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Updated: Sep 13, 2025
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Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
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The EMC acts as a chaperone for membrane proteins
Carolin J Klose1,2, Kevin M Meighen-Berger1, Martin Kulke1
1Department of Bioscience, TUM School of Natural Sciences, Center for Functional Protein Assemblies (CPA), Technical University of Munich, Garching, Germany.
Nature Communications
|August 2, 2025
Summary
The ER membrane protein complex (EMC) acts as a chaperone, guiding membrane protein structure formation. This study identifies new EMC chaperone functions and develops a tool to predict its clients.
Area of Science:
- Cell biology
- Molecular biology
- Protein biogenesis
Background:
- Membrane protein biogenesis is complex and requires cellular machinery.
- The ER membrane protein complex (EMC) is known for its role in inserting transmembrane domains (TMDs).
Purpose of the Study:
- To characterize additional chaperone functions of the EMC beyond TMD insertion.
- To define client protein features for this EMC chaperone mode.
- To develop a predictive tool for EMC clients.
Main Methods:
- Interactomics studies to identify EMC-interacting proteins.
- Systematic studies using model proteins to define client features.
- Machine learning for client prediction model development.
Main Results:
- The EMC engages with TMDs through its EMC1 subunit, influencing their orientation in the lipid bilayer.
- Successful TMD assembly leads to reduced binding to the EMC chaperone site.
- A machine learning tool was developed for predicting EMC clients.
Conclusions:
- The EMC possesses a previously uncharacterized chaperone function crucial for membrane protein biogenesis.
- The EMC functions as a multifunctional molecular machine in the cell.
- Understanding EMC chaperone activity provides insights into protein folding and quality control.
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