Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant
Plant viruses are inducers and targets of antiviral RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressor proteins that interfere with antiviral RNA silencing. The NSs protein is an RNA silencing suppressor in orthotospoviruses, such as the tomato spotted wilt vi...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-03-01
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| Series: | Viruses |
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| Online Access: | http://www.mdpi.com/1999-4915/10/3/129 |
| _version_ | 1818517839147958272 |
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| author | Hernan Garcia-Ruiz Sergio M. Gabriel Peralta Patricia A. Harte-Maxwell |
| author_facet | Hernan Garcia-Ruiz Sergio M. Gabriel Peralta Patricia A. Harte-Maxwell |
| author_sort | Hernan Garcia-Ruiz |
| collection | DOAJ |
| description | Plant viruses are inducers and targets of antiviral RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressor proteins that interfere with antiviral RNA silencing. The NSs protein is an RNA silencing suppressor in orthotospoviruses, such as the tomato spotted wilt virus (TSWV). The mechanism of RNA silencing suppression by NSs and its role in virus infection and movement are poorly understood. Here, we cloned and tagged TSWV NSs and expressed it from a GFP-tagged turnip mosaic virus (TuMV-GFP) carrying either a wild-type or suppressor-deficient (AS9) helper component proteinase (HC-Pro). When expressed in cis, NSs restored pathogenicity and promoted systemic infection of suppressor-deficient TuMV-AS9-GFP in Nicotiana benthamiana and Arabidopsis thaliana. Inactivating mutations were introduced in NSs RNA-binding domain one. A genetic analysis with active and suppressor-deficient NSs, in combination with wild-type and mutant plants lacking essential components of the RNA silencing machinery, showed that the NSs insert is stable when expressed from a potyvirus. NSs can functionally replace potyviral HC-Pro, condition virus susceptibility, and promote systemic infection and symptom development by suppressing antiviral RNA silencing through a mechanism that partially overlaps that of potyviral HC-Pro. The results presented provide new insight into the mechanism of silencing suppression by NSs and its effect on virus infection. |
| first_indexed | 2024-12-11T01:01:42Z |
| format | Article |
| id | doaj.art-3fdf43f0aa4a4cac9416f59a662958ea |
| institution | Directory Open Access Journal |
| issn | 1999-4915 |
| language | English |
| last_indexed | 2024-12-11T01:01:42Z |
| publishDate | 2018-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Viruses |
| spelling | doaj.art-3fdf43f0aa4a4cac9416f59a662958ea2022-12-22T01:26:18ZengMDPI AGViruses1999-49152018-03-0110312910.3390/v10030129v10030129Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom DeterminantHernan Garcia-Ruiz0Sergio M. Gabriel Peralta1Patricia A. Harte-Maxwell2Nebraska Center for Virology, Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68503, USANebraska Center for Virology, Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68503, USANebraska Center for Virology, Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68503, USAPlant viruses are inducers and targets of antiviral RNA silencing. To condition susceptibility, most plant viruses encode silencing suppressor proteins that interfere with antiviral RNA silencing. The NSs protein is an RNA silencing suppressor in orthotospoviruses, such as the tomato spotted wilt virus (TSWV). The mechanism of RNA silencing suppression by NSs and its role in virus infection and movement are poorly understood. Here, we cloned and tagged TSWV NSs and expressed it from a GFP-tagged turnip mosaic virus (TuMV-GFP) carrying either a wild-type or suppressor-deficient (AS9) helper component proteinase (HC-Pro). When expressed in cis, NSs restored pathogenicity and promoted systemic infection of suppressor-deficient TuMV-AS9-GFP in Nicotiana benthamiana and Arabidopsis thaliana. Inactivating mutations were introduced in NSs RNA-binding domain one. A genetic analysis with active and suppressor-deficient NSs, in combination with wild-type and mutant plants lacking essential components of the RNA silencing machinery, showed that the NSs insert is stable when expressed from a potyvirus. NSs can functionally replace potyviral HC-Pro, condition virus susceptibility, and promote systemic infection and symptom development by suppressing antiviral RNA silencing through a mechanism that partially overlaps that of potyviral HC-Pro. The results presented provide new insight into the mechanism of silencing suppression by NSs and its effect on virus infection.http://www.mdpi.com/1999-4915/10/3/129virus movementgene silencingantiviral defensesilencing suppressionvirus resistanceNSsHC-Proorthotospovirustomato spotted wilt virusturnip mosaic virus |
| spellingShingle | Hernan Garcia-Ruiz Sergio M. Gabriel Peralta Patricia A. Harte-Maxwell Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant Viruses virus movement gene silencing antiviral defense silencing suppression virus resistance NSs HC-Pro orthotospovirus tomato spotted wilt virus turnip mosaic virus |
| title | Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant |
| title_full | Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant |
| title_fullStr | Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant |
| title_full_unstemmed | Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant |
| title_short | Tomato Spotted Wilt Virus NSs Protein Supports Infection and Systemic Movement of a Potyvirus and Is a Symptom Determinant |
| title_sort | tomato spotted wilt virus nss protein supports infection and systemic movement of a potyvirus and is a symptom determinant |
| topic | virus movement gene silencing antiviral defense silencing suppression virus resistance NSs HC-Pro orthotospovirus tomato spotted wilt virus turnip mosaic virus |
| url | http://www.mdpi.com/1999-4915/10/3/129 |
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