Alanine Scanning Mutagenesis of the Second Extracellular Loop of Type 1 Corticotropin-Releasing Factor Receptor Revealed Residues Critical for Peptide Binding
| Autor: | T. Tselios, Iakovos Lazaridis, Achille Gravanis, Olga Rassouli, George Deraos, Kostas Gkountelias, Maria Venihaki, George Liapakis |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
endocrine system
Sauvagine Peptide Hormones Molecular Sequence Data Peptide Hormones/chemistry/genetics/metabolism Peptide binding Peptide Biology Binding Competitive Receptors Corticotropin-Releasing Hormone Amphibian Proteins Protein Binding/genetics Cell Line Protein Structure Tertiary/genetics Protein structure medicine Humans Mutagenesis Site-Directed Antalarmin Amino Acid Sequence Receptor Peptide sequence Pharmacology chemistry.chemical_classification Alanine/*genetics Alanine Receptors Corticotropin-Releasing Hormone/chemistry/genetics/*metabolism Amphibian Proteins/chemistry/genetics/metabolism Alanine scanning Molecular biology Peptide Fragments Peptide Fragments/chemistry/*genetics/*metabolism Protein Structure Tertiary chemistry Biochemistry Multigene Family Molecular Medicine Binding Competitive/genetics hormones hormone substitutes and hormone antagonists Protein Binding medicine.drug |
| Zdroj: | Molecular Pharmacology. 75:793-800 |
| ISSN: | 1521-0111 0026-895X |
| DOI: | 10.1124/mol.108.052423 |
| Popis: | Upon binding of the corticotropin-releasing factor (CRF) analog sauvagine to the type 1 CRF receptor (CRF(1)), the amino-terminal portion of the peptide has been shown to lie near Lys257 in the receptor's second extracellular loop (EL2). To test the hypothesis that EL2 residues play a role in the binding of sauvagine to CRF(1) we carried out an alanine-scanning mutagenesis study to determine the functional role of EL2 residues (Leu251 to Val266). Only the W259A, F260A, and W259A/F260A mutations reduced the binding affinity and potency of sauvagine. In contrast, these mutations did not seem to significantly alter the overall receptor conformation, in that they left unchanged the affinities of the ligands astressin and antalarmin that have been suggested to bind to different regions of CRF(1). The W259A, F260A, and W259A/F260A mutations also decreased the affinity of the endogenous ligand, CRF, implying that these residues may play a common important role in the binding of different peptides belonging to CRF family. Parallel amino acid deletions of the two peptides produced ligands with various affinities for wild-type CRF(1) compared with the W259A, F260A, and W259A/F260A mutants, supporting the interaction between the amino-terminal residues 8 to 10 of sauvagine and the corresponding region in CRF with EL2 of CRF(1). This is the first time that a specific region of CRF(1) has been implicated in detailed interactions between the receptor and the amino-terminal portion of peptides belonging to the CRF family. Mol Pharmacol |
| Databáze: | OpenAIRE |
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