Abstract
Barley is one of the most aluminum sensitive species in the small cereal grains. However, a wide genetic variation in Al tolerance has been observed. It was reported that Al tolerance was tightly linked to the Al-induced citrate secretion from the roots. To identify the mechanisms leading to Al-induced citrate secretion, gene expression patterns of Al-tolerant cultivar (Murasakimochi) and -sensitive cultivar (Morex) were investigated using a barley genechip containing 22840 probes. Total RNA was extracted from root tips (1cm) exposed to 0 or 5 μM Al for 6 h. Results show that 149 and 211 genes were up-regulated more than 2-fold by Al, respectively, in Murasakimochi and Morex. In Murasakimochi, genes related to transporter were not induced by Al, but some transporter-related genes show high and constitutive expression pattern compared to Morex. Time and tissue-dependent expression of these genes are now under investigation.
