Identification of differentially expressed proteins in wheat after benzothiadiazole treatment

The systemic acquired resistance (SAR) mechanism is stimulated by biological and chemical agents in response to pathogen infection as a part of the innate immunity response system of plants. The externally applied synthetic chemical, benzo-(1,2,3)-thiadiazole-7-carbothioic acid-S-methyl ester (BTH), is also known to induce a SAR response in plants. Studies identifying genes induced or suppressed by BTH are limited. Only few genes responding to BTH are determined. The focus of this preliminary study is to identify the gene products affected by BTH in wheat. A 2D-polyacrylamide gel electrophoresis (PAGE) analysis was carried out with BTH treated Triticum aestivum cv. Gerek-79 and mock treated samples. Following 2D-PAGE image analysis, the selected differentially expressed protein spots were identified by nanoLC-ESI-MS/MS. Among the 26 protein spots distinguished, five were found to be increased upon BTH treatment, another set of seven spots were absent in the control sample.Thus, they were apparent only in the gel of the BTH treated sample (+BTH), whereas five protein spots disappeared in the gel of the BTH treated plants (-BTH). Up-regulation of some proteins such as OEE2 (oxygen evolving enhancer protein) and COR (cold-responsive) LEA (late embryogenesis abundant)/RAB (responsive to abscisic acid, ABA) and down-regulation of some proteins such as RuBisCo LSU (large subunit), fructose 1, 6-biphosphate aldolase (AldP), methyl binding domain protein 6 (MBD6), and 3-isopropylmalate dehydrogenase are shown for the first time in BTH treatment of wheat.