Macro-array Approaches to Identify Expression Characteristics of Putative AP2/EREBP Genes of Orzya sativa

AP2/ethylene responsive-element binding proteins (EREBPs) comprise a superfamily of AP2/EREBP domain-containing transcription factors that exist extensively in plants. They are involved in plant development and stress responses. An estimated 150 AP2/EREBP genes exist in Orzya sativa; however, most have not been characterized. To investigate the gene expression profile at the transcriptional level, we retrieved and amplified 32 putative AP2/EREBP genes from the rice genomic database on the basis of AP2/EREBP domain sequencing from Arabidopsis. The sequences of these putative genes were amplified by PCR for macro-array analysis. Results of hybridization of these putative genes with probes from different organs of O. sativa suggested that the level of expression of AP2 subfamily members differed; however, most were expressed consistently in different organs of O. sativa. On the contrary, most of the putative EREBPs were expressed intensively in young roots and mature leaves but much less in young buds and young leaves. The patterns of expression of these genes may be related to their functions.