3. イネのコパリルニリン酸合成酵素遺伝子について

概要

論文の詳細を見る
We have isolated two cDNAs, OsCyc1 and OsCyc2,encoding diterpene cyclases that are involved in phytoalexin biosynthesis from rice (Oryza sativa L. cv. Nipponbare) leaves. Oscyc1 and OsCyc2 encode syn-copalyl diphosphate (CDP) synthase and ent-CDP synthase, respectively. In this report, we isolated a cDNA, OsCPS, encoding ent-CDP synthase responsible for the biosynthesis of gibberellins (GAs) in rice. It has been shown that a loss-of-function mutation in the OsCPS gene results in a GA-deficient phenotype. Using a bacterial expression system, it was suggested that the translated product of OsCPS could convert geranylgeranyl diphosphate into ent-CDP. Transcript levels of OsCPS did not change in rice leaves after ultra-violet (UV) irradiation, whereas those of OsCyc1 and OsCyc2 drastically increased in response to UV treatment. These results suggest that two ent-CDP synthases, one for the biosynthesis of GAs and the other for phytoalexins, are encoded by two distinct genes in rice.
植物化学調節学会の論文
2003-10-10