@article {4937, title = {High salt-induced PSI-supercomplex is associated with high CEF and attenuation of state transitions}, journal = {Photosynthesis Research}, volume = {157}, year = {2023}, month = {09/2023}, pages = {65 - 84}, abstract = {

While PSI-driven cyclic electron flow (CEF) and assembly of thylakoid supercomplexes have been described in model organisms like Chlamydomonas reinhardtii, open questions remain regarding their contributions to survival under long-term stress. The Antarctic halophyte, C. priscuii UWO241 (UWO241), possesses constitutive high CEF rates and a stable PSI-supercomplex as a consequence of adaptation to permanent low temperatures and high salinity. To understand whether CEF represents a broader acclimation strategy to short- and long-term stress, we compared high salt acclimation between the halotolerant UWO241, the salt-sensitive model, C. reinhardtii, and a moderately halotolerant Antarctic green alga, C. sp. ICE-MDV (ICE-MDV). CEF was activated under high salt and associated with increased non-photochemical quenching in all three Chlamydomonas species. Furthermore, high salt-acclimated cells of either strain formed a PSI-supercomplex, while state transition capacity was attenuated. How the CEF-associated PSI-supercomplex interferes with state transition response is not yet known. We present a model for interaction between PSI-supercomplex formation, state transitions, and the important role of CEF for survival during long-term exposure to high salt.

}, keywords = {LTER-MCM, acclimation, Antarctica, Chlamydomonas, Cyclic electron flow, PSI-supercomplex, salinity, state transitions}, issn = {0166-8595}, doi = {10.1007/s11120-023-01032-y}, url = {https://link.springer.com/10.1007/s11120-023-01032-y}, author = {Kalra, Isha and Wang, Xin and Zhang, Ru and Rachael M. Morgan-Kiss} }