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Detection of Protein Aggregation using Fluorescence Correlation Spectroscopy
Published on: April 25, 2021
Photosystem II antenna phosphorylation-dependent protein diffusion determined by fluorescence correlation
Masakazu Iwai1, Chan-Gi Pack, Yoshiko Takenaka
11] Live Cell Molecular Imaging Research Team, Extreme Photonics Research Group, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan [2] PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
Scientific Reports
|October 4, 2013
Summary
Light-harvesting antenna complex II (LHCII) phosphorylation increases protein diffusion in thylakoid membranes. This protein reorganization is key to how plants manage light energy under changing conditions.
Area of Science:
- Photosynthesis research
- Plant molecular biology
- Algal cell biology
Background:
- Chloroplast thylakoid membrane protein flexibility is vital for plant survival in fluctuating light.
- Light-harvesting antenna complex II (LHCII) phosphorylation drives protein reorganization to optimize energy conversion.
- Mechanisms of LHCII phosphorylation-induced light energy redistribution remain incompletely understood.
Purpose of the Study:
- To investigate the effect of LHCII phosphorylation on protein diffusion dynamics within thylakoid membranes.
- To elucidate the role of protein mobility in light energy redistribution in response to phosphorylation.
Main Methods:
- Utilized fluorescence correlation spectroscopy (FCS) to measure protein diffusion.
- Isolated thylakoid membranes from the green alga Chlamydomonas reinhardtii.
- Employed a phosphorylation-deficient mutant for verification.
Main Results:
- LHCII diffusion coefficient nearly doubled under phosphorylated conditions compared to dephosphorylated states.
- Observed a significant increase in LHCII protein mobility upon phosphorylation.
- Confirmed findings using a mutant lacking LHCII phosphorylation capability.
Conclusions:
- LHCII phosphorylation induces significant changes in protein diffusion rates.
- Protein reorganization, driven by altered diffusion, plays a crucial role in thylakoid light energy redistribution.
- Findings provide molecular insights into dynamic regulation of photosynthesis.
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