Study : Constitutive activation of the receptor-like kinase NIK impairs translation and confers tolerance to begomovirus infection
Constitutive activation of the receptor-like kinase NIK impairs translation and confers tolerance to begomovirus infection
To generate an efficient defense against begomovirus, we modulated the activity of the immune defense receptor NIK (NSP-Interacting Kinase) in tomato plants; NIK is a virulence target of the begomovirus NSP during infection. Replacing threonine-474 with aspartate (T474D) within the kinase activation loop promoted the constitutive activation of NIK-mediated defenses. This activation resulted in the down-regulation of translation-related genes and the suppression of global translation in T474D-overexpressing tomato lines. We also found that T474D-induced defense-related transcripts were associated with polysomes and immune proteins, which accumulated to detectable levels in T474D leaves. Consistent with these findings, T474D transgenic lines were tolerant to the tomato-infecting begomoviruses ToYSV and ToSRV. We propose that NIK mediates an anti-viral response via translation suppression and immune system induction. Overall design: Global variation on gene expression induced by NIK expression and virus infection using total RNA from mock-inoculated and ToYSV-infected tomato wild-type plants, mock-inoculated and infected 35S::NIK1-4 overexpressing lines and mock-inoculated and infected 35S::T474D overexpressing lines. File map_itag23.csv correlates the ITAG 2.3 cDNA ID with the 21 bp reads in file Profiles_with_differential_expressions.csv.