Plant responses to UV radiation and links to pathogen resistance.
Increased incident ultraviolet (UV) radiation due to ozone depletion has heightened interest in plant responses to UV because solar UV wavelengths can reduce plant genome stability, growth, and productivity. These detrimental effects result from damage to cell components including nucleic acids, proteins, and membrane lipids. As obligate phototrophs, plants must counter the onslaught of cellular damage due to prolonged exposure to sunlight. They do so by attenuating the UV dose received through accumulation of UV-absorbing secondary metabolites, neutralizing reactive oxygen species produced by UV, monomerizing UV-induced pyrimidine dimers by photoreactivation, extracting UV photoproducts from DNA via nucleotide excision repair, and perhaps transiently tolerating the presence of DNA lesions via replicative bypass of the damage. The signaling mechanisms controlling these responses suggest that UV exposure also may be beneficial to plants by increasing cellular immunity to pathogens. Indeed, pathogen resistance can be enhanced by UV treatment, and recent experiments suggest DNA damage and its processing may have a role.
Kunz
Bernard A
BA
School of Life and Environmental Sciences, Deakin University, Geelong, Victoria 3217, Australia.
Cahill
David M
DM
Mohr
Peter G
PG
Osmond
Megan J
MJ
Vonarx
Edward J
EJ
D004249:DNA Damage; D004260:DNA Repair; D018744:DNA, Plant / Q000378:metabolism / Q000528:radiation effects; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000378:metabolism; D005609:Free Radicals / Q000378:metabolism; D005658:Fungi / Q000472:pathogenicity* / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects*; D007113:Immunity, Innate; D015227:Lipid Peroxidation; D008563:Membrane Lipids / Q000378:metabolism / Q000528:radiation effects; D018384:Oxidative Stress / Q000528:radiation effects*; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000821:virology; D010940:Plant Proteins / Q000378:metabolism / Q000528:radiation effects; D010942:Plant Viruses / Q000472:pathogenicity* / Q000528:radiation effects; D010944:Plants / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000528:radiation effects*; D011836:Radiation Tolerance; D014466:Ultraviolet Rays
D018744:DNA, Plant; D005609:Free Radicals; D008563:Membrane Lipids; D010940:Plant Proteins; D004255:Deoxyribodipyrimidine Photo-Lyase