Simultaneous regulation of antenna size and photosystem I/II stoichiometry in Arabidopsis thaliana

• Published in: Planta Vol. 244; no. 5; pp. 1041 - 1053
• Main Authors: Jia, Ting, Ito, Hisashi, Tanaka, Ayumi
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Science + Business Media 01.11.2016; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Acclimatization; Agriculture; Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Biomedical and Life Sciences; Chlorophyll; Chlorophyll - metabolism; Chlorophyll A; Chromatography, High Pressure Liquid; Ecology; Electrophoresis, Polyacrylamide Gel; Environmental changes; Environmental conditions; Fluorescence; Forestry; Gene Expression Regulation, Plant; Immunoblotting; Life Sciences; Light-Harvesting Protein Complexes - metabolism; Models, Biological; ORIGINAL ARTICLE; Oxygenases - genetics; Oxygenases - metabolism; Photosynthesis; Photosystem I Protein Complex - metabolism; Photosystem II Protein Complex - metabolism; Plant Sciences; RNA, Messenger - genetics; RNA, Messenger - metabolism; Substrate Specificity; Temperature; Transformation, Genetic; Chlorophyll; oxygenase; Photosystem stoichiometry; Peripheral antenna complexes; Photosystem reassembly; Chlorophyll b; Chlorophyll a oxygenase
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/s00425-016-2568-5

Regulation of antenna size and photosystem I/II stoichiometry is an indispensable strategy for plants to acclimate to changes to light environments. When plants grown in high-light conditions are transferred to low-light conditions, the peripheral antennae of photosystems are enlarged. A change in the photosystem I/II ratio is also observed under the same light conditions. However, our knowledge of the correlation between antenna size modulation and variation in photosystem I/II stoichiometry remains limited. In this study, chlorophyll a oxygenase was transiently induced in Arabidopsis thaliana chlorophyll b-less mutants, ch1-1, to alter the antenna size without changing environmental conditions. In addition to the accumulation of chlorophyll b, the levels of the peripheral antenna complexes of both photosystems gradually increased, and these were assembled to the core antenna of both photosystems. However, the antenna size of photosystem II was greater than that of photosystem I. Immunoblot analysis of core antenna proteins showed that the number of photosystem I increased, but not that of photosystem II, resulting in an increase in the photosystem I/II ratio. These results clearly indicate that antenna size adjustment was coupled with changes in photosystem I/II stoichiometry. Based on these results, the physiological importance of simultaneous regulation of antenna size and photosystem I/II stoichiometry is discussed in relation to acclimation to light conditions.