Journal
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES
Volume 1808, Issue 1, Pages 41-46Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.bbamem.2010.09.018
Keywords
Membrane protein; Ion channel; Insertase; Cell-free synthesis; Liposome
Categories
Funding
- CNRS
- ANR [06-blan-0239-01]
Ask authors/readers for more resources
The mechanosensitive channel MscL of the plasma membrane of bacteria is a homopentamer involved in the protection of cells during osmotic downshock. The MscL protein, a polypeptide of 136 residues, was recently shown to require YidC to be inserted in the inner membrane of E. coli. The insertase YidC is a component of an insertion pathway conserved in bacteria, mitochondria and chloroplasts. MscL insertion was independent of the Sec translocon. Here, we report sucrose gradient centrifugation and freeze-etching microscopy experiments showing that MscL produced in a cell-free system complemented with preformed liposomes is able to insert directly in a pure lipid bilayer. Patch-clamp experiments performed with the resulting proteoliposomes showed that the protein was highly active. In vitro cell-free synthesis targeting to liposomes is a new promising expression system for membrane proteins, including those that might require an insertion machinery in vivo. Our results also question the real role of insertases such as YidC for membrane protein insertion in vivo. (C) 2010 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available