GPCR Engineering Yields High-Resolution Structural Insights into β 2 -Adrenergic Receptor Function
2007; American Association for the Advancement of Science; Volume: 318; Issue: 5854 Linguagem: Inglês
10.1126/science.1150609
ISSN1095-9203
AutoresDaniel M. Rosenbaum, Vadim Cherezov, Michael A. Hanson, Søren G. F. Rasmussen, Foon Sun Thian, Tong Sun Kobilka, Hee‐Jung Choi, Xiao-Jie Yao, William I. Weis, Raymond C. Stevens, Brian K. Kobilka,
Tópico(s)Pharmacological Effects and Assays
ResumoThe β 2 -adrenergic receptor (β 2 AR) is a well-studied prototype for heterotrimeric guanine nucleotide–binding protein (G protein)–coupled receptors (GPCRs) that respond to diffusible hormones and neurotransmitters. To overcome the structural flexibility of the β 2 AR and to facilitate its crystallization, we engineered a β 2 AR fusion protein in which T4 lysozyme (T4L) replaces most of the third intracellular loop of the GPCR (“β 2 AR-T4L”) and showed that this protein retains near-native pharmacologic properties. Analysis of adrenergic receptor ligand-binding mutants within the context of the reported high-resolution structure of β 2 AR-T4L provides insights into inverse-agonist binding and the structural changes required to accommodate catecholamine agonists. Amino acids known to regulate receptor function are linked through packing interactions and a network of hydrogen bonds, suggesting a conformational pathway from the ligand-binding pocket to regions that interact with G proteins.
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