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In Vitro Reconstitution of Light-harvesting Complexes of Plants and Green Algae
Published on: October 10, 2014
Lil3 assembles as chlorophyll-binding protein complex during deetiolation
Veronika Reisinger1, Matthias Plöscher, Lutz A Eichacker
1Ludwig-Maximilians-University Munich, Department Biology I, Menzingerstrasse 67, 80638 Munich, Germany.
FEBS Letters
|April 9, 2008
Summary
Light triggers deetiolation in plants, but how chlorophyll binds to proteins is unknown. This study reveals that the Lil3 protein forms new pigment-binding complexes in barley seedlings upon illumination, binding chlorophyll a and protochlorophyll a.
Area of Science:
- Plant Biology
- Photosynthesis Research
- Molecular Botany
Background:
- Dark-grown angiosperm seedlings exhibit etiolation and lack chlorophyll.
- Deetiolation, triggered by light, involves chlorophyll-dependent accumulation of photosynthetic machinery.
- The precise mechanism of chlorophyll transfer to binding proteins remains poorly understood.
Purpose of the Study:
- To investigate the de novo synthesis of pigment-binding protein complexes in barley seedlings upon light exposure.
- To identify the pigments involved and the specific protein subunits responsible for pigment binding during deetiolation.
Main Methods:
- Illumination of dark-grown barley seedlings.
- Auto-fluorescence tracking.
- Mass spectrometry analysis of protein complexes.
Main Results:
- Two novel pigment-binding protein complexes accumulate de novo after light exposure.
- These complexes bind chlorophyll a and protochlorophyll a.
- The protein subunit Lil3 is exclusively identified as the pigment-binding component in both complexes.
Conclusions:
- Light induces the formation of specific pigment-protein complexes in barley seedlings.
- The Lil3 protein plays a crucial role in binding chlorophyll a and protochlorophyll a during the deetiolation process.
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