scholarly journals Monogalactosyldiacylglycerol Deficiency in Arabidopsis Affects Pigment Composition in the Prolamellar Body and Impairs Thylakoid Membrane Energization and Photoprotection in Leaves

2008 ◽  
Vol 148 (1) ◽  
pp. 580-592 ◽  
Author(s):  
Henrik Aronsson ◽  
Mark A. Schöttler ◽  
Amélie A. Kelly ◽  
Christer Sundqvist ◽  
Peter Dörmann ◽  
...  
Keyword(s):  
Thylakoid Membrane ◽  
Prolamellar Body ◽  
Pigment Composition ◽  
Membrane Energization

Curvature thylakoid 1 proteins modulate prolamellar body morphology and promote organized thylakoid biogenesis in Arabidopsis thaliana

2021 ◽  
Vol 118 (42) ◽  
pp. e2113934118
Author(s):  
Omar Sandoval-Ibáñez ◽  
Anurag Sharma ◽  
Michał Bykowski ◽  
Guillem Borràs-Gas ◽  
James B. Y. H. Behrendorff ◽  
...  
Keyword(s):  
Thylakoid Membrane ◽  
Critical Role ◽  
Land Plants ◽  
Prolamellar Body ◽  
Protochlorophyllide Oxidoreductase ◽  
Pigment Composition ◽  
Thylakoid Biogenesis ◽  
Bending Capacity ◽  
Photosynthetic Complexes ◽  
Membrane Bending

The term “de-etiolation” refers to the light-dependent differentiation of etioplasts to chloroplasts in angiosperms. The underlying process involves reorganization of prolamellar bodies (PLBs) and prothylakoids into thylakoids, with concurrent changes in protein, lipid, and pigment composition, which together lead to the assembly of active photosynthetic complexes. Despite the highly conserved structure of PLBs among land plants, the processes that mediate PLB maintenance and their disassembly during de-etiolation are poorly understood. Among chloroplast thylakoid membrane–localized proteins, to date, only Curvature thylakoid 1 (CURT1) proteins were shown to exhibit intrinsic membrane-bending capacity. Here, we show that CURT1 proteins, which play a critical role in grana margin architecture and thylakoid plasticity, also participate in de-etiolation and modulate PLB geometry and density. Lack of CURT1 proteins severely perturbs PLB organization and vesicle fusion, leading to reduced accumulation of the light-dependent enzyme protochlorophyllide oxidoreductase (LPOR) and a delay in the onset of photosynthesis. In contrast, overexpression of CURT1A induces excessive bending of PLB membranes, which upon illumination show retarded disassembly and concomitant overaccumulation of LPOR, though without affecting greening or the establishment of photosynthesis. We conclude that CURT1 proteins contribute to the maintenance of the paracrystalline PLB morphology and are necessary for efficient and organized thylakoid membrane maturation during de-etiolation.

scholarly journals A LARGE SCALE QUASI-CRYSTALLINE LAMELLAR LATTICE IN CHLOROPLASTS OF THE GREEN ALGA ZYGNEMA

1970 ◽  
Vol 45 (3) ◽  
pp. 522-531 ◽  
Author(s):  
Robert J. Mclean ◽  
George F. Pessoney
Keyword(s):  
Internal Structure ◽  
Green Alga ◽  
Thylakoid Membrane ◽  
Large Scale ◽  
Three Dimensional ◽  
Prolamellar Body ◽  
Dimensional Lattice ◽  
Filamentous Green Alga ◽  
Prolamellar Bodies ◽  
Single Membrane

A quasi-crystalline lamellar lattice was observed in chloroplasts of the filamentous green alga Zygnema. The lattice does not appear in the cells until cultures are at the end of the log phase of growth. Pseudograna are also present and become more numerous towards the middle of the log phase. The three-dimensional lattice superficially resembles the configuration of cubic prolamellar bodies but is about 10 times larger and is entirely different in internal structure. The lattice is composed of one or two appressed thylakoids in a stroma matrix which is bounded on each side by a single thylakoid membrane. This multilayered sandwich of membranes and matrix occupies a position equivalent to the single membrane of a cubic prolamellar body.

Herbicides which Interfere with the Biosynthesis of Carotenoids and Their Effect on Pigment Excitation, Chlorophyll Fluorescence and Pigment Composition of the Thylakoid Membrane

1984 ◽  
Vol 39 (5) ◽  
pp. 455-458 ◽  
Author(s):  
K. H. Grumbach
Keyword(s):  
Chlorophyll Fluorescence ◽  
Thylakoid Membrane ◽  
Protein Complexes ◽  
Red Light ◽  
Fluorescence Emission ◽  
Emission Spectra ◽  
Pigment Composition ◽  
Fluorescence Emission Spectra ◽  
Characteristic Emission ◽  
Pigment Protein Complexes

Plants grown in the presence of the herbicides assayed synthesized chlorophylls during growth at low fluence rates. Subsequent irradiation with higher fluence rates of red light induced a strong chlorosis with SAN 6706 being a much stronger herbicide than J 852 or amino-triazole. All herbicides assayed also changed the content and composition of chlorophylls, carotenoids and pigment-protein-complexes of the thylakoid membrane and therefore the pigment excitation and chlorophyll fluorescence emission spectra of the plastid. With increasing herbicide toxicity the main characteristic emission bands at 690 and 730 nm disappeared and new emission bands at 715 (J 852) and 700 nm (SAN 6706) appeared. Such “artificial” membranes with a changed pigment composition were very susceptible to light. Presented data may be taken as evidence, that the lack of photoprotective cyclic carotenoids caused by the specific action of a bleaching herbicide is the primary event that may lead to a disturbed formation of the thylakoid membrane and its destruction by light and oxygen.

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