Transcriptional regulon under the control of LIMYB protein
We showed first that the downstream component of the NIK1/RPL10 antiviral signaling module, LIMYB, which represses translational machinery-related gene expression and translation, also suppresses photosynthetic apparatus-related genes leading to inhibition of the photosynthetic function. The repressing transcriptional activity of LIMYB was the primary determinant for the decrease in electron transport rate, exchange gas parameters, quantum efficiency, and water-use efficiency in the LIMYB-overexpressing lines. The decreased photosynthetic activity was linked to the NIK1 antiviral signaling and stunted growth. Activation of antiviral NIK1 by viral or bacterial PAMPs, or expressing a constitutively activated NIK1 mutant, T474D, inhibited the photosynthetic function in control lines but not in lymyb knockout lines.