ISOLATION OF CDNA CLONES FOR GENES THAT ARE SPECIFICALLY EXPRESSED INTHE RICE EMBRYO

We isolated thirty-eight cDNA clones representing genes expressed in t he rice embryo by differential screening of a cDNA library made with p oly(A) RNA from embryos at the stage of 10-days after pollination. Eig hteen cDNA clones displayed either a significant nucleic acid or amino acid sequence similarity to sequences known in the GenBank, i.e., two rice oleosins, four globulin or glutelin-like proteins, two ABA respo nse proteins, two LEA-like proteins, one trypsin inhibitor, one metall othionein-like protein, one protein kinase, one leucine-zipper contain ing protein, one proline-rich protein, and three genes of unknown func tion. Experimental results indicated the presence of redundant cDNA cl ones for genes that produced an abundant amount of mRNAs in the embryo . RNA slat blot hybridization demonstrated the embryo-specific express ion for thirty-seven cDNA clones. The majority of the identified cDNAs had not been known in rice. Results in this study contribute toward t he on-going attempt to isolate embryo-specific and novel genes in rice .