Microarray Analysis Of Rice Seed CDNAs And Characterization Of Two Embryo-specific Genes RS2 And RS6

For identification of genes involved in development in the model cereal rice,we have constructed a cDNA library of rice (Oryza sativa . Zhong Hua 11)seeds at 9-12 days after pollination(DAP). A method designated cDNA microarray was used for the hybridization of differential screening. With the BLAST search in the GenBank database, there are 157 cDNA clones that share significant sequence similarities to seed storage proteins, embryogenesis or embryo-specific proteins and 115 cDNA clones that encode unknown proteins. Two genes were isolated and characterized. RS2 encodes a embryogenesis protein, whereas RS6 corresponds to the embryo-specific globulin-like protein. In RNA gel blot analysis showed that both RS2 and RS6 are expressed highly in 10 DAP embryo and throughout the endosperm from 2 to 20 DAP, while RS2 is still expressed lowly in roots, leaves, spike and the seeds at 1 DAP. To further characterize their biological function, antisense constructs of RS2 and RS6 were introduced into rice by means of an Agrobacteriunrmediated transformation. We have got some anti-RS2 and anti~JfS6 transgenic plants respectively. Now the further work is undergoing.