The nonmevalonate pathway supports both monoterpene and sesquiterpene formation in snapdragon flowers
AUTOR(ES)
Dudareva, Natalia
FONTE
National Academy of Sciences
RESUMO
Terpenoids, the largest class of plant secondary metabolites, play essential roles in both plant and human life. In higher plants, the five-carbon building blocks of all terpenoids, isopentenyl diphosphate (IPP) and dimethylallyl diphosphate, are derived from two independent pathways localized in different cellular compartments. The methylerythritol phosphate (MEP or nonmevalonate) pathway, localized in the plastids, is thought to provide IPP and dimethylallyl diphosphate for hemiterpene, monoterpene, and diterpene biosynthesis, whereas the cytosol-localized mevalonate pathway provides C5 units for sesquiterpene biosynthesis. Stable isotope-labeled, pathway-specific precursors (1-deoxy-[5,5-2H2]-d-xylulose and [2,2-2H2]-mevalolactone) were supplied to cut snapdragon flowers, which emit both monoterpenes and the sesquiterpene, nerolidol. We show that only one of the two pathways, the plastid-localized MEP pathway, is active in the formation of volatile terpenes. The MEP pathway provides IPP precursors for both plastidial monoterpene and cytosolic sesquiterpene biosynthesis in the epidermis of snapdragon petals. The trafficking of IPP occurs unidirectionally from the plastids to cytosol. The MEP pathway operates in a rhythmic manner controlled by the circadian clock, which determines the rhythmicity of terpenoid emission.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=545543Documentos Relacionados
- Developmental Regulation of Methyl Benzoate Biosynthesis and Emission in Snapdragon Flowers
- Regulation of Methylbenzoate Emission after Pollination in Snapdragon and Petunia Flowers
- Evidence of a Role for LytB in the Nonmevalonate Pathway of Isoprenoid Biosynthesis
- The Arabidopsis IspH Homolog Is Involved in the Plastid Nonmevalonate Pathway of Isoprenoid Biosynthesis
- A 1-deoxy-d-xylulose 5-phosphate reductoisomerase catalyzing the formation of 2-C-methyl-d-erythritol 4-phosphate in an alternative nonmevalonate pathway for terpenoid biosynthesis