Characterization of the preferred cation cofactors of chloroplast protein kinases in Arabidopsis thaliana. Issue 3 (31st January 2023)

• Record Type: Journal Article
• Authors: Espinoza‐Corral, Roberto; Schwenkert, Serena; Schneider, Anja
• Is Part Of: FEBS open bio. Volume 13:Issue 3(2023)
• Page Start: 511
• Page End: 518
• Publication Date: 2023-01-31
• Subjects: Arabidopsis -- cation homeostasis -- chloroplast -- protein phosphorylation; Molecular biology -- Periodicals; Cytology -- Periodicals; Life sciences -- Periodicals; Biological Science Disciplines -- Periodicals; Molecular Biology -- Periodicals; Cell Biology -- Periodicals; Cytology; Life sciences; Molecular biology; Periodicals; 572.805
• DOI: 10.1002/2211-5463.13563
• Languages: English
• ISSNs: 2211-5463

Abstract

Abstract : Chloroplasts sense a variety of stimuli triggering several acclimation responses. One prominent response is the mechanism of state transitions, which enables rapid adaption to changes in illumination. Here, we investigated the link between divalent cations (calcium, magnesium, and manganese) and protein kinase activity in Arabidopsis chloroplasts. Our results show that manganese ions are the strongest activator of kinase activity in chloroplasts followed by magnesium ions, whereas calcium ions are not able to induce kinase activity. Additionally, the phosphorylation of specific protein bands is strongly reduced in chloroplasts of a cmt1 mutant, which is impaired in manganese import into chloroplasts, as compared to the wild‐type. These findings provide insights for the future characterization of chloroplast protein kinase activity and potential target proteins. Abstract : Plant chloroplasts contain protein kinases that regulate vital processes such as photosynthesis. Despite their similarity with other kinases of eukaryotic origin, chloroplast kinases have shown features that suggest their divergence from the eukaryotic branch, such as their preference for cation cofactors. Using chloroplasts from the model plant Arabidopsis thaliana, we demonstrate that chloroplast kinases prefer manganese and magnesium over calcium.