transformation of tobacco (nicotiana tobacum) plantswith a pbi121: atexpa1 construct

expansin proteins are a type of cell-wall loosening proteins which able to cell wall expansion in ph-dependent manure without hydrolyze of main cell wall structures. the arabidopsis expa1 exhibit guard cell specific expression and trigger the stomatal movements. the objectives of this study were to transfer the atexpa1 gene into tobacco plants and evaluate their phonotypic effects on transformed plants. for transformation of tobacco, the agro-infection method was selected. the activity of transferred gene was confirmed with rt-pcr. obtained results showed that the guard cells of transgenic plants incurred an irreversibly extension which induced by light and subsequently cell acidification, resulting in loss of plant cellular water and wilting in plants. these results indicate that atexpa1 gene is a cell-guard associated gene and may indirectly involve in regulation of cellular water in different environmental conditions.