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In-Membrane Chemical Modification (IMCM) for Site-Specific Chromophore Labeling of GPCRs.

ABSTRACT: We present in-membrane chemical modification (IMCM) for obtaining selective chromophore labeling of intracellular surface cysteines in G-protein-coupled receptors (GPCRs) with minimal mutagenesis. This method takes advantage of the natural protection of most cysteines by the membrane environment. Practical use of IMCM is illustrated with the site-specific introduction of chromophores for NMR and fluorescence spectroscopy in the human ?-opioid receptor (KOR) and the human A2A adenosine receptor (A2A AR). IMCM is applicable to a wide range of in?vitro studies of GPCRs, including single-molecule spectroscopy, and is a promising platform for in-cell spectroscopy experiments.

SUBMITTER: Susac L

PROVIDER: S-EPMC4747426 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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In-Membrane Chemical Modification (IMCM) for Site-Specific Chromophore Labeling of GPCRs.

Sušac Lukas L O'Connor Casey C Stevens Raymond C RC Wüthrich Kurt K

Angewandte Chemie (International ed. in English) 20151106 50

We present in-membrane chemical modification (IMCM) for obtaining selective chromophore labeling of intracellular surface cysteines in G-protein-coupled receptors (GPCRs) with minimal mutagenesis. This method takes advantage of the natural protection of most cysteines by the membrane environment. Practical use of IMCM is illustrated with the site-specific introduction of chromophores for NMR and fluorescence spectroscopy in the human κ-opioid receptor (KOR) and the human A2A adenosine receptor ( ...[more]

PMID: 26545333

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