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Transient decrease of light-harvesting complex II phosphorylation level by hypoosmotic shock in dark-adapted Dunaliella salina.

Xian-De Liu·Fen-Hong Hu·Yun-Gang Shen
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Abstract

This study investigated the regulation of major light harvesting chlorophyll a/b protein (LHCII) phosphorylation by hypoosmotic shock in dark-adapted Dunaliella salina cells. When the external NaCl concentration decreased in darkness, D. salina LHCII phosphorylation levels transiently dropped within 20 min and then restored gradually to basal levels. The transient decrease in LHCII phosphorylation levels was insensitive to NaF, a phosphatase inhibitor. Inhibition of intracellular ATP production by addition of an uncoupler or an ATP synthase inhibitor increased LHCII phosphorylation levels in D. salina cells exposed to hypoosmotic shock. Taken together, these results indicate that hypoosmotic shock inhibits the LHCII phosphorylation process. The related mechanism and physiological significance are discussed.

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Adenosine TriphosphateChlorophytaDarknessEnzyme InhibitorsLightLight-Harvesting Protein ComplexesOsmotic PressurePhosphorylationPhotosystem II Protein ComplexSodium ChlorideSodium FluorideJournal ArticleResearch Support, Non-U.S. Gov't

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Xian-De Liu, Fen-Hong Hu, Yun-Gang Shen. 2006. Transient decrease of light-harvesting complex II phosphorylation level by hypoosmotic shock in dark-adapted Dunaliella salina.. https://doi.org/10.1111/j.1745-7270.2006.00139.x

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