Changes in the Composition of the Photosynthetic Apparatus in the Galactolipid-Deficient dgd1 Mutant of Arabidopsis thaliana
Open Access
- 1 November 1997
- journal article
- Published by Oxford University Press (OUP) in Plant Physiology
- Vol. 115 (3), 1175-1184
- https://doi.org/10.1104/pp.115.3.1175
Abstract
The glycerolipid digalactosyl diacylglycerol (DGDG) is exclusively associated with photosynthetic membranes and thus may play a role in the proper assembly and maintenance of the photosynthetic apparatus. Here we employ a genetic approach based on the dgd1 mutant of Arabidopsis thaliana to investigate the function of DGDG in thylakoid membranes. The primary defect in the genetically well-characterized dgd1 mutant resulted in a 90% reduction of the DGDG content. The mutant showed a decreased photosystem II (PSII) to photosystem I ratio. In vivo room- and low-temperature (77 K) chlorophyll fluorescence measurements with thylakoid preparations are in agreement with a drastically altered excitation energy allocation to the reaction centers. Quantification of pigment-binding apoproteins and pigments supports an altered stoichiometry of individual pigment-protein complexes in the mutant. Most strikingly, an increase in the amount of peripheral light-harvesting complexes of PSII relative to the inner antenna complexes and the PSII reaction center/core complexes was observed. Regardless of the severe alterations in thylakoid organization, photosynthetic oxygen evolution was virtually not compromised in dgd1 mutant leaves.Keywords
This publication has 24 references indexed in Scilit:
- Chlorophyll a/b-Binding Proteins, Pigment Conversions, and Early Light-Induced Proteins in a Chlorophyll b-less Barley MutantPlant Physiology, 1995
- Analysis of the Pigment Stoichiometry of Pigment-Protein Complexes from Barley (Hordeum vulgare) (The Xanthophyll Cycle Intermediates Occur Mainly in the Light-Harvesting Complexes of Photosystem I and Photosystem II)Plant Physiology, 1995
- Atomic model of plant light-harvesting complex by electron crystallographyNature, 1994
- The Effects of Illumination on the Xanthophyll Composition of the Photosystem II Light-Harvesting Complexes of Spinach Thylakoid MembranesPlant Physiology, 1994
- Lipid-protein Interactions in Crystals of Plant Light-harvesting ComplexJournal of Molecular Biology, 1993
- Biochemistry and Function of the Plastid EnvelopeAnnual Review of Cell Biology, 1990
- Genetically engineered mutant of the cyanobacterium Synechocystis 6803 lacks the photosystem II chlorophyll-binding protein CP-47Proceedings of the National Academy of Sciences of the United States of America, 1986
- Analysis of Photosynthetic Antenna Function in a Mutant of Arabidopsis thaliana (L.) Lacking trans-Hexadecenoic AcidPlant Physiology, 1985
- Differentiation of chloroplast lamellaeArchives of Biochemistry and Biophysics, 1976
- New evidence supporting energy transfer between photosynthetic unitsBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1973