ISOLATION OF GENE TRANSCRIPTS DURING AGARWOOD RESIN ACCUMULATING BY SUBTRACTIVE HYBRIDIZATION TECHNIQUE

Resin production of Aquilaria species, one of the plant defense mechanisms, is triggered by external stimuli such as chemical and biological treatment. However, mechanism of gene expression during resin accumulation has been fully understood. This study acquired subtractive hybridization technique (SH) to find genes involved in the mechanism. Based on sequence similarity, most genes were identified as fungal genes. Only one sequence was predicted to be a plant gene which was tropinone reductase (TR) gene containing two important motifs, TGxxxGxG motif and YxxxK motif. A.crassna TR could be categorized into short-chain dehydrogenases/reductases (SDRs) family. There is no evidence suggesting a relationship between TR and resin production in agarwood, which should be studied further. Moreover, the result of dot blot hybridization indicated that three unkown sequences gave positive dots, which were likely to be unidentified plant genes. Therefore, these three unknown sequences should be given gene annotation in the future.