A post-translational modification of the photosystem II subunit CP29 protects maize from cold stress.
The resistance of maize plants to cold stress has been associated with the appearance of a new chlorophyll a/b binding protein in the thylakoid membrane following chilling treatment in the light. The cold-induced protein has been isolated, characterized by amino acid sequencing, and pulse labeled with radioactive precursors, showing that it is the product of post-translational modification by phosphorylation of the minor chlorophyll a/b protein CP29 rather than the product of a cold-regulated gene or an unprocessed CP29 precursor. We show here that the CP29 kinase activity displays unique characteristics differing from previously described thylakoid kinases and is regulated by the redox state of a quinonic site. Finally, we show that maize plants unable to perform phosphorylation have enhanced sensitivity to cold-induced photoinhibition.
Bergantino
E
E
Dipartimento di Biologia, Università di Padova, Italy.
Dainese
P
P
Cerovic
Z
Z
Sechi
S
S
Bassi
R
R
D000595:Amino Acid Sequence; D003080:Cold Temperature; D006868:Hydrolysis; D007425:Intracellular Membranes / Q000378:metabolism; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D010756:Phosphoric Acids; D010766:Phosphorylation; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism*; D045332:Photosystem II Protein Complex; D011499:Protein Processing, Post-Translational; D016415:Sequence Alignment; D013050:Spectrometry, Fluorescence; D003313:Zea mays / Q000378:metabolism*
C069660:CP29 light harvesting complex; D045342:Light-Harvesting Protein Complexes; D010756:Phosphoric Acids; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; C030242:phosphoric acid