Photoprotection in plants: a new light on photosystem II damage.
Sunlight damages photosynthetic machinery, primarily photosystem II (PSII), and causes photoinhibition that can limit plant photosynthetic activity, growth and productivity. The extent of photoinhibition is associated with a balance between the rate of photodamage and its repair. Recent studies have shown that light absorption by the manganese cluster in the oxygen-evolving complex of PSII causes primary photodamage, whereas excess light absorbed by light-harvesting complexes acts to cause inhibition of the PSII repair process chiefly through the generation of reactive oxygen species. As we review here, PSII photodamage and the inhibition of repair are therefore alleviated by photoprotection mechanisms associated with avoiding light absorption by the manganese cluster and successfully consuming or dissipating the light energy absorbed by photosynthetic pigments, respectively.
Australian Research Council Centre of Excellence in Plant Energy Biology, Research School of Biology, Australian National University, Canberra, ACT 2601, Australia. shunichi.takahashi@anu.edu.au
Shunichi
S
Takahashi
Murray R
MR
Badger
D008345:Manganese / Q000378:metabolism; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000528:radiation effects*; D018515:Plant Leaves / Q000528:radiation effects; D010944:Plants / Q000378:metabolism / Q000528:radiation effects*; D013472:Sunlight
D045332:Photosystem II Protein Complex; D008345:Manganese