Architectural switch in plant photosynthetic membranes induced by light stress
2012 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, no 49, 20130-20135 p.Article in journal (Refereed) Published
Unavoidable side reactions of photosynthetic energy conversion can damage the water-splitting photosystem II (PSII) holocomplex embedded in the thylakoid membrane system inside chloroplasts. Plant survival is crucially dependent on an efficient molecular repair of damaged PSII realized by a multistep repair cycle. The PSII repair cycle requires a brisk lateral protein traffic between stacked grana thylakoids and unstacked stroma lamellae that is challenged by the tight stacking and low protein mobility in grana. We demonstrated that high light stress induced two main structural changes that work synergistically to improve the accessibility between damaged PSII in grana and its repair machinery in stroma lamellae: lateral shrinkage of grana diameter and increased protein mobility in grana thylakoids. It follows that high light stress triggers an architectural switch of the thylakoid network that is advantageous for swift protein repair. Studies of the thylakoid kinase mutant stn8 and the double mutant stn7/8 demonstrate the central role of protein phosphorylation for the structural alterations. These findings are based on the elaboration of mathematical tools for analyzing confocal laser-scanning microscopic images to study changes in the sophisticated thylakoid architecture in intact protoplasts.
Place, publisher, year, edition, pages
National Academy of Sciences; 1999 , 2012. Vol. 109, no 49, 20130-20135 p.
confocal microscopy, macromolecular crowding, photosynthesis
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-86891DOI: 10.1073/pnas.1214265109ISI: 000312347200057OAI: oai:DiVA.org:liu-86891DiVA: diva2:583047
Funding Agencies|Washington State Agricultural Research Center||National Science Foundation|MCB-1158571|United States-Israel Binational Agricultural Research and Development Fund|US-4334-10|2013-01-072013-01-072013-01-07