Lewinsohn, E., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States, McKnight Foundation Gijzen, M., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States, Agriculture Canada, London Research Centre, 1400 Western Road, London, Ont. N6G 2V4, Canada Muzika, R.M., U. States Forest. Range Sci. Lab., La Grande, OR 97850, United States, U.S. Dept. of Agric. Forest Service, NE Forest Experimental Station, 180 Canfield St., Morgantown, WV 26505, United States Barton, K., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States, McKnight Foundation Croteau, R., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States
The stem content of diterpene resin acids (rosin) increases dramatically following wounding of grand fir (Abies grandis) saplings, but the level of monoterpene olefins (turpentine) in the stem decreases following injury, in spite of a significant increase in monoterpene cyclase (synthase) activity. However, this observation was explained when rapid evaporative losses of the volatile monoterpenes from the wound site was demonstrated by trapping experiments, a finding consistent with a role of turpentine as a solvent for the mobilization and deposition of rosin to seal the injury. Mature forest trees responded to stem wounding by the enhancement of monoterpene cyclization capacity in a manner similar to 2-year-old grand fir saplings raised in the greenhouse. Light and water stresses greatly reduced the constitutive level of monoterpene cyclase activity and abolished the wound-induced response. The diminution in monoterpene biosynthetic capacity was correlated with a dramatic decrease in cyclase protein as demonstrated by immunoblotting. Relief of stress conditions resulted in the restoration of cyclase activity (both constitutive and wound induced) to control levels. The results of these experiments indicate that grand fir saplings are a suitable model for studies of the regulation of defensive oleoresinosis in conifers.
Oleoresinosis in grand fir (Abies grandis) saplings and mature trees: Modulation of this wound response by light and water stresses
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Lewinsohn, E., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States, McKnight Foundation Gijzen, M., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States, Agriculture Canada, London Research Centre, 1400 Western Road, London, Ont. N6G 2V4, Canada Muzika, R.M., U. States Forest. Range Sci. Lab., La Grande, OR 97850, United States, U.S. Dept. of Agric. Forest Service, NE Forest Experimental Station, 180 Canfield St., Morgantown, WV 26505, United States Barton, K., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States, McKnight Foundation Croteau, R., Institute of Biological Chemistry, Dept. of Biochemistry and Biophysics, Washington State University, Pullman, WA 99164-6340, United States
Oleoresinosis in grand fir (Abies grandis) saplings and mature trees: Modulation of this wound response by light and water stresses
The stem content of diterpene resin acids (rosin) increases dramatically following wounding of grand fir (Abies grandis) saplings, but the level of monoterpene olefins (turpentine) in the stem decreases following injury, in spite of a significant increase in monoterpene cyclase (synthase) activity. However, this observation was explained when rapid evaporative losses of the volatile monoterpenes from the wound site was demonstrated by trapping experiments, a finding consistent with a role of turpentine as a solvent for the mobilization and deposition of rosin to seal the injury. Mature forest trees responded to stem wounding by the enhancement of monoterpene cyclization capacity in a manner similar to 2-year-old grand fir saplings raised in the greenhouse. Light and water stresses greatly reduced the constitutive level of monoterpene cyclase activity and abolished the wound-induced response. The diminution in monoterpene biosynthetic capacity was correlated with a dramatic decrease in cyclase protein as demonstrated by immunoblotting. Relief of stress conditions resulted in the restoration of cyclase activity (both constitutive and wound induced) to control levels. The results of these experiments indicate that grand fir saplings are a suitable model for studies of the regulation of defensive oleoresinosis in conifers.