Separation of Thylakoid Protein Complexes with Two-dimensional Native-PAGE

Area of Science:

• Plant molecular biology
• Protein biochemistry
• Photosynthesis research

Background:

• Thylakoid protein complexes exhibit hierarchical organization and dynamic interactions.
• Understanding these structures is crucial for elucidating photosynthetic efficiency.
• Existing methods may not fully resolve the complexity of these labile assemblies.

Purpose of the Study:

• To present a detailed methodology for analyzing thylakoid protein complexes.
• To enable the investigation of supercomplexes and subcomplexes within the thylakoid membrane.
• To provide a tool for studying labile protein interactions in *Arabidopsis thaliana*.

Main Methods:

• Sequential 2D-native gel electrophoresis (2D-BN-PAGE).
• Solubilization of protein super- and megacomplexes using mild digitonin detergent.
• Further dissociation of complexes with a stronger detergent, β-dodecyl maltoside (β-DM).
• Separation of protein complexes in two orthogonal dimensions based on size and native state.

Main Results:

• The described 2D-BN-PAGE method effectively separates and resolves thylakoid protein complexes.
• It allows for the dissociation of higher-order supercomplexes into smaller subcomplexes.
• The technique provides insights into the hierarchical composition and interactions of labile thylakoid proteins.

Conclusions:

• 2D-BN-PAGE is a powerful technique for dissecting the complexity of thylakoid protein assemblies.
• This method facilitates a deeper understanding of photosynthetic protein organization.
• The protocol is applicable to *Arabidopsis thaliana* and potentially other plant species.