| Title: | Polyphenol oxidase from hybrid poplar. Cloning and expression in response to wounding and herbivory |
| Author(s): | Constabel CP; Yip L; Patton JJ; Christopher ME; |
| Address: | "Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada TGG 2E9. peter.constabel@ualberta.ca" |
| ISSN/ISBN: | 0032-0889 (Print) 1532-2548 (Electronic) 0032-0889 (Linking) |
| Abstract: | "The inducible expression of polyphenol oxidase (PPO), a presumed antiherbivore enzyme, was examined in hybrid poplar (Populus trichocarpa x Populus deltoides). Following mechanical wounding simulating insect damage, PPO activity increased dramatically in wounded and unwounded leaves on wounded plants beginning at 24 and 48 h, respectively. A hybrid poplar PPO cDNA was isolated and its nucleotide sequence determined. On northern blots, PPO transcripts were detected within 8 h of wounding, and reached peak levels at 16 and 24 h in wounded and unwounded leaves, respectively. Methyl jasmonate spray and feeding by forest tent caterpillar also induced PPO expression. The induction of PPO was strongest in the youngest four leaves, which were generally avoided by caterpillars in free feeding experiments. This wound- and herbivore-induced expression of PPO in hybrid poplar supports the defensive role of this protein against insect pests" |
| Keywords: | "Acetates/pharmacology Amino Acid Sequence Animals Base Sequence Blotting, Northern Blotting, Southern Catechol Oxidase/biosynthesis/*genetics Cloning, Molecular Crosses, Genetic Cyclopentanes/pharmacology DNA, Complementary/analysis Enzyme Induction *Gene;" |
| Notes: | "MedlineConstabel, C P Yip, L Patton, J J Christopher, M E eng Research Support, Non-U.S. Gov't 2000/09/12 Plant Physiol. 2000 Sep; 124(1):285-95. doi: 10.1104/pp.124.1.285" |
