Related Experiment Video
Updated: Jul 16, 2025
10:49
Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
13.3K
The insertase YidC chaperones the polytopic membrane protein MelB inserting and folding simultaneously from both
Nina Blaimschein1, Hariharan Parameswaran2, Gisela Nagler3
1Department of Biosystems Science and Engineering, Eidgenössische Technische Hochschule (ETH) Zürich, 4058 Basel, Basel-Stadt, Switzerland.
Structure (London, England : 1993)
|September 14, 2023
Summary
The insertase YidC aids the complex folding of membrane proteins like MelB. It guides protein segments into the membrane, preventing misfolding and ensuring cell viability.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Protein insertion and folding into cellular membranes are vital for cell function.
- The specific roles of insertases, such as YidC, in these processes are not fully understood.
Purpose of the Study:
- To investigate the mechanism by which the insertase YidC facilitates the insertion and folding of the polytopic melibiose permease (MelB) into membranes.
- To elucidate the contributions of YidC in guiding the stepwise folding and insertion of MelB.
Main Methods:
- In vivo experiments using conditional E. coli knockdowns.
- In vitro single-molecule force spectroscopy.
Main Results:
- MelB can insert into the membrane without SecYEG if YidC is present.
- MelB forms two folding cores, with segments inserting stepwise; however, misfolding is common.
- YidC significantly accelerates and chaperones the insertion and folding of MelB's folding cores.
Conclusions:
- YidC plays a crucial role in the stepwise insertion and folding of complex polytopic membrane proteins like MelB.
- YidC exhibits flexible chaperoning and insertase activities essential for membrane protein biogenesis.
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