Trichome glands on the surface of many higher plants produce and secrete exudates affecting insects, microbes, and herbivores. Metabolic engineering of gland exudation has potential for improving pest/disease resistance, and for facilitating molecular farming. We identified a cytochrome P450 hydroxylase gene specific to the trichome gland and used both antisense and sense co-suppression strategies to investigate its function. P450-suppressed transgenic tobacco plants showed a ≥41% decrease in the predominant exudate component, cembratriene-diol (CBT-diol), and a ≥19-fold increase in its precursor, cembratriene-ol (CBT-ol). Thus, the level of CBT-ol was raised from 0.2 to ≥4.3% of leaf dry weight. Exudate from antisense-expressing plants had higher aphidicidal activity, and transgenic plants with exudate containing high concentrations of CBT-ol showed greatly diminished aphid colonization responses. Our results demonstrate the feasibility of significantly modifying the natural-product chemical composition and aphid-interactive properties of gland exudates using metabolic engineering. The results also have implications for molecular farming.
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Dell, B. & McComb, J.A. Plant resins–their formation, secretion, and possible functions. Adv. Bot. Res. 6, 276–316 (1978).
Wagner, G.J. Secreting glandular trichomes: more than just hairs. Plant Physiol. 96, 675–679 (1991).
Duke, S.O. et al. Sequestration of phytotoxins by plants: implications for biosynthetic production. In Biologically active natural products: agrochemicals. (eds Cutler, H.G. & Cutler, S.J.) 127–136 (CRC Press, Boca Raton, FL; 1999).
Phillips, M.A. & Croteau, R.B. Resin-based defenses in conifers. Trends Plant Sci. 4, 184–190 (1999).
Kelsey, R.G., Reynolds, G.W. & Rodriguez, E. The chemistry of biologically active constituents secreted and stored in plant glandular trichomes. In Biology and chemistry of plant trichomes. (eds Rodriguez, E., Healey, P.L. & Mehta, I.) 187–241 (Plenum Press, New York; 1984).
Lin, Y. & Wagner, G.J. Surface disposition and stability of pest-interactive, trichome-exudated diterpenes and sucrose esters of tobacco. J. Chem. Ecol. 20, 1907–1921 (1994).
Wagner, G.J. Tobacco surface chemistry. In Tobacco production, chemistry and technology. (eds Davis, D.L. & Nielsen, M.T.) 292–303 (Blackwell Science, Malden, MA; 1999).
Olsson, E., Holth, A., Kumlin, E., Bohlin, L. & Wahlberg, I. Structure-related inhibiting activity of some tobacco cembranoids on the prostaglandin synthesis in vitro. Planta Med. 59, 293–295 (1993).
Wahlberg, I. & Eklund, A.M. Cembranoids, pseudopteranoids, and cubitanoids of natural occurrence. Prog. Chem. Org. Natural Prod. 59, 141–276 (1992).
Tius, M.A. Synthesis of cembranes and cembranolides. Chem. Rev. 88, 719–1191 (1988).
Guo, Z. & Wagner, G.J. Biosynthesis of cembratrienols in cell-free extracts from trichomes of Nicotiana tabacum. Plant Sci. 110, 1–10 (1995).
Chapple, C. Molecular-genetic analysis of plant cytochrome P450-dependent monooxygenases. Annu. Rev. Plant Physiol. Plant Mol. Biol. 49, 311–343 (1998).
Nelson, D. Cytochrome P450 Homepage. http://drnelson.utmem.edu/CytochromeP450.html
Hutvágner, G., Barta, E. & Bánfalvi, Z. Isolation and sequence analysis of a cDNA and a related gene for cytochrome P450 proteins from Solanum chacoense. Gene 188, 247–252 (1997).
Schardl, C.L. et al. Design and construction of a versatile system for the expression of foreign genes in plants. Gene 61, 1–11 (1987).
Guo Z. &. Wagner, G.J. Biosynthesis of cis-abienol in cell-free extracts of tobacco trichomes. Arch. Biochem. Biophys. 308, 103–108 (1993).
Kroumova, A., Xie, Z. & Wagner, G.J. A pathway for synthesis of straight and branched, odd and even length, medium chain fatty acids in plants. Proc. Natl. Acad. Sci. USA 91, 11437–11441 (1994).
Kroumova, A.B., Kandra,L. & Wagner, G.J. Comparison of mechanisms for elongation to form branched-chain, alkyl components of sugar esters, epi-cuticular wax esters and volatilized 4-methyl-1-hexanol. Adv. Plant Lipid Res. 13, 91–94 (1998).
Jackson, D.M. & Danehower, D.A. Integrated case study: Nicotiana leaf surface components and their effects on insect pests and disease. In Plant cuticles: an integrated functional approach. (ed. Kerstiens, G.) 231–254 (BIOS Scientific Publishers, Oxford, UK; 1996).
Severson, R.F., Eckel, R.V.W., Jackson, D.M., Sisson, V.A. & Stephenson, M.G. Aphicidal activity of cuticular components from Nicotiana tabacum. In Natural and engineered pest management agents, ACS Symposium Series No. 551. (eds Hedin, P.A., Menn, J.J. & Hollingworth, R.M.) 172–179 (American Chemical Society, Washington, DC; 1994).
Robertson, J.L. & Preisler, H.K. Pesticide bioassays with arthropods. (CRC Press, Boca Raton, FL; 1992).
Severson, R.F. et al. Isolation and characterization of sucrose esters of the cuticular waxes of green tobacco leaf. J. Agric. Food Chem. 33, 870–875 (1985).
Horsch, R.B., et al. Leaf disc transformation. In Plant molecular biology manual. (eds Gelvin, S.B. & Schilperoort, R.A.) A5:1–9 (Kluwer Academic Publishers, Dordrecht, The Netherlands; 1988).
Sambrook, J., Fritsch, E.F. & Maniatis, T. Molecular cloning, Edn. 2. (Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY; 1989).
Silverstein, R.M. & Webster, F.X. Spectrometric identification of organic compounds, Edn. 6. (Wiley, New York; 1998).
Special thanks go to D.M. Jackson for advice on aphid manipulations, P.L. Cornelius for assistance with statistical analysis, and G.M. Cheniae and K.F. Haynes for comments. We thank Charles Jones, Ryan Shepherd, and Lynn Zaleweski for assistance. The work was supported by grants from the Department of Energy Basic Energy Sciences (G.J.W.), Tobacco and Health Research Institute, University of Kentucky (Lexington, KY; G.J.W. and S.G.), and National Science Foundation/US Department of Agriculture–National Research Initiative, Interagency Metabolic Engineering 90.0 (G.J.W.).
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Quantitative analysis of cembranoids in tobacco leaf by using heart‐cutting two‐dimensional liquid chromatography
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