Dlouhý, Ondřej and Karlický, Václav and Arshad, R. and Zsíros, Ottó and Racskóné Domonkos, Ildikó and Wacha, András Ferenc and Bóta, Attila and Garab, Győző (2021) Lipid Polymorphism of the Subchloroplast—Granum and Stroma Thylakoid Membrane–Particles. II. Structure and Functions. CELLS, 10 (9). ISSN 2073-4409
|
Text
cells-10-02363-v3.pdf Available under License Creative Commons Attribution. Download (2MB) | Preview |
Abstract
In Part I, by using P-31-NMR spectroscopy, we have shown that isolated granum and stroma thylakoid membranes (TMs), in addition to the bilayer, display two isotropic phases and an inverted hexagonal (H-II) phase; saturation transfer experiments and selective effects of lipase and thermal treatments have shown that these phases arise from distinct, yet interconnectable structural entities. To obtain information on the functional roles and origin of the different lipid phases, here we performed spectroscopic measurements and inspected the ultrastructure of these TM fragments. Circular dichroism, 77 K fluorescence emission spectroscopy, and variable chlorophyll-a fluorescence measurements revealed only minor lipase- or thermally induced changes in the photosynthetic machinery. Electrochromic absorbance transients showed that the TM fragments were re-sealed, and the vesicles largely retained their impermeabilities after lipase treatments-in line with the low susceptibility of the bilayer against the same treatment, as reflected by our P-31-NMR spectroscopy. Signatures of H-II-phase could not be discerned with small-angle X-ray scattering-but traces of H-II structures, without long-range order, were found by freeze-fracture electron microscopy (FF-EM) and cryo-electron tomography (CET). EM and CET images also revealed the presence of small vesicles and fusion of membrane particles, which might account for one of the isotropic phases. Interaction of VDE (violaxanthin de-epoxidase, detected by Western blot technique in both membrane fragments) with TM lipids might account for the other isotropic phase. In general, non-bilayer lipids are proposed to play role in the self-assembly of the highly organized yet dynamic TM network in chloroplasts.
| Item Type: | Article |
|---|---|
| Additional Information: | Funding Agency and Grant Number: Czech Science FoundationGrant Agency of the Czech Republic [GACR 19-13637S]; National Research Development and Innovation Office of HungaryNational Research, Development & Innovation Office (NRDIO) - Hungary [OTKA K 128679]; Hungarian Ministry for National Economy [GINOP-2.3.2-152016-00058]; project "SustES-Adaptation strategies for sustainable ecosystem services and food security under adverse environmental conditions" [CZ.02.1.01/0.0/0.0/16_019/0000797]; Ministry of Education, Youth and Sports of CR within the CzeCOS program [LM2018123]; European Regional Development Fund (ERDF) project 'Plants as a tool for sustainable global development' [CZ.02.1.01/0.0/0.0/16_019/0000827]; Silesian Region [07359/2019/RRC]; University of Ostrava [SGS02/P.rF/2021]; MEYS CR [LM2015043]; CF Cryo-electron Microscopy and Tomography Funding text: This work was supported by grants from the Czech Science Foundation (GAC. R 19-13637S to G.G., V.S., V.K., I.K. and O.D.), the National Research Development and Innovation Office of Hungary (OTKA K 128679 to G.G.), the Hungarian Ministry for National Economy (GINOP-2.3.2-152016-00058 to I.D.), the project "SustES-Adaptation strategies for sustainable ecosystem services and food security under adverse environmental conditions" (CZ.02.1.01/0.0/0.0/16_019/0000797, to V.S. and V.K.), by the Ministry of Education, Youth and Sports of CR within the CzeCOS program (no. LM2018123 to I.K. and V.K.), by the European Regional Development Fund (ERDF) project `Plants as a tool for sustainable global development' (no. CZ.02.1.01/0.0/0.0/16_019/0000827), the Silesian Region (07359/2019/RRC to O.D.) and the University of Ostrava (SGS02/P.rF/2021 to O.D.). The 31P-NMR measurements were performed in the NMR Center of CERIC-ERIC. We thank CIISB research infrastructure project LM2015043, funded by MEYS CR; financial support of the measurements at the CF Cryo-electron Microscopy and Tomography is gratefully acknowledged. |
| Subjects: | Q Science / természettudomány > QH Natural history / természetrajz > QH301 Biology / biológia > QH3011 Biochemistry / biokémia R Medicine / orvostudomány > RC Internal medicine / belgyógyászat |
| SWORD Depositor: | MTMT SWORD |
| Depositing User: | MTMT SWORD |
| Date Deposited: | 03 Feb 2022 12:53 |
| Last Modified: | 03 Feb 2022 12:53 |
| URI: | http://real.mtak.hu/id/eprint/137219 |
Actions (login required)
 |
Edit Item |
