362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/22/2023] [Accepted: 05/23/2023] [Indexed: 07/14/2023]
Abstract
Gene silencing is a conserved mechanism in eukaryotes that dynamically regulates gene expression. In plants, gene silencing is critical for development and for maintenance of genome integrity. Additionally, it is a critical component of antiviral defence in plants, nematodes, insects, and fungi. To overcome gene silencing, viruses encode effectors that suppress gene silencing. A growing body of evidence shows that gene silencing and suppression of silencing are also used by plants during their interaction with nonviral pathogens such as fungi, oomycetes, and bacteria. Plant-pathogen interactions involve trans-kingdom movement of small RNAs into the pathogens to alter the function of genes required for their development and virulence. In turn, plant-associated pathogenic and nonpathogenic microbes also produce small RNAs that move trans-kingdom into host plants to disrupt pathogen defence through silencing of plant genes. The mechanisms by which these small RNAs move from the microbe to the plant remain poorly understood. In this review, we examine the roles of trans-kingdom small RNAs and silencing suppressors produced by nonviral microbes in inducing and suppressing gene silencing in plants. The emerging model is that gene silencing and suppression of silencing play critical roles in the interactions between plants and their associated nonviral microbes.
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Affiliation(s)
- Eric Parperides
- Department of Plant Pathology and Nebraska Center for VirologyUniversity of Nebraska‐LincolnLincolnNebraskaUSA
| | - Kaoutar El Mounadi
- Department of BiologyKutztown University of PennsylvaniaKutztownPennsylvaniaUSA
| | - Hernan Garcia‐Ruiz
- Department of Plant Pathology and Nebraska Center for VirologyUniversity of Nebraska‐LincolnLincolnNebraskaUSA
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11
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Wang Y, Hu T, He Y, Su C, Wang Z, Zhou X. N-terminal acetylation of the βC1 protein encoded by the betasatellite of tomato yellow leaf curl China virus is critical for its viral pathogenicity. Virology 2023; 586:1-11. [PMID: 37473501 DOI: 10.1016/j.virol.2023.07.003] [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: 05/15/2023] [Revised: 06/19/2023] [Accepted: 07/04/2023] [Indexed: 07/22/2023]
Abstract
N-terminal acetylation (N-acetylation) is one of the most common protein modifications and plays crucial roles in viability and stress responses in animals and plants. However, very little is known about N-acetylation of viral proteins. Here, we identified the Thr residue at position 2 (Thr-2) in the βC1 protein encoded by the betasatellite of tomato yellow leaf curl China virus (TYLCCNB-βC1) as a novel N-acetylation site. Furthermore, the effects of TYLCCNB-βC1 N-acetylation on its function as a pathogenicity factor were determined via N-acetylation mutants in Nicotiana benthamiana plants. We found that N-acetylation of TYLCCNB-βC1 is critical for its self-interaction in the nucleus and viral pathogenesis, and that removal of N-acetylation of TYLCCNB-βC1 attenuated tomato yellow leaf curl China virus-induced symptoms and led to accelerated degradation of TYLCCNB-βC1 through the ubiquitin-proteasome system. Our data reveal a protective effect of N-acetylation of TYLCCNB-βC1 on its pathogenesis and demonstrate an antagonistic crosstalk between N-acetylation and ubiquitination in this geminiviral protein.
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Affiliation(s)
- Yaqin Wang
- State Key Laboratory of Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Tao Hu
- State Key Laboratory of Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Yuting He
- State Key Laboratory of Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Chenlu Su
- State Key Laboratory of Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Zhanqi Wang
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, College of Life Sciences, Huzhou University, Huzhou, 313000, China.
| | - Xueping Zhou
- State Key Laboratory of Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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12
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Sharma S, Sett S, Das T, Prasad A, Prasad M. Recent perspective of non-coding RNAs at the nexus of plant-pathogen interaction. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 201:107852. [PMID: 37356385 DOI: 10.1016/j.plaphy.2023.107852] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/06/2023] [Accepted: 06/18/2023] [Indexed: 06/27/2023]
Abstract
In natural habitats, plants are exploited by pathogens in biotrophic or necrotrophic ways. Concurrently, plants have evolved their defense systems for rapid perception of pathogenic effectors and begin concerted cellular reprogramming pathways to confine the pathogens at the entry sites. During the reorganization of cellular signaling mechanisms following pathogen attack, non-coding RNAs serves an indispensable role either as a source of resistance or susceptibility. Besides the well-studied functions of non-coding RNAs related to plant development and abiotic stress responses, previous and recent discoveries have established that non-coding RNAs like miRNAs, siRNAs, lncRNAs and phasi-RNAs can fine tune plant defense responses by targeting various signaling pathways. In this review, recapitulation of previous reports associated with non-coding RNAs as a defense responder against virus, bacteria and fungus attacks and insightful discussion will lead us to conceive innovative ideas to fight against approaching threats of resistant breaking pathogens.
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Affiliation(s)
| | - Susmita Sett
- National Institute of Plant Genome Research, New Delhi, India.
| | - Tuhin Das
- National Institute of Plant Genome Research, New Delhi, India.
| | - Ashish Prasad
- Department of Botany, Kurukshetra University, Kurukshetra, India.
| | - Manoj Prasad
- National Institute of Plant Genome Research, New Delhi, India; Department of Plant Sciences, University of Hyderabad, Hyderabad, India.
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13
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Kumar S, Gupta N, Chakraborty S. Geminiviral betasatellites: critical viral ammunition to conquer plant immunity. Arch Virol 2023; 168:196. [PMID: 37386317 DOI: 10.1007/s00705-023-05776-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/30/2023] [Indexed: 07/01/2023]
Abstract
Geminiviruses have mastered plant cell modulation and immune invasion to ensue prolific infection. Encoding a relatively small number of multifunctional proteins, geminiviruses rely on satellites to efficiently re-wire plant immunity, thereby fostering virulence. Among the known satellites, betasatellites have been the most extensively investigated. They contribute significantly to virulence, enhance virus accumulation, and induce disease symptoms. To date, only two betasatellite proteins, βC1, and βV1, have been shown to play a crucial role in virus infection. In this review, we offer an overview of plant responses to betasatellites and counter-defense strategies deployed by betasatellites to overcome those responses.
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Affiliation(s)
- Sunil Kumar
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Neha Gupta
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
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14
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Liu S, Han Y, Li WX, Ding SW. Infection Defects of RNA and DNA Viruses Induced by Antiviral RNA Interference. Microbiol Mol Biol Rev 2023; 87:e0003522. [PMID: 37052496 PMCID: PMC10304667 DOI: 10.1128/mmbr.00035-22] [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] [Indexed: 04/14/2023] Open
Abstract
Immune recognition of viral genome-derived double-stranded RNA (dsRNA) molecules and their subsequent processing into small interfering RNAs (siRNAs) in plants, invertebrates, and mammals trigger specific antiviral immunity known as antiviral RNA interference (RNAi). Immune sensing of viral dsRNA is sequence-independent, and most regions of viral RNAs are targeted by virus-derived siRNAs which extensively overlap in sequence. Thus, the high mutation rates of viruses do not drive immune escape from antiviral RNAi, in contrast to other mechanisms involving specific virus recognition by host immune proteins such as antibodies and resistance (R) proteins in mammals and plants, respectively. Instead, viruses actively suppress antiviral RNAi at various key steps with a group of proteins known as viral suppressors of RNAi (VSRs). Some VSRs are so effective in virus counter-defense that potent inhibition of virus infection by antiviral RNAi is undetectable unless the cognate VSR is rendered nonexpressing or nonfunctional. Since viral proteins are often multifunctional, resistance phenotypes of antiviral RNAi are accurately defined by those infection defects of VSR-deletion mutant viruses that are efficiently rescued by host deficiency in antiviral RNAi. Here, we review and discuss in vivo infection defects of VSR-deficient RNA and DNA viruses resulting from the actions of host antiviral RNAi in model systems.
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Affiliation(s)
- Si Liu
- Department of Microbiology & Plant Pathology, University of California, Riverside, California, USA
- Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
| | - Yanhong Han
- Vector-borne Virus Research Center, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Wan-Xiang Li
- Department of Microbiology & Plant Pathology, University of California, Riverside, California, USA
- Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
| | - Shou-Wei Ding
- Department of Microbiology & Plant Pathology, University of California, Riverside, California, USA
- Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, California, USA
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15
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Liu H, Chang Z, Zhao S, Gong P, Zhang M, Lozano-Durán R, Yan H, Zhou X, Li F. Functional identification of a novel C7 protein of tomato yellow leaf curl virus. Virology 2023; 585:117-126. [PMID: 37331112 DOI: 10.1016/j.virol.2023.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 06/20/2023]
Abstract
Tomato yellow leaf curl virus (TYLCV) is a monopartite geminivirus, and one of the most devastating plant viruses in the world. TYLCV is traditionally known to encode six viral proteins in bidirectional and partially overlapping open reading frames (ORFs). However, recent studies have shown that TYLCV encodes additional small proteins with specific subcellular localizations and potential virulence functions. Here, a novel protein named C7, encoded by a newly-described ORF in the complementary strand, was identified as part of the TYLCV proteome using mass spectrometry. The C7 protein localized to the nucleus and cytoplasm, both in the absence and presence of the virus. C7 was found to interact with two other TYLCV-encoded proteins: with C2 in the nucleus, and with V2 in the cytoplasm, forming conspicuous granules. Mutation of C7 start codon ATG to ACG to block the translation of C7 delayed the onset of viral infection, and the mutant virus caused milder virus symptoms and less accumulations of viral DNAs and proteins. Using the potato virus X (PVX)-based recombinant vector, we found that ectopic overexpression of C7 resulted in more severe mosaic symptoms and promoted a higher accumulation of PVX-encoded coat protein in the late virus infection stage. In addition, C7 was also found to inhibit GFP-induced RNA silencing moderately. This study demonstrates that the novel C7 protein encoded by TYLCV is a pathogenicity factor and a weak RNA silencing suppressor, and that it plays a critical role during TYLCV infection.
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Affiliation(s)
- He Liu
- College of Plant Protection, Hebei Agricultural University, Baoding, Hebei, 071000, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Zhaoyang Chang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Siwen Zhao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Pan Gong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Mingzhen Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Rosa Lozano-Durán
- Department of Plant Biochemistry, Centre for Plant Molecular Biology (ZMBP), Eberhard Karls University, D-72076 Tübingen, Germany
| | - Hongfei Yan
- College of Plant Protection, Hebei Agricultural University, Baoding, Hebei, 071000, China.
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China; State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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16
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Hu W, Dai Z, Liu P, Deng C, Shen W, Li Z, Cui H. The Single Distinct Leader Protease Encoded by Alpinia oxyphylla Mosaic Virus (Genus Macluravirus) Suppresses RNA Silencing Through Interfering with Double-Stranded RNA Synthesis. PHYTOPATHOLOGY 2023; 113:1103-1114. [PMID: 36576401 DOI: 10.1094/phyto-10-22-0371-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The genomic 5'-terminal regions of viruses in the family Potyviridae (potyvirids) encode two types of leader proteases: serine-protease (P1) and cysteine-protease (HCPro), which differ greatly in the arrangement and sequence composition among inter-genus viruses. Most potyvirids have the same tandemly arranged P1 and HCPro, whereas viruses in the genus Macluravirus encode a single distinct leader protease, a truncated version of HCPro with yet-unknown functions. We investigated the RNA silencing suppression (RSS) activity and its underpinning mechanism of the distinct HCPro from alpinia oxyphylla mosaic macluravirus (aHCPro). Sequence analysis revealed that macluraviral HCPros have obvious truncations in the N-terminal and middle regions when aligned to their counterparts in potyviruses (well-characterized viral suppressors of RNA silencing). Nearly all defined elements essential for the RSS activity of potyviral counterparts are not distinguished in macluraviral HCPros. Here, we demonstrated that aHCPro exhibits a similar anti-silencing activity with the potyviral counterpart. However, aHCPro fails to block both the local and systemic spreading of RNA silencing. In line, aHCPro interferes with the dsRNA synthesis, an upstream step in the RNA silencing pathway. Affinity-purification and NanoLC-MS/MS analysis revealed that aHCPro has no association with core components or their potential interactors involving in dsRNA synthesis from the protein layer. Instead, the ectopic expression of aHCPro significantly reduces the transcript abundance of RDR2, RDR6, SGS3, and SDE5. This study represents the first report on the anti-silencing function of Macluravirus-encoded HCPro and the underlying molecular mechanism.
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Affiliation(s)
- Weiyao Hu
- Sanya Nanfan Research Institute, Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and College of Plant Protection, Hainan University, Haikou, Hainan, 570228, China
| | - Zhaoji Dai
- Sanya Nanfan Research Institute, Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and College of Plant Protection, Hainan University, Haikou, Hainan, 570228, China
| | - Peilan Liu
- Sanya Nanfan Research Institute, Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and College of Plant Protection, Hainan University, Haikou, Hainan, 570228, China
| | - Changhui Deng
- Sanya Nanfan Research Institute, Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and College of Plant Protection, Hainan University, Haikou, Hainan, 570228, China
| | - Wentao Shen
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, Hainan, 571101, China
| | - Zengping Li
- Sanya Nanfan Research Institute, Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and College of Plant Protection, Hainan University, Haikou, Hainan, 570228, China
| | - Hongguang Cui
- Sanya Nanfan Research Institute, Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Ministry of Education) and College of Plant Protection, Hainan University, Haikou, Hainan, 570228, China
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17
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Cao B, Ge L, Zhang M, Li F, Zhou X. Geminiviral C2 proteins inhibit active autophagy to facilitate virus infection by impairing the interaction of ATG7 and ATG8. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:1328-1343. [PMID: 36639894 DOI: 10.1111/jipb.13452] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 01/13/2023] [Indexed: 05/13/2023]
Abstract
Autophagy is a conserved intracellular degradation process that plays an active role in plant response to virus infections. Here we report that geminiviruses counteract activated autophagy-mediated antiviral defense in plant cells through the C2 proteins they encode. We found that, in Nicotiana benthamiana plants, tomato leaf curl Yunnan virus (TLCYnV) infection upregulated the transcription levels of autophagy-related genes (ATGs). Overexpression of NbATG5, NbATG7, or NbATG8a in N. benthamiana plants decreased TLCYnV accumulation and attenuated viral symptoms. Interestingly, transgenic overexpression of NbATG7 promoted the growth of N. benthamiana plants and enhanced plant resistance to TLCYnV. We further revealed that the C2 protein encoded by TLCYnV directly interacted with the ubiquitin-activating domain of ATG7. This interaction competitively disrupted the ATG7-ATG8 binding in N. benthamiana and Solanum lycopersicum plants, thereby inhibiting autophagy activity. Furthermore, we uncovered that the C2-mediated autophagy inhibition mechanism was conserved in three other geminiviruses. In summary, we discovered a novel counter-defensive strategy employed by geminiviruses that enlists their C2 proteins as disrupters of ATG7-ATG8 interactions to defeat antiviral autophagy.
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Affiliation(s)
- Buwei Cao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Linhao Ge
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Mingzhen Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
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18
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Ding SW. Transgene Silencing, RNA Interference, and the Antiviral Defense Mechanism Directed by Small Interfering RNAs. PHYTOPATHOLOGY 2023; 113:616-625. [PMID: 36441873 DOI: 10.1094/phyto-10-22-0358-ia] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
One important discovery in plant pathology over recent decades is the natural antiviral defense mechanism mediated by RNA interference (RNAi). In antiviral RNAi, virus infection triggers Dicer processing of virus-specific double-stranded RNA into small interfering RNAs (siRNAs). Frequently, further amplified by host enzyme and cofactors, these virus-derived siRNAs direct specific virus clearance in an Argonaute protein-containing effector complex. The siRNAs derived from viruses and viroids accumulate to very high levels during infection. Because they overlap extensively in nucleotide sequence, this allows for deep sequencing and bioinformatics assembly of total small RNAs for rapid discovery and identification of viruses and viroids. Antiviral RNAi acts as the primary defense mechanism against both RNA and DNA viruses in plants, yet viruses still successfully infect plants. They do so because all currently recognized plant viruses combat the RNAi response by encoding at least one protein as a viral suppressor of RNAi (VSR) required for infection, even though plant viruses have small genome sizes with a limited coding capacity. This review article will recapitulate the key findings that have revealed the genetic pathway for the biogenesis and antiviral activity of viral siRNAs and the specific role of VSRs in infection by antiviral RNAi suppression. Moreover, early pioneering studies on transgene silencing, RNAi, and virus-plant/virus-virus interactions paved the road to the discovery of antiviral RNAi.
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Affiliation(s)
- Shou-Wei Ding
- Department of Microbiology & Plant Pathology and Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California, Riverside, CA
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19
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Matsumura EE, Kormelink R. Small Talk: On the Possible Role of Trans-Kingdom Small RNAs during Plant-Virus-Vector Tritrophic Communication. PLANTS (BASEL, SWITZERLAND) 2023; 12:1411. [PMID: 36987098 PMCID: PMC10059270 DOI: 10.3390/plants12061411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 06/19/2023]
Abstract
Small RNAs (sRNAs) are the hallmark and main effectors of RNA silencing and therefore are involved in major biological processes in plants, such as regulation of gene expression, antiviral defense, and plant genome integrity. The mechanisms of sRNA amplification as well as their mobile nature and rapid generation suggest sRNAs as potential key modulators of intercellular and interspecies communication in plant-pathogen-pest interactions. Plant endogenous sRNAs can act in cis to regulate plant innate immunity against pathogens, or in trans to silence pathogens' messenger RNAs (mRNAs) and impair virulence. Likewise, pathogen-derived sRNAs can act in cis to regulate expression of their own genes and increase virulence towards a plant host, or in trans to silence plant mRNAs and interfere with host defense. In plant viral diseases, virus infection alters the composition and abundance of sRNAs in plant cells, not only by triggering and interfering with the plant RNA silencing antiviral response, which accumulates virus-derived small interfering RNAs (vsiRNAs), but also by modulating plant endogenous sRNAs. Here, we review the current knowledge on the nature and activity of virus-responsive sRNAs during virus-plant interactions and discuss their role in trans-kingdom modulation of virus vectors for the benefit of virus dissemination.
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20
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A Zinc Finger Motif in the P1 N Terminus, Highly Conserved in a Subset of Potyviruses, Is Associated with the Host Range and Fitness of Telosma Mosaic Virus. J Virol 2023; 97:e0144422. [PMID: 36688651 PMCID: PMC9972955 DOI: 10.1128/jvi.01444-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
P1 is the first protein translated from the genomes of most viruses in the family Potyviridae, and it contains a C-terminal serine-protease domain that cis-cleaves the junction between P1 and HCPro in most cases. Intriguingly, P1 is the most divergent among all mature viral factors, and its roles during viral infection are still far from understood. In this study, we found that telosma mosaic virus (TelMV, genus Potyvirus) in passion fruit, unlike TelMV isolates present in other hosts, has two stretches at the P1 N terminus, named N1 and N2, with N1 harboring a Zn finger motif. Further analysis revealed that at least 14 different potyviruses, mostly belonging to the bean common mosaic virus subgroup, encode a domain equivalent to N1. Using the newly developed TelMV infectious cDNA clones from passion fruit, we demonstrated that N1, but not N2, is crucial for viral infection in both Nicotiana benthamiana and passion fruit. The regulatory effects of N1 domain on P1 cis cleavage, as well as the accumulation and RNA silencing suppression (RSS) activity of its cognate HCPro, were comprehensively investigated. We found that N1 deletion decreases HCPro abundance at the posttranslational level, likely by impairing P1 cis cleavage, thus reducing HCPro-mediated RSS activity. Remarkably, disruption of the Zn finger motif in N1 did not impair P1 cis cleavage and HCPro accumulation but severely debilitated TelMV fitness. Therefore, our results suggest that the Zn finger motif in P1s plays a critical role in viral infection that is independent of P1 protease activity and self-release, as well as HCPro accumulation and silencing suppression. IMPORTANCE Viruses belonging to the family Potyviridae represent the largest group of plant-infecting RNA viruses, including a variety of agriculturally and economically important viral pathogens. Like all picorna-like viruses, potyvirids employ polyprotein processing as the gene expression strategy. P1, the first protein translated from most potyvirid genomes, is the most variable viral factor and has attracted great scientific interest. Here, we defined a Zn finger motif-encompassing domain (N1) at the N terminus of P1 among diverse potyviruses phylogenetically related to bean common mosaic virus. Using TelMV as a model virus, we demonstrated that the N1 domain is key for viral infection, as it is involved both in regulating the abundance of its cognate HCPro and in an as-yet-undefined key function unrelated to protease processing and RNA silencing suppression. These results advance our knowledge of the hypervariable potyvirid P1s and highlight the importance for infection of a previously unstudied Zn finger domain at the P1 N terminus.
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Zhang J, Ma M, Liu Y, Ismayil A. Plant Defense and Viral Counter-Defense during Plant-Geminivirus Interactions. Viruses 2023; 15:v15020510. [PMID: 36851725 PMCID: PMC9964946 DOI: 10.3390/v15020510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/17/2023] Open
Abstract
Geminiviruses are the largest family of plant viruses that cause severe diseases and devastating yield losses of economically important crops worldwide. In response to geminivirus infection, plants have evolved ingenious defense mechanisms to diminish or eliminate invading viral pathogens. However, increasing evidence shows that geminiviruses can interfere with plant defense response and create a suitable cell environment by hijacking host plant machinery to achieve successful infections. In this review, we discuss recent findings about plant defense and viral counter-defense during plant-geminivirus interactions.
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Affiliation(s)
- Jianhang Zhang
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China
| | - Mengyuan Ma
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Asigul Ismayil
- Key Laboratory of Xinjiang Phytomedicine Resource and Utilization of Ministry of Education, College of Life Sciences, Shihezi University, Shihezi 832003, China
- Correspondence:
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22
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Sehki H, Yu A, Elmayan T, Vaucheret H. TYMV and TRV infect Arabidopsis thaliana by expressing weak suppressors of RNA silencing and inducing host RNASE THREE LIKE1. PLoS Pathog 2023; 19:e1010482. [PMID: 36696453 PMCID: PMC9901757 DOI: 10.1371/journal.ppat.1010482] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 02/06/2023] [Accepted: 01/10/2023] [Indexed: 01/26/2023] Open
Abstract
Post-Transcriptional Gene Silencing (PTGS) is a defense mechanism that targets invading nucleic acids of endogenous (transposons) or exogenous (pathogens, transgenes) origins. During plant infection by viruses, virus-derived primary siRNAs target viral RNAs, resulting in both destruction of single-stranded viral RNAs (execution step) and production of secondary siRNAs (amplification step), which maximizes the plant defense. As a counter-defense, viruses express proteins referred to as Viral Suppressor of RNA silencing (VSR). Some viruses express VSRs that totally inhibit PTGS, whereas other viruses express VSRs that have limited effect. Here we show that infection with the Turnip yellow mosaic virus (TYMV) is enhanced in Arabidopsis ago1, ago2 and dcl4 mutants, which are impaired in the execution of PTGS, but not in dcl2, rdr1 and rdr6 mutants, which are impaired in the amplification of PTGS. Consistently, we show that the TYMV VSR P69 localizes in siRNA-bodies, which are the site of production of secondary siRNAs, and limits PTGS amplification. Moreover, TYMV induces the production of the host enzyme RNASE THREE-LIKE 1 (RTL1) to further reduce siRNA accumulation. Infection with the Tobacco rattle virus (TRV), which also encodes a VSR limiting PTGS amplification, induces RTL1 as well to reduce siRNA accumulation and promote infection. Together, these results suggest that RTL1 could be considered as a host susceptibility gene that is induced by viruses as a strategy to further limit the plant PTGS defense when VSRs are insufficient.
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Affiliation(s)
- Hayat Sehki
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
- Université Paris-Sud, Université Paris-Saclay, Orsay, France
| | - Agnès Yu
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Taline Elmayan
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
| | - Hervé Vaucheret
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, France
- * E-mail:
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Zhang M, Cao B, Zhang H, Fan Z, Zhou X, Li F. Geminivirus satellite-encoded βC1 activates UPR, induces bZIP60 nuclear export, and manipulates the expression of bZIP60 downstream genes to benefit virus infection. SCIENCE CHINA LIFE SCIENCES 2022:10.1007/s11427-022-2196-y. [DOI: 10.1007/s11427-022-2196-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 09/20/2022] [Indexed: 12/14/2022]
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24
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Liu C, Zhang J, Wang J, Liu W, Wang K, Chen X, Wen Y, Tian S, Pu Y, Fan G, Ma X, Sun X. Tobacco mosaic virus hijacks its coat protein-interacting protein IP-L to inhibit NbCML30, a calmodulin-like protein, to enhance its infection. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:677-693. [PMID: 36087000 DOI: 10.1111/tpj.15972] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 09/06/2022] [Accepted: 09/08/2022] [Indexed: 06/15/2023]
Abstract
Calcium is an important plant immune signal that is essential for activating host resistance, but how RNA viruses manipulate calcium signals to promote their infections remains largely unknown. Here, we demonstrated that tobacco mosaic virus (TMV) coat protein (CP)-interacting protein L (IP-L) associates with calmodulin-like protein 30 (NbCML30) in the cytoplasm and nucleus, and can suppress its expression at the nucleic acid and protein levels. NbCML30, which lacks the EF-hand conserved domain and cannot bind to Ca2+ , was located in the cytoplasm and nucleus and was downregulated by TMV infection. NbCML30 silencing promoted TMV infection, while its overexpression inhibited TMV infection by activating Ca2+ -dependent oxidative stress in plants. NbCML30-mediated resistance to TMV mainly depends on IP-L regulation as the facilitation of TMV infection by silencing NbCML30 was canceled by co-silencing NbCML30 and IP-L. Overall, these findings indicate that in the absence of any reported silencing suppressor activity, TMV CP manipulates IP-L to inhibit NbCML30, influencing its Ca2+ -dependent role in the oxidative stress response. These results lay a theoretical foundation that will enable us to engineer tobacco (Nicotiana spp.) with improved TMV resistance in the future.
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Affiliation(s)
- Changyun Liu
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Jian Zhang
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Jing Wang
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Weina Liu
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Ke Wang
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Xue Chen
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Yuxia Wen
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Shaorui Tian
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Yundan Pu
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Guangjin Fan
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Xiaozhou Ma
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
| | - Xianchao Sun
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, 400716, People's Republic of China
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25
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Gong Q, Wang Y, Jin Z, Hong Y, Liu Y. Transcriptional and post-transcriptional regulation of RNAi-related gene expression during plant-virus interactions. STRESS BIOLOGY 2022; 2:33. [PMID: 37676459 PMCID: PMC10441928 DOI: 10.1007/s44154-022-00057-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 08/14/2022] [Indexed: 09/08/2023]
Abstract
As sessile organisms, plants encounter diverse invasions from pathogens including viruses. To survive and thrive, plants have evolved multilayered defense mechanisms to combat virus infection. RNAi, also known as RNA silencing, is an across-kingdom innate immunity and gene regulatory machinery. Molecular framework and crucial roles of RNAi in antiviral defense have been well-characterized. However, it is largely unknown that how RNAi is transcriptionally regulated to initiate, maintain and enhance cellular silencing under normal or stress conditions. Recently, insights into the transcriptional and post-transcriptional regulation of RNAi-related genes in different physiological processes have been emerging. In this review, we integrate these new findings to provide updated views on how plants modulate RNAi machinery at the (post-) transcriptional level to respond to virus infection.
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Affiliation(s)
- Qian Gong
- MOE Key Laboratory of Bioinformatics and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Yunjing Wang
- MOE Key Laboratory of Bioinformatics and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China
| | - Zhenhui Jin
- Research Centre for Plant RNA Signaling, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 311121, China
- School of Science and the Environment, University of Worcester, Worcester, WR2 6AJ, UK
| | - Yiguo Hong
- Research Centre for Plant RNA Signaling, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 311121, China
- School of Science and the Environment, University of Worcester, Worcester, WR2 6AJ, UK
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Yule Liu
- MOE Key Laboratory of Bioinformatics and Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China.
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26
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Wang Y, Liu H, Wang Z, Guo Y, Hu T, Zhou X. P25 and P37 proteins encoded by firespike leafroll-associated virus are viral suppressors of RNA silencing. Front Microbiol 2022; 13:964156. [PMID: 36051767 PMCID: PMC9424829 DOI: 10.3389/fmicb.2022.964156] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/27/2022] [Indexed: 11/13/2022] Open
Abstract
Firespike leafroll-associated virus (FLRaV) is a major pathogen associated with firespike (Odontonema tubaeforme) leafroll disease. Phylogenetic analysis showed that FLRaV possesses typical traits of subgroup II members of ampeloviruses, but encodes two additional proteins, P25 and P37. Here, we determined the microfilament localization of P25 protein. Posttranscriptional gene silencing (PTGS) assay showed that both FLRaV P25 and P37 were able to suppress the local and systemic PTGS and FLRaV P25 was capable of suppressing the green fluorescent protein (GFP) gene silencing triggered by both sense RNA-induced PTGS (S-PTGS) and inverted repeat RNA-induced PTGS (IR-PTGS). In contrast, FLRaV P37 was only able to inhibit the GFP silencing triggered by the S-PTGS but not the IR-PTGS. In the transcriptional gene silencing (TGS) assay, only FLRaV P25 was found to be able to reverse established TGS-mediated silencing of GFP in 16-TGS plants. We also found that FLRaV P25 could aggravate the disease symptom and viral titer of potato virus X in N. benthamiana. These results suggest that FLRaV P25 and P37 may have crucial roles in overcoming host RNA silencing, which provides key insights into our understanding of the molecular mechanisms underlying FLRaV infection.
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Affiliation(s)
- Yaqin Wang
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Hui Liu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Zhanqi Wang
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, College of Life Sciences, Huzhou University, Huzhou, China
| | - Yushuang Guo
- Key Laboratory of Molecular Genetics, Guizhou Academy of Tobacco Science, Guiyang, China
| | - Tao Hu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- *Correspondence: Tao Hu,
| | - Xueping Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- Xueping Zhou,
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27
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Shang K, Xu Y, Cao W, Xie X, Zhang Y, Zhang J, Liu H, Zhou S, Zhu X, Zhu C. Potato (Solanum tuberosum L.) non-specific lipid transfer protein StLTP6 promotes viral infection by inhibiting virus-induced RNA silencing. PLANTA 2022; 256:54. [PMID: 35927530 DOI: 10.1007/s00425-022-03948-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
For the first time it is reported that members of the nsLTP protein family could promote viral infection by inhibiting virus-induced RNA silencing. Non-specific lipid transfer proteins (nsLTPs) are a class of soluble proteins with low relative molecular weight and widely present in higher plants. The role of nsLTPs in biotic and abiotic stresses has been studied, but no report has shown that nsLTPs play a role in the process of viral infection. We report the function and mechanism of the classical nsLTP protein StLTP6 in viral infection. We found that StLTP6 expression was remarkably upregulated in potato infected with potato virus Y and potato virus S. The infection efficiency and virus content of StLTP6-overexpressed potato and Nicotiana benthamiana were remarkable increased. Further study found that the overexpression of StLTP6 inhibited the expression of multiple genes in the RNA silencing pathway, thereby inhibiting virus-induced RNA silencing. This result indicated that StLTP6 expression was induced during viral infection to inhibit the resistance of virus-induced RNA silencing and promote viral infection. In summary, we reported the role of StLTP6 in viral infection, broadening the biological function range of the nsLTP family and providing valuable information for the study of viral infection mechanism.
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Affiliation(s)
- Kaijie Shang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
- College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Yang Xu
- Shandong Peanut Research Institute, Shandong Academy of Agricultural Sciences, Qingdao, 266100, China
| | - Weilin Cao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Xiaoying Xie
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Yanru Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Jingfeng Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Hongmei Liu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Shumei Zhou
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China
| | - Xiaoping Zhu
- College of Plant Protection, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
| | - Changxiang Zhu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, Shandong, China.
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28
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Akbar S, Wei Y, Zhang MQ. RNA Interference: Promising Approach to Combat Plant Viruses. Int J Mol Sci 2022; 23:ijms23105312. [PMID: 35628126 PMCID: PMC9142109 DOI: 10.3390/ijms23105312] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/06/2022] [Accepted: 05/07/2022] [Indexed: 11/16/2022] Open
Abstract
Plant viruses are devastating plant pathogens that severely affect crop yield and quality. Plants have developed multiple lines of defense systems to combat viral infection. Gene silencing/RNA interference is the key defense system in plants that inhibits the virulence and multiplication of pathogens. The general mechanism of RNAi involves (i) the transcription and cleavage of dsRNA into small RNA molecules, such as microRNA (miRNA), or small interfering RNA (siRNA), (ii) the loading of siRNA/miRNA into an RNA Induced Silencing Complex (RISC), (iii) complementary base pairing between siRNA/miRNA with a targeted gene, and (iv) the cleavage or repression of a target gene with an Argonaute (AGO) protein. This natural RNAi pathway could introduce transgenes targeting various viral genes to induce gene silencing. Different RNAi pathways are reported for the artificial silencing of viral genes. These include Host-Induced Gene Silencing (HIGS), Virus-Induced Gene Silencing (VIGS), and Spray-Induced Gene Silencing (SIGS). There are significant limitations in HIGS and VIGS technology, such as lengthy and time-consuming processes, off-target effects, and public concerns regarding genetically modified (GM) transgenic plants. Here, we provide in-depth knowledge regarding SIGS, which efficiently provides RNAi resistance development against targeted genes without the need for GM transgenic plants. We give an overview of the defense system of plants against viral infection, including a detailed mechanism of RNAi, small RNA molecules and their types, and various kinds of RNAi pathways. This review will describe how RNA interference provides the antiviral defense, recent improvements, and their limitations.
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Affiliation(s)
- Sehrish Akbar
- Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory for Conservation and Utilization of Agro Bioresources, Guangxi University, Nanning 530005, China; (S.A.); (Y.W.)
| | - Yao Wei
- Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory for Conservation and Utilization of Agro Bioresources, Guangxi University, Nanning 530005, China; (S.A.); (Y.W.)
| | - Mu-Qing Zhang
- Guangxi Key Laboratory for Sugarcane Biology & State Key Laboratory for Conservation and Utilization of Agro Bioresources, Guangxi University, Nanning 530005, China; (S.A.); (Y.W.)
- IRREC-IFAS, University of Florida, Fort Pierce, FL 34945, USA
- Correspondence: or
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29
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Ray S, Casteel CL. Effector-mediated plant-virus-vector interactions. THE PLANT CELL 2022; 34:1514-1531. [PMID: 35277714 PMCID: PMC9048964 DOI: 10.1093/plcell/koac058] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 02/14/2022] [Indexed: 05/30/2023]
Abstract
Hemipterans (such as aphids, whiteflies, and leafhoppers) are some of the most devastating insect pests due to the numerous plant pathogens they transmit as vectors, which are primarily viral. Over the past decade, tremendous progress has been made in broadening our understanding of plant-virus-vector interactions, yet on the molecular level, viruses and vectors have typically been studied in isolation of each other until recently. From that work, it is clear that both hemipteran vectors and viruses use effectors to manipulate host physiology and successfully colonize a plant and that co-evolutionary dynamics have resulted in effective host immune responses, as well as diverse mechanisms of counterattack by both challengers. In this review, we focus on advances in effector-mediated plant-virus-vector interactions and the underlying mechanisms. We propose that molecular synergisms in vector-virus interactions occur in cases where both the virus and vector benefit from the interaction (mutualism). To support this view, we show that mutualisms are common in virus-vector interactions and that virus and vector effectors target conserved mechanisms of plant immunity, including plant transcription factors, and plant protein degradation pathways. Finally, we outline ways to identify true effector synergisms in the future and propose future research directions concerning the roles effectors play in plant-virus-vector interactions.
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Affiliation(s)
- Swayamjit Ray
- School of Integrative Plant Science, Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, New York 14850, USA
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30
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Zhao S, Gong P, Ren Y, Liu H, Li H, Li F, Zhou X. The novel C5 protein from tomato yellow leaf curl virus is a virulence factor and suppressor of gene silencing. STRESS BIOLOGY 2022; 2:19. [PMID: 37676365 PMCID: PMC10442036 DOI: 10.1007/s44154-022-00044-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 03/07/2022] [Indexed: 09/08/2023]
Abstract
Tomato yellow leaf curl virus (TYLCV) is known to encode 6 canonical viral proteins. Our recent study revealed that TYLCV also encodes some additional small proteins with potential virulence functions. The fifth ORF of TYLCV in the complementary sense, which we name C5, is evolutionarily conserved, but little is known about its expression and function during viral infection. Here, we confirmed the expression of the TYLCV C5 by analyzing the promoter activity of its upstream sequences and by detecting the C5 protein in infected cells by using a specific custom-made antibody. Ectopic expression of C5 using a potato virus X (PVX) vector resulted in severe mosaic symptoms and higher virus accumulation levels followed by a burst of reactive oxygen species (ROS) in Nicotiana benthamiana plants. C5 was able to effectively suppress local and systemic post-transcriptional gene silencing (PTGS) induced by single-stranded GFP but not double-stranded GFP, and reversed the transcriptional gene silencing (TGS) of GFP. Furthermore, the mutation of C5 in TYLCV inhibited viral replication and the development of disease symptoms in infected plants. Transgenic overexpression of C5 could complement the virulence of a TYLCV infectious clone encoding a dysfunctional C5. Collectively, this study reveals that TYLCV C5 is a pathogenicity determinant and RNA silencing suppressor, hence expanding our knowledge of the functional repertoire of the TYLCV proteome.
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Affiliation(s)
- Siwen Zhao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Pan Gong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yanxiang Ren
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Hui Liu
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Zhejiang, 310058, Hangzhou, China
| | - Hao Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Zhejiang, 310058, Hangzhou, China.
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31
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Jin L, Chen M, Xiang M, Guo Z. RNAi-Based Antiviral Innate Immunity in Plants. Viruses 2022; 14:v14020432. [PMID: 35216025 PMCID: PMC8875485 DOI: 10.3390/v14020432] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 12/13/2022] Open
Abstract
Multiple antiviral immunities were developed to defend against viral infection in hosts. RNA interference (RNAi)-based antiviral innate immunity is evolutionarily conserved in eukaryotes and plays a vital role against all types of viruses. During the arms race between the host and virus, many viruses evolve viral suppressors of RNA silencing (VSRs) to inhibit antiviral innate immunity. Here, we reviewed the mechanism at different stages in RNAi-based antiviral innate immunity in plants and the counteractions of various VSRs, mainly upon infection of RNA viruses in model plant Arabidopsis. Some critical challenges in the field were also proposed, and we think that further elucidating conserved antiviral innate immunity may convey a broad spectrum of antiviral strategies to prevent viral diseases in the future.
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32
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Gui X, Liu C, Qi Y, Zhou X. Geminiviruses employ host DNA glycosylases to subvert DNA methylation-mediated defense. Nat Commun 2022; 13:575. [PMID: 35102164 PMCID: PMC8803994 DOI: 10.1038/s41467-022-28262-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 01/12/2022] [Indexed: 01/13/2023] Open
Abstract
DNA methylation is an epigenetic mechanism that plays important roles in gene regulation and transposon silencing. Active DNA demethylation has evolved to counterbalance DNA methylation at many endogenous loci. Here, we report that active DNA demethylation also targets viral DNAs, tomato yellow leaf curl China virus (TYLCCNV) and its satellite tomato yellow leaf curl China betasatellite (TYLCCNB), to promote their virulence. We demonstrate that the βC1 protein, encoded by TYLCCNB, interacts with a ROS1-like DNA glycosylase in Nicotiana benthamiana and with the DEMETER (DME) DNA glycosylase in Arabidopsis thaliana. The interaction between βC1 and DME facilitates the DNA glycosylase activity to decrease viral DNA methylation and promote viral virulence. These findings reveal that active DNA demethylation can be regulated by a viral protein to subvert DNA methylation-mediated defense.
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Affiliation(s)
- Xiaojian Gui
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Chang Liu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yijun Qi
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
| | - Xueping Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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33
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Wu W, Luo X, Ren M. Clearance or Hijack: Universal Interplay Mechanisms Between Viruses and Host Autophagy From Plants to Animals. Front Cell Infect Microbiol 2022; 11:786348. [PMID: 35047417 PMCID: PMC8761674 DOI: 10.3389/fcimb.2021.786348] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/10/2021] [Indexed: 12/24/2022] Open
Abstract
Viruses typically hijack the cellular machinery of their hosts for successful infection and replication, while the hosts protect themselves against viral invasion through a variety of defense responses, including autophagy, an evolutionarily ancient catabolic pathway conserved from plants to animals. Double-membrane vesicles called autophagosomes transport trapped viral cargo to lysosomes or vacuoles for degradation. However, during an ongoing evolutionary arms race, viruses have acquired a strong ability to disrupt or even exploit the autophagy machinery of their hosts for successful invasion. In this review, we analyze the universal role of autophagy in antiviral defenses in animals and plants and summarize how viruses evade host immune responses by disrupting and manipulating host autophagy. The review provides novel insights into the role of autophagy in virus–host interactions and offers potential targets for the prevention and control of viral infection in both plants and animals.
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Affiliation(s)
- Wenxian Wu
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu Agricultural Science and Technology Center, Chengdu, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Science of Zhengzhou University, Zhengzhou, China.,Hainan Yazhou Bay Seed Laboratory, Sanya, China
| | - Xiumei Luo
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu Agricultural Science and Technology Center, Chengdu, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Science of Zhengzhou University, Zhengzhou, China.,Hainan Yazhou Bay Seed Laboratory, Sanya, China.,Key Laboratory of Plant Hormones and Development Regulation of Chongqing, School of Life Sciences, Chongqing University, Chongqing, China
| | - Maozhi Ren
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu Agricultural Science and Technology Center, Chengdu, China.,Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Science of Zhengzhou University, Zhengzhou, China.,Hainan Yazhou Bay Seed Laboratory, Sanya, China
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Devendran R, Namgial T, Reddy KK, Kumar M, Zarreen F, Chakraborty S. Insights into the multifunctional roles of geminivirus-encoded proteins in pathogenesis. Arch Virol 2022; 167:307-326. [PMID: 35079902 DOI: 10.1007/s00705-021-05338-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 10/23/2021] [Indexed: 12/18/2022]
Abstract
Geminiviruses are a major threat to agriculture in tropical and subtropical regions of the world. Geminiviruses have small genome with limited coding capacity. Despite this limitation, these viruses have mastered hijacking the host cellular metabolism for their survival. To compensate for the small size of their genome, geminiviruses encode multifunctional proteins. In addition, geminiviruses associate themselves with satellite DNA molecules which also encode proteins that support the virus in establishing successful infection. Geminiviral proteins recruit multiple host factors, suppress the host defense, and manipulate host metabolism to establish infection. We have updated the knowledge accumulated about the proteins of geminiviruses and their satellites in the context of pathogenesis in a single review. We also discuss their interactions with host factors to provide a mechanistic understanding of the infection process.
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Affiliation(s)
- Ragunathan Devendran
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Tsewang Namgial
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Kishore Kumar Reddy
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Manish Kumar
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Fauzia Zarreen
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
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Zhao L, Che X, Wang Z, Zhou X, Xie Y. Functional Characterization of Replication-Associated Proteins Encoded by Alphasatellites Identified in Yunnan Province, China. Viruses 2022; 14:222. [PMID: 35215816 PMCID: PMC8875141 DOI: 10.3390/v14020222] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/17/2022] [Accepted: 01/21/2022] [Indexed: 12/20/2022] Open
Abstract
Alphasatellites, which encode only a replication-associated protein (alpha-Rep), are frequently found to be non-essential satellite components associated with begomovirus/betasatellite complexes, and their presence can modulate disease symptoms and/or viral DNA accumulation during infection. Our previous study has shown that there are three types of alphasatellites associated with begomovirus/betasatellite complexes in Yunnan province in China and they encode three corresponding types of alpha-Rep proteins. However, the biological functions of alpha-Reps remain poorly understood. In this study, we investigated the biological functions of alpha-Reps in post-transcriptional gene silencing (PTGS) and transcriptional gene silencing (TGS) using 16c and 16-TGS transgenic Nicotiana benthamiana plants. Results showed that all the three types of alpha-Rep proteins were capable of suppressing the PTGS and reversing the TGS. Among them, the alpha-Rep of Y10DNA1 has the strongest PTGS and TGS suppressor activities. We also found that the alpha-Rep proteins were able to increase the accumulation of their helper virus during coinfection. These results suggest that the alpha-Reps may have a role in overcoming host defense, which provides a possible explanation for the selective advantage provided by the association of alphasatellites with begomovirus/betasatellite complexes.
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Affiliation(s)
- Liling Zhao
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (L.Z.); (X.C.); (X.Z.)
- Biotechnology and Germplasm Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming 650223, China
| | - Xuan Che
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (L.Z.); (X.C.); (X.Z.)
| | - Zhanqi Wang
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, College of Life Sciences, Huzhou University, Huzhou 313000, China;
| | - Xueping Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (L.Z.); (X.C.); (X.Z.)
- Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yan Xie
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (L.Z.); (X.C.); (X.Z.)
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Zhang M, Gong P, Ge L, Li Y, Chang Z, Qiao R, Zhou X, Wang A, Li F. Nuclear Exportin 1 (XPO1) Binds to the Nuclear Localization/Export Signal of the Turnip Mosaic Virus NIb to Promote Viral Infection. Front Microbiol 2022; 12:780724. [PMID: 35058899 PMCID: PMC8763854 DOI: 10.3389/fmicb.2021.780724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 11/08/2021] [Indexed: 11/25/2022] Open
Abstract
The nuclear localization signal (NLS) and nuclear export signal (NES) are key signatures of proteins for controlling nuclear import and export. The NIb protein of turnip mosaic virus (TuMV) is an RNA-dependent RNA polymerase (RdRP) that is absolutely required for viral genome replication. Previous studies have shown that NIb is a nucleocytoplasmic shuttling protein and contains four putative NES and four putative NLS motifs. Here, we analyzed the function of these NESs and NLSs, and identified two functional NESs and one functional NLS. Mutation of the identified functional NESs or NLS inhibited viral RNA accumulation and systemic infection. Exportin 1 (XPO1) is a nuclear export receptor that binds directly to cargo proteins harboring a leucine-rich NES and translocates them to the cytoplasm. We found that XPO1 contains two NIb-binding domains, which recognize the NLS and NES of NIb, respectively, to mediate the nucleocytoplasmic transport of NIb and promote viral infection. Taken together, these data suggest that the nucleocytoplasmic transport of NIb is modulated by XPO1 through its interactions with the functional NLS and NES of NIb to promote viral infection.
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Affiliation(s)
- Mingzhen Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Pan Gong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Linhao Ge
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yinzi Li
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada.,Department of Biology, Western University, London, ON, Canada
| | - Zhaoyang Chang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Rui Qiao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.,State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada.,Department of Biology, Western University, London, ON, Canada
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Small RNAs Participate in Plant-Virus Interaction and Their Application in Plant Viral Defense. Int J Mol Sci 2022; 23:ijms23020696. [PMID: 35054880 PMCID: PMC8775341 DOI: 10.3390/ijms23020696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 12/30/2021] [Accepted: 01/05/2022] [Indexed: 02/06/2023] Open
Abstract
Small RNAs are significant regulators of gene expression, which play multiple roles in plant development, growth, reproductive and stress response. It is generally believed that the regulation of plants’ endogenous genes by small RNAs has evolved from a cellular defense mechanism for RNA viruses and transposons. Most small RNAs have well-established roles in the defense response, such as viral response. During viral infection, plant endogenous small RNAs can direct virus resistance by regulating the gene expression in the host defense pathway, while the small RNAs derived from viruses are the core of the conserved and effective RNAi resistance mechanism. As a counter strategy, viruses evolve suppressors of the RNAi pathway to disrupt host plant silencing against viruses. Currently, several studies have been published elucidating the mechanisms by which small RNAs regulate viral defense in different crops. This paper reviews the distinct pathways of small RNAs biogenesis and the molecular mechanisms of small RNAs mediating antiviral immunity in plants, as well as summarizes the coping strategies used by viruses to override this immune response. Finally, we discuss the current development state of the new applications in virus defense based on small RNA silencing.
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Li F, Wang A. Transient Expression-Mediated Gene Silencing in Plants and Suppression of Gene Silencing with Viral Suppressors. Methods Mol Biol 2022; 2400:33-41. [PMID: 34905188 DOI: 10.1007/978-1-0716-1835-6_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Posttranscriptional gene silencing (PTGS) also known as RNA silencing or RNA interference is an evolutionarily conserved innate immunity in eukaryotes that targets the complementary RNA sequences to slice/degrade the target RNA or repress the translation of mRNA. In the past two decades, RNA silencing as an important antiviral mechanism has been studied extensively in plants. Intriguingly, almost every virus encodes at least a viral suppressor of RNA silencing (VSR) to counterattack RNA silencing with many strategies to interfere with different steps of RNA silencing. Therefore, the molecular identification of VSRs and elucidation of their functional mechanisms contribute to a better understanding of host resistance and viral pathogenicity. Here, we describe a protocol for the transient expression-induced gene silencing in 16c GFP transgenic and wild type Nicotiana benthamiana plants, and the suppression of single-stranded GFP and double-stranded GFP induced RNA silencing with a VSR in N. benthamiana plants. This protocol is simple and can serve as a standard for the identification and functional analysis of a VSR.
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Affiliation(s)
- Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
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Gao Y, Yang J, Zhang X, Chen A, Gu Z, Du Z. The Weak Small RNA-Binding Activity of the 2b Proteins of Subgroup II Cucumber Mosaic Virus Strains Is Insufficient for RNA Silencing Suppression. Front Microbiol 2021; 12:760937. [PMID: 34745069 PMCID: PMC8569468 DOI: 10.3389/fmicb.2021.760937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 09/15/2021] [Indexed: 11/13/2022] Open
Abstract
The 2b proteins encoded by cucumber mosaic virus (CMV) subgroup I strains suppress RNA silencing primarily by competitively binding small RNAs (sRNAs) in the host cell cytoplasm. Interestingly, 2b proteins encoded by CMV subgroup II strains accumulate predominantly in nuclei. Here we determined that whereas the 2b protein (Fny2b) of subgroup IA strain Fny-CMV is highly effective in suppressing both sense RNA-induced and inverted repeat-induced posttranscriptional gene silencing, the 2b protein (LS2b) of the subgroup II strain LS-CMV was not as effective. Reducing nuclear accumulation of LS2b by mutating a residue in its nuclear localization sequence had no effect on RNA silencing suppressor activity, while attenuated viral symptoms. Electrophoretic mobility shift assays showed that the sRNA binding of LS2b was weaker and more selective than that of Fny2b. The domain determining the differential sRNA-binding ability was delimited to the putative helix α1 region. Moreover, LS2b mutants that completely lost suppressor activity still retained their weak sRNA-binding ability, suggesting that sRNA binding is not sufficient for LS2b to suppress RNA silencing. Considering the subgroup I strain-encoded 2b proteins that require sRNA-binding ability for the suppression of RNA silencing, we suggest that in addition to binding sRNA, the 2b proteins of subgroup II CMV strains would require extra biological activities to achieve RNA silencing inhibition.
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Affiliation(s)
- Yingying Gao
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Jinrui Yang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Xiaobei Zhang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Aizhong Chen
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Zhouhang Gu
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
| | - Zhiyou Du
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China
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Zhang M, Gong P, Ge L, Chang Z, Cheng X, Zhou X, Wang A, Li F. Nuclear exportin 1 facilitates turnip mosaic virus infection by exporting the sumoylated viral replicase and by repressing plant immunity. THE NEW PHYTOLOGIST 2021; 232:1382-1398. [PMID: 34327705 DOI: 10.1111/nph.17657] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 07/23/2021] [Indexed: 06/13/2023]
Abstract
Exportin 1/XPO1 is an important nuclear export receptor that binds directly to cargo proteins and translocates the cargo proteins to the cytoplasm. To understand XPO1 protein functions during potyvirus infections, we investigated the nuclear export of the NIb protein encoding the RNA-dependent RNA polymerase (RdRp) of turnip mosaic virus (TuMV). Previously, we found that NIb is transported to the nucleus after translation and sumoylated by the sumoylation (small ubiquitin-like modifier) pathway to support viral infection. Here, we report that XPO1 interacts with NIb to facilitate translocation from the nucleus to the viral replication complexes (VRCs) that accumulate in the perinuclear regions of TuMV-infected cells. XPO1 contains two NIb-binding domains that recognize and interact with NIb in the nucleus and in the perinuclear regions, respectively, which facilitates TuMV replication. Moreover, XPO1 is involved in nuclear export of the sumoylated NIb and host factors tagged with SUMO3 that is essential for suppression of plant immunity in the nucleus. Deficiencies of XPO1 in Arabidopsis and Nicotiana benthamiana plants inhibit TuMV replication and infection. These data demonstrate that XPO1 functions as a host factor in TuMV infection by regulating NIb nucleocytoplasmic transport and plant immunity.
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Affiliation(s)
- Mingzhen Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Pan Gong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Linhao Ge
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Zhaoyang Chang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Xiaofei Cheng
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, N5V 4T3, Canada
- College of Agriculture, Northeast Agricultural University, Harbin, Heilongjiang, 150030, China
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, N5V 4T3, Canada
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
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Zhou T, Zhang M, Gong P, Li F, Zhou X. Selective autophagic receptor NbNBR1 prevents NbRFP1-mediated UPS-dependent degradation of βC1 to promote geminivirus infection. PLoS Pathog 2021; 17:e1009956. [PMID: 34570833 PMCID: PMC8496818 DOI: 10.1371/journal.ppat.1009956] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 10/07/2021] [Accepted: 09/13/2021] [Indexed: 01/03/2023] Open
Abstract
Autophagy is an evolutionarily conserved, lysosomal/vacuolar degradation mechanism that targets cell organelles and macromolecules. Autophagy and autophagy-related genes have been studied for their antiviral and pro-viral roles in virus-infected plants. Here, we demonstrate the pro-viral role of a selective autophagic receptor NbNBR1 in geminivirus-infected Nicotiana benthamiana plants. The βC1 protein encoded by tomato yellow leaf curl China betasatellite (TYLCCNB) that is associated with tomato yellow leaf curl China virus (TYLCCNV) enhanced the expression level of NbNBR1. Then NbNBR1 interacted with βC1 to form cytoplasmic granules. Interaction of NbNBR1 with βC1 could prevent degradation of βC1 by the NbRFP1, an E3 ligase. Overexpression of NbNBR1 in N. benthamiana plants increased βC1 accumulation and promoted virus infection. In contrast, silencing or knocking out NbNBR1 expression in N. benthamiana suppressed βC1 accumulation and inhibited virus infection. A single amino acid substitution in βC1 (βC1K4A) abolished its interaction with NbNBR1, leading to a reduced level of βC1K4A. The TYLCCNV/TYLCCNBK4A mutant virus caused milder disease symptoms and accumulated much less viral genomic DNAs in the infected plants. Collectively, the results presented here show how a viral satellite-encoded protein hijacks host autophagic receptor NbNBR1 to form cytoplasmic granules to protect itself from NbRFP1-mediated degradation and facilitate viral infection.
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Affiliation(s)
- Tingting Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mingzhen Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Pan Gong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xueping Zhou
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Ghosh D, M M, Chakraborty S. Impact of viral silencing suppressors on plant viral synergism: a global agro-economic concern. Appl Microbiol Biotechnol 2021; 105:6301-6313. [PMID: 34423406 DOI: 10.1007/s00253-021-11483-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/27/2022]
Abstract
Plant viruses are known for their devastating impact on global agriculture. These intracellular biotrophic pathogens can infect a wide variety of plant hosts all over the world. The synergistic association of plant viruses makes the situation more alarming. It usually promotes the replication, movement, and transmission of either or both the coexisting synergistic viral partners. Although plants elicit a robust antiviral immune reaction, including gene silencing, to limit these infamous invaders, viruses counter it by encoding viral suppressors of RNA silencing (VSRs). Growing evidence also suggests that VSRs play a driving role in mediating the plant viral synergism. This review briefly discusses the evil impacts of mixed infections, especially synergism, and then comprehensively describes the emerging roles of VSRs in mediating the synergistic association of plant viruses. KEY POINTS: • Synergistic associations of plant viruses have devastating impacts on global agriculture. • Viral suppressors of RNA silencing (VSRs) play key roles in driving plant viral synergism.
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Affiliation(s)
- Dibyendu Ghosh
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Malavika M
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
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Gnanasekaran P, Gupta N, Ponnusamy K, Chakraborty S. Geminivirus Betasatellite-Encoded βC1 Protein Exhibits Novel ATP Hydrolysis Activity That Influences Its DNA-Binding Activity and Viral Pathogenesis. J Virol 2021; 95:e0047521. [PMID: 34132576 PMCID: PMC8354231 DOI: 10.1128/jvi.00475-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/09/2021] [Indexed: 11/20/2022] Open
Abstract
Plant virus satellites are maintained by their associated helper viruses, and satellites influence viral pathogenesis. Diseases caused by geminivirus-betasatellite complexes can become epidemics and therefore have become a threat to economically important crops across the world. Here, we identified a novel molecular function of the betasatellite-encoded pathogenicity determinant βC1. The tomato leaf curl Patna betasatellite (ToLCPaB)-encoded βC1 protein was found to exhibit novel ATPase activity in the presence of the divalent metal ion cofactor MgCl2. Moreover, ATPase activity was confirmed to be ubiquitously displayed by βC1 proteins encoded by diverse betasatellites. Mutational and sequence analysis showed that conserved lysine/arginine residues at positions 49/50 and 91 of βC1 proteins are essential for their ATPase activity. Biochemical studies revealed that the DNA-binding activity of the βC1 protein was interfered with by the binding of ATP to the protein. Mutating arginine 91 of βC1 to alanine reduced its DNA-binding activity. The results of docking studies provided evidence for an overlap of the ATP-binding and DNA-binding regions of βC1 and for the importance of arginine 91 for both ATP-binding and DNA-binding activities. A mutant betasatellite with a specifically βC1-ATPase dominant negative mutation was found to induce symptoms on Nicotiana benthamiana plants similar to those induced by wild-type betasatellite infection. The ATPase function of βC1 was found to be negatively associated with geminivirus-betasatellite DNA accumulation, despite the positive influence of this ATPase function on the accumulation of replication-associated protein (Rep) and βC1 transcripts. IMPORTANCE Most satellites influence the pathogenesis of their helper viruses. Here, we characterized the novel molecular function of βC1, a nonstructural pathogenicity determinant protein encoded by a betasatellite. We demonstrated the display of ATPase activity by this βC1 protein. Additionally, we confirmed the ubiquitous display of ATPase activity by βC1 proteins encoded by diverse betasatellites. The lysine/arginine residues conserved at positions 49 and 91 of βC1 were found to be crucial for its ATPase function. DNA-binding activity of βC1 was found to be reduced in the presence of ATP. Inhibition of ATPase activity of βC1 in the presence of an excess concentration of cold ATP, GTP, CTP, or UTP suggested that the purified βC1 can also hydrolyze other cellular nucleoside triphosphates (NTPs) besides ATP in vitro. These results established the importance of the ATPase and DNA-binding activities of the βC1 protein in regulating geminivirus-betasatellite DNA accumulation in the infected plant cell.
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Affiliation(s)
- Prabu Gnanasekaran
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru Universitygrid.10706.30, New Delhi, India
| | - Neha Gupta
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru Universitygrid.10706.30, New Delhi, India
| | | | - Supriya Chakraborty
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru Universitygrid.10706.30, New Delhi, India
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Genome-wide approaches for the identification of markers and genes associated with sugarcane yellow leaf virus resistance. Sci Rep 2021; 11:15730. [PMID: 34344928 PMCID: PMC8333424 DOI: 10.1038/s41598-021-95116-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 07/19/2021] [Indexed: 11/10/2022] Open
Abstract
Sugarcane yellow leaf (SCYL), caused by the sugarcane yellow leaf virus (SCYLV) is a major disease affecting sugarcane, a leading sugar and energy crop. Despite damages caused by SCYLV, the genetic base of resistance to this virus remains largely unknown. Several methodologies have arisen to identify molecular markers associated with SCYLV resistance, which are crucial for marker-assisted selection and understanding response mechanisms to this virus. We investigated the genetic base of SCYLV resistance using dominant and codominant markers and genotypes of interest for sugarcane breeding. A sugarcane panel inoculated with SCYLV was analyzed for SCYL symptoms, and viral titer was estimated by RT-qPCR. This panel was genotyped with 662 dominant markers and 70,888 SNPs and indels with allele proportion information. We used polyploid-adapted genome-wide association analyses and machine-learning algorithms coupled with feature selection methods to establish marker-trait associations. While each approach identified unique marker sets associated with phenotypes, convergences were observed between them and demonstrated their complementarity. Lastly, we annotated these markers, identifying genes encoding emblematic participants in virus resistance mechanisms and previously unreported candidates involved in viral responses. Our approach could accelerate sugarcane breeding targeting SCYLV resistance and facilitate studies on biological processes leading to this trait.
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Gupta N, Reddy K, Bhattacharyya D, Chakraborty✉ S. Plant responses to geminivirus infection: guardians of the plant immunity. Virol J 2021; 18:143. [PMID: 34243802 PMCID: PMC8268416 DOI: 10.1186/s12985-021-01612-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/29/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Geminiviruses are circular, single-stranded viruses responsible for enormous crop loss worldwide. Rapid expansion of geminivirus diversity outweighs the continuous effort to control its spread. Geminiviruses channelize the host cell machinery in their favour by manipulating the gene expression, cell signalling, protein turnover, and metabolic reprogramming of plants. As a response to viral infection, plants have evolved to deploy various strategies to subvert the virus invasion and reinstate cellular homeostasis. MAIN BODY Numerous reports exploring various aspects of plant-geminivirus interaction portray the subtlety and flexibility of the host-pathogen dynamics. To leverage this pool of knowledge towards raising antiviral resistance in host plants, a comprehensive account of plant's defence response against geminiviruses is required. This review discusses the current knowledge of plant's antiviral responses exerted to geminivirus in the light of resistance mechanisms and the innate genetic factors contributing to the defence. We have revisited the defence pathways involving transcriptional and post-transcriptional gene silencing, ubiquitin-proteasomal degradation pathway, protein kinase signalling cascades, autophagy, and hypersensitive responses. In addition, geminivirus-induced phytohormonal fluctuations, the subsequent alterations in primary and secondary metabolites, and their impact on pathogenesis along with the recent advancements of CRISPR-Cas9 technique in generating the geminivirus resistance in plants have been discussed. CONCLUSIONS Considering the rapid development in the field of plant-virus interaction, this review provides a timely and comprehensive account of molecular nuances that define the course of geminivirus infection and can be exploited in generating virus-resistant plants to control global agricultural damage.
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Affiliation(s)
- Neha Gupta
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Kishorekumar Reddy
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Dhriti Bhattacharyya
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Supriya Chakraborty✉
- Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
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Transcriptional Responses of Sclerotinia sclerotiorum to the Infection by SsHADV-1. J Fungi (Basel) 2021; 7:jof7070493. [PMID: 34206246 PMCID: PMC8303302 DOI: 10.3390/jof7070493] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 06/14/2021] [Accepted: 06/16/2021] [Indexed: 12/13/2022] Open
Abstract
The infection by a single-stranded DNA virus, Sclerotinia sclerotiorum hypovirulence-associated DNA virus 1 (SsHADV-1), causes hypovirulence, a reduced growth rate, and other colony morphological changes in its host Sclerotinia sclerotiorum strain DT-8. However, the mechanisms of the decline are still unclear. Using digital RNA sequencing, a transcriptome analysis was conducted to elucidate the phenotype-related genes with expression changes in response to SsHADV-1 infection. A total of 3110 S. sclerotiorum differentially expressed genes (DEGs) were detected during SsHADV-1 infection, 1741 of which were up-regulated, and 1369 were down-regulated. The identified DEGs were involved in several important pathways. DNA replication, DNA damage response, carbohydrate and lipid metabolism, ribosomal assembly, and translation were the affected categories in S. sclerotiorum upon SsHADV-1 infection. Moreover, the infection of SsHADV-1 also suppressed the expression of antiviral RNA silencing and virulence factor genes. These results provide further detailed insights into the effects of SsHADV-1 infection on the whole genome transcription in S. sclerotiorum.
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Veluthambi K, Sunitha S. Targets and Mechanisms of Geminivirus Silencing Suppressor Protein AC2. Front Microbiol 2021; 12:645419. [PMID: 33897657 PMCID: PMC8062710 DOI: 10.3389/fmicb.2021.645419] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/10/2021] [Indexed: 11/13/2022] Open
Abstract
Geminiviruses are plant DNA viruses that infect a wide range of plant species and cause significant losses to economically important food and fiber crops. The single-stranded geminiviral genome encodes a small number of proteins which act in an orchestrated manner to infect the host. The fewer proteins encoded by the virus are multifunctional, a mechanism uniquely evolved by the viruses to balance the genome-constraint. The host-mediated resistance against incoming virus includes post-transcriptional gene silencing, transcriptional gene silencing, and expression of defense responsive genes and other cellular regulatory genes. The pathogenicity property of a geminiviral protein is linked to its ability to suppress the host-mediated defense mechanism. This review discusses what is currently known about the targets and mechanism of the viral suppressor AC2/AL2/transcriptional activator protein (TrAP) and explore the biotechnological applications of AC2.
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Affiliation(s)
- Karuppannan Veluthambi
- Department of Plant Biotechnology, School of Biotechnology, Madurai Kamaraj University, Madurai, India
| | - Sukumaran Sunitha
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States
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48
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Teixeira RM, Ferreira MA, Raimundo GAS, Fontes EPB. Geminiviral Triggers and Suppressors of Plant Antiviral Immunity. Microorganisms 2021; 9:microorganisms9040775. [PMID: 33917649 PMCID: PMC8067988 DOI: 10.3390/microorganisms9040775] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/26/2021] [Accepted: 03/26/2021] [Indexed: 12/19/2022] Open
Abstract
Geminiviruses are circular single-stranded DNA plant viruses encapsidated into geminate virion particles, which infect many crops and vegetables and, hence, represent significant agricultural constraints worldwide. To maintain their broad-range host spectrum and establish productive infection, the geminiviruses must circumvent a potent plant antiviral immune system, which consists of a multilayered perception system represented by RNA interference sensors and effectors, pattern recognition receptors (PRR), and resistance (R) proteins. This recognition system leads to the activation of conserved defense responses that protect plants against different co-existing viral and nonviral pathogens in nature. Furthermore, a specific antiviral cell surface receptor signaling is activated at the onset of geminivirus infection to suppress global translation. This review highlighted these layers of virus perception and host defenses and the mechanisms developed by geminiviruses to overcome the plant antiviral immunity mechanisms.
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49
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Yan Z, Wolters AMA, Navas-Castillo J, Bai Y. The Global Dimension of Tomato Yellow Leaf Curl Disease: Current Status and Breeding Perspectives. Microorganisms 2021; 9:740. [PMID: 33916319 PMCID: PMC8066563 DOI: 10.3390/microorganisms9040740] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 12/20/2022] Open
Abstract
Tomato yellow leaf curl disease (TYLCD) caused by tomato yellow leaf curl virus (TYLCV) and a group of related begomoviruses is an important disease which in recent years has caused serious economic problems in tomato (Solanum lycopersicum) production worldwide. Spreading of the vectors, whiteflies of the Bemisia tabaci complex, has been responsible for many TYLCD outbreaks. In this review, we summarize the current knowledge of TYLCV and TYLV-like begomoviruses and the driving forces of the increasing global significance through rapid evolution of begomovirus variants, mixed infection in the field, association with betasatellites and host range expansion. Breeding for host plant resistance is considered as one of the most promising and sustainable methods in controlling TYLCD. Resistance to TYLCD was found in several wild relatives of tomato from which six TYLCV resistance genes (Ty-1 to Ty-6) have been identified. Currently, Ty-1 and Ty-3 are the primary resistance genes widely used in tomato breeding programs. Ty-2 is also exploited commercially either alone or in combination with other Ty-genes (i.e., Ty-1, Ty-3 or ty-5). Additionally, screening of a large collection of wild tomato species has resulted in the identification of novel TYLCD resistance sources. In this review, we focus on genetic resources used to date in breeding for TYLCVD resistance. For future breeding strategies, we discuss several leads in order to make full use of the naturally occurring and engineered resistance to mount a broad-spectrum and sustainable begomovirus resistance.
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Affiliation(s)
- Zhe Yan
- Plant Breeding, Wageningen University & Research, P.O. Box 386, 6700 AJ Wageningen, The Netherlands; (Z.Y.); (A.-M.A.W.)
| | - Anne-Marie A. Wolters
- Plant Breeding, Wageningen University & Research, P.O. Box 386, 6700 AJ Wageningen, The Netherlands; (Z.Y.); (A.-M.A.W.)
| | - Jesús Navas-Castillo
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora”, Consejo Superior de Investigaciones Científicas Universidad de Málaga (IHSM-CSIC-UMA), Avenida Dr. Weinberg s/n, 29750 Algarrobo-Costa, Málaga, Spain;
| | - Yuling Bai
- Plant Breeding, Wageningen University & Research, P.O. Box 386, 6700 AJ Wageningen, The Netherlands; (Z.Y.); (A.-M.A.W.)
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Identification and Characterization of Plant-Interacting Targets of Tomato Spotted Wilt Virus Silencing Suppressor. Pathogens 2021; 10:pathogens10010027. [PMID: 33401462 PMCID: PMC7823891 DOI: 10.3390/pathogens10010027] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/09/2020] [Accepted: 11/16/2020] [Indexed: 02/02/2023] Open
Abstract
Tomato spotted wilt virus (TSWV; species Tomato spotted wilt orthotospovirus) is an economically important plant virus that infects multiple horticultural crops on a global scale. TSWV encodes a non-structural protein NSs that acts as a suppressor of host RNA silencing machinery during infection. Despite extensive structural and functional analyses having been carried out on TSWV NSs, its protein-interacting targets in host plants are still largely unknown. Here, we systemically investigated NSs-interacting proteins in Nicotiana benthamiana via affinity purification and mass spectrometry (AP-MS) analysis. Forty-three TSWV NSs-interacting candidates were identified in N. benthamiana. Gene Ontology (GO) and protein–protein interaction (PPI) network analyses were carried out on their closest homologs in tobacco (Nicotiana tabacum), tomatoes (Solanum lycopersicum) and Arabidopsis (Arabidopsis thaliana). The results showed that NSs preferentially interacts with plant defense-related proteins such as calmodulin (CaM), importin, carbonic anhydrase and two heat shock proteins (HSPs): HSP70 and HSP90. As two major nodes in the PPI network, CaM and importin subunit α were selected for the further verification of their interactions with NSs via yeast two-hybrid (Y2H) screening. Our work suggests that the downstream signaling, transportation and/or metabolic pathways of host-NSs-interacting proteins may play critical roles in NSs-facilitated TSWV infection.
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