Abstract
The objective of this study is to perform transcriptomic analyses of rice genes up- or down-regulated by the P-replenishment. cDNA microarray analyses were performed for total RNA of rice plants cultured hydroponically with P treatment (+P, -P, and P-replenishment). The number of genes regulated by P replenishment was about several times higher than that by the -P. OsPI1 gene, which was isolated as the most significant up-regulated gene by -P, was the most significant down-regulated gene by P-replenishment in both roots and shoots. Most of genes down-regulated by P-replenishment were up-regulated by -P, suggesting that their responses were specific in -P conditions. Contrary number of most transcripts up-regulated by the P-replenishment was also larger in P-replenishment than in +P. We considered that the genes up-regulated by P-replenishment played an important role on P acquisition from P deficient plants.
