Metabolic flux analysis of diterpene biosynthesis pathway in rice.
Relative transcript levels of eight rice diterpene cyclases at the branch points of gibberellins and phytoalexins biosynthesis pathway were measured by reverse transcription quantitative PCR. Metabolic flux analysis by the distribution ratio of common substrate showed that UV-irradiation of etiolated rice seedlings decreased the flux for primary metabolism of gibberellins biosynthesis by half (from 62 to 27%) and 41% of geranylgeranyl pyrophosphate was used for induction of pimaradiene intermediate as the major phytoalexin. In comparison, light-illumination used almost all geranylgeranyl pyrophosphate (96%) for gibberellin biosynthesis to stimulate the plant growth and strongly repressed the metabolic flux for phytoalexins biosynthesis.
Chang
Yung-Jin
YJ
School of Agricultural Biotechnology, Seoul National University, 151-742, Seoul, Korea. yjchang@snu.ac.kr
Kim
Bo-Ra
BR
Kim
Soo-Un
SU
D019883:Alkyl and Aryl Transferases / Q000235:genetics / Q000378:metabolism; D019755:Carbon-Carbon Lyases / Q000235:genetics / Q000378:metabolism; D004224:Diterpenes / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000096:biosynthesis; D007535:Isomerases / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D012275:Oryza / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D010936:Plant Extracts / Q000096:biosynthesis; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011106:Polyisoprenyl Phosphates / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012717:Sesquiterpenes; D013379:Substrate Specificity; D013729:Terpenes; D000094162:Phytoalexins
D004224:Diterpenes; D005875:Gibberellins; D010936:Plant Extracts; D010940:Plant Proteins; D011106:Polyisoprenyl Phosphates; D018749:RNA, Plant; D012717:Sesquiterpenes; D013729:Terpenes; D019883:Alkyl and Aryl Transferases; C105712:ent-kaurene synthetase B; D019755:Carbon-Carbon Lyases; C488968:stemar-13-ene synthase; D007535:Isomerases; C088741:abietadiene cyclase; C002963:geranylgeranyl pyrophosphate; D000094162:Phytoalexins