Title: | A wound- and systemin-inducible polygalacturonase in tomato leaves |
Author(s): | Bergey DR; Orozco-Cardenas M; de Moura DS; Ryan CA; |
Address: | "Institute of Biological Chemistry, Washington State University, Pullman, WA 99164-6340, USA" |
ISSN/ISBN: | 0027-8424 (Print) 1091-6490 (Electronic) 0027-8424 (Linking) |
Abstract: | "Oligogalacturonide fragments that activate defensive genes in plant leaves heretofore have been thought to be generated only by pathogen-derived pectin-degrading enzymes, because polygalacturonase (PG) activity has not been reported in leaves. Here, we report that mRNAs encoding a PG catalytic subunit protein and its regulatory (beta-subunit) protein are expressed in tomato leaves in response to wounding, systemin, and oligosaccharide elicitors. Synthesis of the two subunits in response to wounding is systemic and is accompanied by an increase in PG activity in extracts from both wounded and unwounded leaves. The finding that PG subunit mRNAs and PG enzyme activity are induced by wounding indicates that herbivore attacks can produce endogenous oligogalacturonide elicitors that may be involved in the local and systemic activation of defense responses against both herbivores and pathogens" |
Keywords: | "Amino Acid Sequence Enzyme Induction Gene Expression Regulation, Plant Kinetics Solanum lycopersicum/*enzymology/genetics Macromolecular Substances Molecular Sequence Data Peptides/pharmacology/*physiology Plant Leaves/enzymology Plant Proteins/physiology;" |
Notes: | "MedlineBergey, D R Orozco-Cardenas, M de Moura, D S Ryan, C A eng Comparative Study Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. 1999/02/17 Proc Natl Acad Sci U S A. 1999 Feb 16; 96(4):1756-60. doi: 10.1073/pnas.96.4.1756" |