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Temperature/light dependent development of selective resistance to photoinhibition of photosystem I.
- Source :
-
FEBS letters [FEBS Lett] 1998 Jul 03; Vol. 430 (3), pp. 288-92. - Publication Year :
- 1998
-
Abstract
- Exposure of winter rye leaves grown at 20 degrees C and an irradiance of either 50 or 250 micromol m(-2) s(-1) to high light stress (1600 micromol m(-2) s(-1), 4 h) at 5 degrees C resulted in photoinhibition of PSI measured in vivo as a 34% and 31% decrease in deltaA820/A820 (P700+). The same effect was registered in plants grown at 5 degrees C and 50 micromol m(-2) s(-1). This was accompanied by a parallel degradation of the PsaA/PsaB heterodimer, increase of the intersystem e- pool size as well as inhibition of PSII photochemistry measured as Fv/Fm. Surprisingly, plants acclimated to high light (800 micromol m(-2) s(-1)) or to 5 degrees C and moderate light (250 micromol m(-2) s(-1)) were fully resistant to photoinhibition of PSI and did not exhibit any measurable changes at the level of PSI heterodimer abundance and intersystem e- pool size, although PSII photochemistry was reduced to 66% and 64% respectively. Thus, we show for the first time that PSI, unlike PSII, becomes completely resistant to photoinhibition when plants are acclimated to either 20 degrees C/800 micromol m(-2) s(-1) or 5 degrees C/250 micromol m(-2) s(-1) as a response to growth at elevated excitation pressure. The role of temperature/light dependent acclimation in the induction of selective tolerance to PSI photoinactivation is discussed.
- Subjects :
- Chloroplasts
Electron Spin Resonance Spectroscopy
Intracellular Membranes
Membrane Proteins analysis
Oxidation-Reduction
Plant Leaves
Radiation Tolerance
Secale radiation effects
Spectrophotometry, Infrared
Temperature
Light
Photosynthetic Reaction Center Complex Proteins radiation effects
Photosystem I Protein Complex
Secale growth & development
Subjects
Details
- Language :
- English
- ISSN :
- 0014-5793
- Volume :
- 430
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- FEBS letters
- Publication Type :
- Academic Journal
- Accession number :
- 9688557
- Full Text :
- https://doi.org/10.1016/s0014-5793(98)00681-4