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Conformational antibody binding to a native, cell-free expressed GPCR in block copolymer membranes.

ABSTRACT: G-protein coupled receptors (GPCRs) play a key role in physiological processes and are attractive drug targets. Their biophysical characterization is, however, highly challenging because of their innate instability outside a stabilizing membrane and the difficulty of finding a suitable expression system. We here show the cell-free expression of a GPCR, CXCR4, and its direct embedding in diblock copolymer membranes. The polymer-stabilized CXCR4 is readily immobilized onto biosensor chips for label-free binding analysis. Kinetic characterization using a conformationally sensitive antibody shows the receptor to exist in the correctly folded conformation, showing binding behaviour that is commensurate with heterologously expressed CXCR4.

SUBMITTER: de Hoog HP

PROVIDER: S-EPMC4203850 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Conformational antibody binding to a native, cell-free expressed GPCR in block copolymer membranes.

de Hoog Hans-Peter M HP Lin JieRong Esther M EM Banerjee Sourabh S Décaillot Fabien M FM Nallani Madhavan M

PloS one 20141020 10

G-protein coupled receptors (GPCRs) play a key role in physiological processes and are attractive drug targets. Their biophysical characterization is, however, highly challenging because of their innate instability outside a stabilizing membrane and the difficulty of finding a suitable expression system. We here show the cell-free expression of a GPCR, CXCR4, and its direct embedding in diblock copolymer membranes. The polymer-stabilized CXCR4 is readily immobilized onto biosensor chips for labe ...[more]

PMID: 25329156

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