title: Light acclimation, retrograde signalling, cell death and immune defences in plants.
abstract: This review confronts the classical view of plant immune defence and light acclimation with recently published data. Earlier findings have linked plant immune defences to nucleotide-binding site leucine-rich repeat (NBS-LRR)-dependent recognition of pathogen effectors and to the role of plasma membrane-localized NADPH-dependent oxidoreductase (AtRbohD), reactive oxygen species (ROS) and salicylic acid (SA). However, recent results suggest that plant immune defence also depends on the absorption of excessive light energy and photorespiration. Rapid changes in light intensity and quality often cause the absorption of energy, which is in excess of that required for photosynthesis. Such excessive light energy is considered to be a factor triggering photoinhibition and disturbance in ROS/hormonal homeostasis, which leads to cell death in foliar tissues. We highlight here the tight crosstalk between ROS- and SA-dependent pathways leading to light acclimation, and defence responses leading to pathogen resistance. We also show that LESION SIMULATING DISEASE 1 (LSD1) regulates and integrates these processes. Moreover, we discuss the role of plastid-nucleus signal transduction, photorespiration, photoelectrochemical signalling and 'light memory' in the regulation of acclimation and immune defence responses. All of these results suggest that plants have evolved a genetic system that simultaneously regulates systemic acquired resistance (SAR), cell death and systemic acquired acclimation (SAA).
authors.affiliation: Department of Plant Genetics, Breeding and Biotechnology, Faculty of Horticulture and Landscape Architecture, Warsaw University of Life Sciences, 02-776 Warszawa, Poland. stanislaw_karpinski@sggw.pl
authors.forename: Stanisław
authors.initials: S
authors.lastname: Karpiński
authors.forename: Magdalena
authors.initials: M
authors.lastname: Szechyńska-Hebda
authors.forename: Weronika
authors.initials: W
authors.lastname: Wituszyńska
authors.forename: Paweł
authors.initials: P
authors.lastname: Burdiak
mesh_terms: D000064:Acclimatization; D016923:Cell Death; D002467:Cell Nucleus / Q000378:metabolism; D019069:Cell Respiration; D006706:Homeostasis; D054884:Host-Pathogen Interactions; D008027:Light; D008954:Models, Biological; D010788:Photosynthesis; D010935:Plant Diseases / Q000276:immunology*; D010937:Plant Growth Regulators / Q000378:metabolism; D057865:Plant Immunity; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D018521:Plant Physiological Phenomena; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D010944:Plants / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000528:radiation effects; D018087:Plastids / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D010937:Plant Growth Regulators; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D020156:Salicylic Acid