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AtFKBP16-1, a chloroplast lumenal immunophilin, mediates response to photosynthetic stress by regulating PsaL stability.

ABSTRACT: Arabidopsis contains 16 putative chloroplast lumen-targeted immunophilins (IMMs). Proteomic analysis has enabled the subcellular localization of IMMs experimentally, but the exact biological and physiological roles of most luminal IMMs remain to be discovered. FK506-binding protein (FKBP) 16-1, one of the lumenal IMMs containing poorly conserved amino acid residues for peptidyl-prolyl isomerase (PPIase) activity, was shown to play a possible role in chloroplast biogenesis in Arabidopsis, and was also found to interact with PsaL in wheat. In this study, further evidence is provided for the notion that Arabidopsis FKBP16-1 (AtFKBP16-1) is transcriptionally and post-transcriptionally regulated by environmental stresses including high light (HL) intensity, and that overexpression of AtFKBP16-1 plants exhibited increased photosynthetic stress tolerance. A blue native-polyacrylamide gel electrophoresis/two-dimensional (BN-PAGE/2-D) analysis revealed that the increase of AtFKBP16-1 affected the levels of photosystem I (PSI)-light harvesting complex I (LHCI) and PSI-LHCI-light harvesting complex II (LHCII) supercomplex, and consequently enhanced tolerance under conditions of HL stress. In addition, plants overexpressing AtFKBP16-1 showed increased accumulation of PsaL protein and enhanced drought tolerance. Using a protease protection assay, AtFKBP16-1 protein was found to have a role in PsaL stability. The AtPsaL levels also responded to abiotic stresses derived from drought, and from methyl viologen stresses in wild-type plants. Taken together, these results suggest that AtFKBP16-1 plays a role in the acclimation of plants under photosynthetic stress conditions, probably by regulating PsaL stability.

SUBMITTER: Seok MS

PROVIDER: S-EPMC4282393 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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AtFKBP16-1, a chloroplast lumenal immunophilin, mediates response to photosynthetic stress by regulating PsaL stability.

Seok Min Sook MS You Young Nim YN Park Hyun Ji HJ Lee Sang Sook SS Aigen Fu F Luan Sheng S Ahn Jun Cheul JC Cho Hye Sun HS

Physiologia plantarum 20131030 4

Arabidopsis contains 16 putative chloroplast lumen-targeted immunophilins (IMMs). Proteomic analysis has enabled the subcellular localization of IMMs experimentally, but the exact biological and physiological roles of most luminal IMMs remain to be discovered. FK506-binding protein (FKBP) 16-1, one of the lumenal IMMs containing poorly conserved amino acid residues for peptidyl-prolyl isomerase (PPIase) activity, was shown to play a possible role in chloroplast biogenesis in Arabidopsis, and was ...[more]

PMID: 24124981

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Dataset Information

AtFKBP16-1, a chloroplast lumenal immunophilin, mediates response to photosynthetic stress by regulating PsaL stability.

Publications

AtFKBP16-1, a chloroplast lumenal immunophilin, mediates response to photosynthetic stress by regulating PsaL stability.

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