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Updated: Jun 23, 2026

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features
Published on: March 16, 2022
Translocation of proteins through the Sec61 and SecYEG channels
Elisabet C Mandon1, Steven F Trueman, Reid Gilmore
1Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA. elisabet.mandon@umassmed.edu
Abstract:
The Sec61 and SecYEG translocation channels mediate the selective transport of proteins across the endoplasmic reticulum and bacterial inner membrane, respectively. These channels are also responsible for the integration of membrane proteins. To accomplish these two critical events in protein expression, the transport channels undergo conformational changes to permit the export of lumenal domains and the integration of transmembrane spans. Novel insight into how these channels open during protein translocation has been provided by a combination of the analysis of new channel structures, biochemical characterization of translocation intermediates, molecular dynamics simulations, and in vivo and in vitro analysis of structure-based Sec61 and SecY mutants.
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