Abstract
Nicotianamine synthase (NAS) and nicotianamine aminotransferase (NAAT) are the enzymes in the biosynthetic pathway of mugineic acid family phytosiderophores (MAs). MAs are metal chelators biosynthesized in graminaceous plants, and NA, a chelator of metals, is ubiquitously present in higher plants. NA is essential for reproductive growth, and the NA-less tobacco was sterile (Takahashi et al., 2003, 15, 1263-1280, Plant Cell).
In this study, we investigated NAS gene expression in inflorescences and seeds of Arabidopsis using the reporter gene (GUS) to illuminate the roles of NA at reproductive stage in dicot. Similarly, to illuminate the role of NA and MAs at reproductive stage in monocot, we investigated the gene expression of NAS and NAAT in inflorescences and seeds of rice. The results indicated that NA and MAs play a critical role in embryogenesis in addition to a role in metal translocation to inflorescence and seeds.
