Premium
Light regulation of CaS, a novel phosphoprotein in the thylakoid membrane of Arabidopsis thaliana
Author(s) -
Vain Julia P.,
Sakuragi Yumiko,
Stael Simon,
Tikkanen Mikko,
Allahverdiyeva Yagut,
Paakkarinen Virpi,
Aro Eveliina,
Suorsa Marjaana,
Scheller Henrik V.,
Vener Alexander V.,
Aro EvaMari
Publication year - 2008
Publication title -
the febs journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.981
H-Index - 204
eISSN - 1742-4658
pISSN - 1742-464X
DOI - 10.1111/j.1742-4658.2008.06335.x
Subject(s) - thylakoid , phosphorylation , arabidopsis , biology , arabidopsis thaliana , phosphoprotein , chloroplast , microbiology and biotechnology , protein phosphorylation , stroma , kinase , twin arginine translocation pathway , biochemistry , protein kinase a , gene , immunology , immunohistochemistry , mutant
Exposure of Arabidopsis thaliana plants to high levels of light revealed specific phosphorylation of a 40 kDa protein in photosynthetic thylakoid membranes. The protein was identified by MS as extracellular calcium‐sensing receptor (CaS), previously reported to be located in the plasma membrane. By confocal laser scanning microscopy and subcellular fractionation, it was demonstrated that CaS localizes to the chloroplasts and is enriched in stroma thylakoids. The phosphorylation level of CaS responded strongly to light intensity. The light‐dependent thylakoid protein kinase STN8 is required for CaS phosphorylation. The phosphorylation site was mapped to the stroma‐exposed Thr380, located in a motif for interaction with 14‐3‐3 proteins and proteins with forkhead‐associated domains, which suggests the involvement of CaS in stress responses and signaling pathways. The knockout Arabidopsis lines revealed a significant role for CaS in plant growth and development.