Research article2006Peer reviewedOpen access
Digalactosyl-diacylglycerol deficiency impairs the capacity for photosynthetic intersystem electron transport and state transitions in Arabidopsis thaliana due to photosystem I acceptor-side limitations
Ivanov, Alexander G.; Hendrickson, Luke; Krol, Marianna; Selstam, Eva; Öquist, Gunnar; Hurry, Vaughan ; Huner, Norman P. A.
Abstract
Compared with wild type, the dgd1 mutant of Arabidopsis thaliana exhibited a lower amount of PSI-related Chl-protein complexes and lower abundance of the PSI-associated polypeptides, PsaA, PsaB, PsaC, PsaL and PsaH, with no changes in the levels of Lhcal-4. Functionally, the dgd1 mutant exhibited a significantly lower light-dependent, steady-state oxidation level of P700 (P700(+)) in vivo, a higher intersystem electron pool size, restricted linear electron transport and a higher rate of reduction of P700(+) in the dark, indicating an increased capacity for PSI cyclic electron transfer compared with the wild type. Concomitantly, the dgd1 mutant exhibited a higher sensitivity to and incomplete recovery of photoinhibition of PSI. Furthermore, dgd1 exhibited a lower capacity to undergo state transitions compared with the wild type, which was associated with a higher reduction state of the plastoquinone (PQ) pool. We conclude that digalactosyl-diacylglycerol (DGDG) deficiency results in PSI acceptor-side limitations that alter the flux of electrons through the photosynthetic electron chain and impair the regulation of distribution of excitation energy between the photosystems. These results are discussed in terms of thylakoid membrane domain reorganization in response to DGDG deficiency in A. thaliana.
Keywords
Arabidopsis dgd1 mutant; chlorophyll fluorescence; digalactosyl-diacylglycerol; photoinhibition; P700; state transitions
Published in
Plant and Cell Physiology
2006, Volume: 47, number: 8, pages: 1146-1157
Publisher: OXFORD UNIV PRESS
UKÄ Subject classification
Botany
Publication identifier
DOI: https://doi.org/10.1093/pcp/pcj089
Permanent link to this page (URI)
https://res.slu.se/id/publ/76351