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Title: High salt-induced PSI-supercomplex is associated with high CEF and attenuation of state transitions
Abstract While PSI-driven cyclic electron flow (CEF) and assembly of thylakoid supercomplexes have been described in model organisms likeChlamydomonas reinhardtii, open questions remain regarding their contributions to survival under long-term stress. The Antarctic halophyte,C. priscuiiUWO241 (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 threeChlamydomonasspecies. 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.  more » « less
Award ID(s):
2224760
PAR ID:
10537615
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Photosynthesis Research
Volume:
157
Issue:
2-3
ISSN:
0166-8595
Page Range / eLocation ID:
65 to 84
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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