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Mapping the ligand-binding site on a G protein-coupled receptor (GPCR) using genetically encoded photocrosslinkers.

ABSTRACT: We developed a general cell-based photocrosslinking approach to investigate the binding interfaces necessary for the formation of G protein-coupled receptor (GPCR) signaling complexes. The two photoactivatable unnatural amino acids p-benzoyl-L-phenylalanine and p-azido-L-phenylalanine were incorporated by amber codon suppression technology into CXC chemokine receptor 4 (CXCR4). We then probed the ligand-binding site for the HIV-1 coreceptor blocker, T140, using a fluorescein-labeled T140 analogue. Among eight amino acid positions tested, we found a unique UV-light-dependent crosslink specifically between residue 189 and T140. These results are evaluated with molecular modeling using the crystal structure of CXCR4 bound to CVX15.

SUBMITTER: Grunbeck A

PROVIDER: S-EPMC3099303 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Mapping the ligand-binding site on a G protein-coupled receptor (GPCR) using genetically encoded photocrosslinkers.

Grunbeck Amy A Huber Thomas T Sachdev Pallavi P Sakmar Thomas P TP

Biochemistry 20110407 17

We developed a general cell-based photocrosslinking approach to investigate the binding interfaces necessary for the formation of G protein-coupled receptor (GPCR) signaling complexes. The two photoactivatable unnatural amino acids p-benzoyl-L-phenylalanine and p-azido-L-phenylalanine were incorporated by amber codon suppression technology into CXC chemokine receptor 4 (CXCR4). We then probed the ligand-binding site for the HIV-1 coreceptor blocker, T140, using a fluorescein-labeled T140 analogu ...[more]

PMID: 21417335

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2020-09-21 | PXD020418 | Pride

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