Transformants of some rice full-length cDNAs vs wild-type Col-0

We generated more than 23,000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt-tolerance, UV signaling, high light tolerance, and heat stress tolerance. Since we isolated 6 genes (AK069096, AK073112, AK073675, AK065297, AK102323 and AK073210) causing an increase in the abundance of metabolites or pigments detected by absorption data, we investigated the expression profiles in transgenic plants by using microarray analysis. Expression of the genes encoding chalcone synthase and dihydroflavonol-4-reductase was increased in all 6 cDNA transformants. These results indicate that an increase in expression of the genes encoding flavonoid biosynthesis enzymes caused an accumulation of pigments in these 6 transformants. Total RNA was isolated from aerial parts of re-transformants of some rice cDNAs and wild type using an RNAqueous Kit (Ambion, Inc, USA).