Tomato spotted wilt virus NSs protein supports infection and systemic movement of a potyvirus and is a symptom determinant

Hernan Garcia-Ruiz, Sergio M. Gabriel Peralta, Patricia A. Harte-Maxwell

Research output: Contribution to journalArticle

7 Scopus citations

Abstract

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.

Original languageEnglish (US)
Article number129
JournalViruses
Volume10
Issue number3
DOIs
StatePublished - Mar 14 2018

Keywords

  • Antiviral defense
  • Gene silencing
  • HC-Pro
  • NSs
  • Orthotospovirus
  • Silencing suppression
  • Tomato spotted wilt virus
  • Turnip mosaic virus
  • Virus movement
  • Virus resistance

ASJC Scopus subject areas

  • Infectious Diseases
  • Virology

Fingerprint Dive into the research topics of 'Tomato spotted wilt virus NSs protein supports infection and systemic movement of a potyvirus and is a symptom determinant'. Together they form a unique fingerprint.

  • Cite this