Abstract
We attempted to analyze gene expression in the absence and presence of nitrogen using a Lotus japonicus Gifu B-129. For the gene expression analysis by RT-PCR, we used 12 transporter genes of Lotus japonicus provided by Kazusa DNA Research Institute. Namely, plants were grown on nitrogen-free medium for 60 days and total RNA was extracted from the roots, stems and leaves for RT-PCR, respectively. As a result, of the 12 genes, 6 genes exhibited constitutive expression in roots, stems and leaves, respectively. Moreover, of remaining 6 genes, each of 2 genes was specifically expressed in leaves and roots. In contrast, despite nitrogen-supplement, 6 genes exhibited constitutive expression in roots, stems and leaves, respectively. However, of remaining 6 genes, the expression level of 4 genes was suppressed within 24 hrs in roots and leaves in the presence of nitrogen. These genes are highly identical to amino acid and nitrate transporters.
