Abstract
Rice (Oryza sativa) is the most Al-resistant crop among small-grain cereal crops, but the mechanism underlying its high Al resistance is still poorly understood. Here, we compared transcriptional profile of Al-responsive genes in the root tips and mature zones between the Al-tolerant cultivar (Koshihikari) and a hyper-sensitive mutant star1/als1 (sensitive to Al rhizotoxicity 1) by using Agilent 44K Rice Oligo Microarray. Exposure to 20 μM Al for 6 h caused increased expression (higher than 3 fold) of 786 and 5547 genes including 624 common genes, respectively, in the root tips of WT and the mutant. On the other hand, in the mature root zone, genes up-regulated by Al were 616 and 8676 including 453 common genes, respectively, in the WT and mutant. Genes induced only in the WT may be responsible for Al resistance, while genes induced only in the mutant may be involved in Al-induced damage.
