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Updated: Jun 17, 2026
10:49
Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
Helix insertion into bilayers and the evolution of membrane proteins
1Department of Biology, University of Texas at San Antonio, 1 UTSA Circle, San Antonio, TX, 78249, USA. Robert.Renthal@UTSA.edu
Cellular and Molecular Life Sciences : CMLS
|December 30, 2009
Summary
Polytopic alpha-helical membrane proteins require assistance for insertion into lipid bilayers. This review explores their evolution, focusing on insertion mechanisms and potential pre-cellular ancestors.
Area of Science:
- Biochemistry
- Molecular Biology
- Evolutionary Biology
Background:
- Polytopic alpha-helical membrane proteins require existing membrane proteins for insertion.
- The evolutionary origins of these essential membrane proteins remain unclear.
Purpose of the Study:
- To review current knowledge on alpha-helix insertion into membranes.
- To gain insights into the evolution of membrane proteins.
Main Methods:
- Review of existing literature on membrane protein insertion.
- Analysis of the E. coli genome for potential ancestral proteins.
Main Results:
- Discusses various insertion mechanisms: translocon-dependent, antibiotic peptide/protein-mediated, in vitro, and chaperone-mediated.
- Identifies potential C-terminal tail-anchored (TA) proteins in E. coli as possible descendants of early insertion machinery.
Conclusions:
- Proposes that understanding insertion mechanisms provides clues to membrane protein evolution.
- Suggests pre-cellular mechanisms may have facilitated early polytopic alpha-helical membrane protein insertion.
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