Document Type: Research Paper
Departement of Biology, Faculty of Science, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran.
Department of Molecular Plant Physiology, Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Trehalose is the non-reducing alpha-alpha-1, 1-linked glucose disaccharide. The biosynthesis
precursor of trehalose, trehalose-6-phosphate (T6P), is essential for plant development, growth,
carbon utilization and alters photosynthetic capacity but its mode of action is not understood. In the
current research, 6 days old seedlings of Arabidopsis thaliana (Columbia ecotype) were grown in
liquid culture containing 100 mM trehalose, sorbitol or sucrose for 24 hours. Changes in the genes
expression patterns were studied by cDNA microarray analysis. In sucrose treatment expression of
1745 genes was significantly changed. But trehalose changed significantly the expression of only 162
genes compared to sorbitol after 24h treatment. Gene expressions profiles revealed that 100 mM
trehalose altered 5% of the genes which are changed by 100 mM sucrose. Statistical analysis showed
that only 4 genes which are induced by trehalose repressed by sucrose. Exogenous trehalose treatment
did not down-regulate the expression of carbon catabolite genes, but up-regulates a specific
combination of genes known from biotic stress responses. Trehalose induced gene expression
responses related to ROS and secondary metabolism activation. The expression profile shows
particularly up-regulation (8-fold) of a glutathione transferase (GST22) under trehalose but not
sucrose. Also, trehalose treatment induced expression of the JA and ethylene signaling pathways
factors. These findings revealed that trehalose or its precursor, T6P, are important in gene expression
regulation of plants.