title: Emerging trade-offs - impact of photoprotectants (PsbS,  xanthophylls, and vitamin E) on oxylipins as regulators of  development and defense.
abstract: This review summarizes evidence for a mechanistic link between plant photoprotection and the synthesis of oxylipin hormones as regulators of development and defense. Knockout mutants of Arabidopsis, deficient in various key components of the chloroplast photoprotection system, consistently produced greater concentrations of the hormone jasmonic acid or its precursor 12- oxo-phytodienoic acid (OPDA), both members of the oxylipin messenger family. Characterized plants include several mutants deficient in PsbS (an intrinsic chlorophyll-binding protein of photosystem II) or pigments (zeaxanthin and/or lutein) required for photoprotective thermal dissipation of excess excitation energy in the chloroplast and a mutant deficient in reactive oxygen detoxification via the antioxidant vitamin E (tocopherol). Evidence is also presented that certain plant defenses against herbivores or pathogens are elevated for these mutants. This evidence furthermore indicates that wild-type Arabidopsis plants possess less than maximal defenses against herbivores or pathogens, and suggest that plant lines with superior defenses against abiotic stress may have lower biotic defenses. The implications of this apparent trade-off between abiotic and biotic plant defenses for plant ecology as well as for plant breeding/engineering are explored, and the need for research further addressing this important issue is highlighted.
authors: Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309-0334, USA. barabara.demmigadams@colorado.edu
authors: Barbara
authors: B
authors: Demmig-Adams
authors: Christopher M
authors: CM
authors: Cohu
authors: Véronique
authors: V
authors: Amiard
authors: Guusvan
authors: G
authors: Zadelhoff
authors: Gerrit A
authors: GA
authors: Veldink
authors: Onno
authors: O
authors: Muller
authors: William W
authors: WW
authors: Adams
mesh_terms: D017360:Arabidopsis / Q000378:metabolism / Q000502:physiology* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002736:Chloroplasts / Q000378:metabolism / Q000502:physiology; D045342:Light-Harvesting Protein Complexes / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D054883:Oxylipins / Q000378:metabolism*; D045332:Photosystem II Protein Complex / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013472:Sunlight; D014810:Vitamin E / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D024341:Xanthophylls / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D045342:Light-Harvesting Protein Complexes; C489731:NPQ4 protein, Arabidopsis; D054883:Oxylipins; D045332:Photosystem II Protein Complex; D010937:Plant Growth Regulators; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D024341:Xanthophylls; D014810:Vitamin E