title: Structure, function and regulation of plant photosystem I.
abstract: Photosystem I (PSI) is a multisubunit protein complex located in the thylakoid membranes of green plants and algae, where it initiates one of the first steps of solar energy conversion by light-driven electron transport. In this review, we discuss recent progress on several topics related to the functioning of the PSI complex, like the protein composition of the complex in the plant Arabidopsis thaliana, the function of these subunits and the mechanism by which nuclear-encoded subunits can be inserted into or transported through the thylakoid membrane. Furthermore, the structure of the native PSI complex in several oxygenic photosynthetic organisms and the role of the chlorophylls and carotenoids in the antenna complexes in light harvesting and photoprotection are reviewed. The special role of the 'red' chlorophylls (chlorophyll molecules that absorb at longer wavelength than the primary electron donor P700) is assessed. The physiology and mechanism of the association of the major light-harvesting complex of photosystem II (LHCII) with PSI during short term adaptation to changes in light quality and quantity is discussed in functional and structural terms. The mechanism of excitation energy transfer between the chlorophylls and the mechanism of primary charge separation is outlined and discussed. Finally, a number of regulatory processes like acclimatory responses and retrograde signalling is reviewed with respect to function of the thylakoid membrane. We finish this review by shortly discussing the perspectives for future research on PSI.
authors: Plant Biochemistry Laboratory, Department of Plant Biology, Faculty of Life Science, University of Copenhagen, DK-1871 Frederiksberg C, Denmark. peje@life.ku.dk
authors: Poul Erik
authors: PE
authors: Jensen
authors: Roberto
authors: R
authors: Bassi
authors: Egbert J
authors: EJ
authors: Boekema
authors: Jan P
authors: JP
authors: Dekker
authors: Stefan
authors: S
authors: Jansson
authors: Dario
authors: D
authors: Leister
authors: Colin
authors: C
authors: Robinson
authors: Henrik Vibe
authors: HV
authors: Scheller
mesh_terms: D017343:Genes, Plant; D008958:Models, Molecular; D010788:Photosynthesis; D045331:Photosystem I Protein Complex / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D045331:Photosystem I Protein Complex