Self-interaction of Tomato spotted wilt virus NSs protein enhances gene silencing suppressor activity, but is dispensable as avirulence determinant on pepper

• Published in: Biologia plantarum Vol. 67; no. 1; pp. 105 - 113
• Main Authors: ALMÁSI, A., NEMES, K., SÁRAY, R., GELLÉRT, Á., INCZE, N., VÁGI, P., BADICS, E., SOÓS, V., SALÁNKI, K.
• Format: Journal Article
• Language: English
• Published: Institute of Experimental Botany of the Czech Academy of Sciences 01-01-2023
• Subjects: avirulence determinant; hypersensitive reaction; nss protein; self-interaction; tomato spotted wilt virus; viral suppressor of rna silencing
• ISSN: 0006-3134; 1573-8264
• DOI: 10.32615/bp.2023.010

Tomato spotted wilt virus (TSWV) has significant economic impact on horticulture worldwide. One of the five proteins encoded by TSWV genome is the multifunctional NSs protein, which is a viral suppressor of RNA silencing (VSR) besides functioning as the effector of Tsw resistance gene in resistant pepper cultivars. In this study we demonstrate the in vivo self-interaction of NSs protein using bimolecular fluorescence complementation and yeast two-hybrid assays, and propose that a highly charged alpha helix located at the second half of the protein is required for self-interaction. Furthermore, we confirmed that self-interaction is not required for its effector function on pepper. Moreover, self-interaction is dispensable for gene silencing suppressor activity, although it enhances the suppression efficiency.