TRANSCRIPTIONAL ANALYSIS OF RIBOSOMAL PROTEIN L3 (RPL3) GENES UNDER FUSARIUM HEAD BLIGHT INFECTION IN WHEAT

Deoxynivalenol (DON) is a major mycotoxin produced by the fungus Fusarium graminearum during infection and is known to be harmful to both animal and human health. DON is believed to act as a virulence factor in fungal pathogenesis by inhibiting eukaryotic protein synthesis. The putative site of action of DON is 60s ribosomal protein L3 (RPL3). Previously, single amino acid changes in RPL3 conferring DON resistance have been described in yeast. Sequence characterization of six wheat genes encoding RPL3 has shown that there is no amino acid alteration between resistant and susceptible cultivars. The main goal of this study, was to determine any induced changes in transcriptional levels of RPL3 (A and B type) genes under stress conditions caused by Fusarium Head Blight (FHB) in wheat. In order to detect expression levels of RPL3 genes, we extracted RNA from both inoculated and non-inoculated spikes of sensitive and tolerant cultivars, during 1, 3 and 7 days post-infection. Quantitative RT-PCRs were performed with A and B type-specific RPL3 primers to detect the expression differences. Primary data indicated a decrease in the genes expression level in Sumai3 and Falat cultivars 24 hours post-infection. On the other hand, increased level of RPL3A transcript in Frontana 7 days post-infection may reveal the role of this specific protein in inducing the resistance in this cultivar.