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Updated: Apr 28, 2026

Determining Membrane Protein Topology Using Fluorescence Protease Protection FPP
Published on: April 20, 2015
Membrane topology of transmembrane proteins: determinants and experimental tools
1School of Biological Sciences, Seoul National University, Seoul 151-747, South Korea.
Abstract:
Membrane topology refers to the two-dimensional structural information of a membrane protein that indicates the number of transmembrane (TM) segments and the orientation of soluble domains relative to the plane of the membrane. Since membrane proteins are co-translationally translocated across and inserted into the membrane, the TM segments orient themselves properly in an early stage of membrane protein biogenesis. Each membrane protein must contain some topogenic signals, but the translocation components and the membrane environment also influence the membrane topology of proteins. We discuss the factors that affect membrane protein orientation and have listed available experimental tools that can be used in determining membrane protein topology.
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