Multi-Layered Screening Method Identification Of Flavonoid-Specific Genes, Using Transgenic Rice

We used microarray analysis to identify 6 730 genes potentially related to flavonoid biosynthesis by comparing their expression between high- and low-flavonoid cultivars at three stages of seed development. The genes included 167 transcription factors, 104 pathway-network genes, and I 207 potential orthologs with flavonoid-related functions. We compared the transcription factors, pathway genes, and orthologs and identified seven conserved hypothetical genes that are involved in flavonoid biosynthesis. We then verified the seven genes experimentally by reverse transcription polymerase chain reaction. These conserved genes most likely play regulatory roles either in rice-flavonoid production or flavonoid signaling during seed development. Our study illustrates the effectiveness of microarray analysis followed by multi-layered screening for the identification of flavonoid-related genes in rice.