Importance of the Carboxy-Terminus of the CXCR2 for Signal Transduction
| Autor: | Meike Burger, Robert C. Hoch, Zenaida G. Oades, Hiroshi Takamori, Ingrid U. Schraufstatter |
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| Rok vydání: | 1998 |
| Předmět: |
Molecular Sequence Data
Mutant Biophysics Biology Ligands Sulfur Radioisotopes Biochemistry Receptors Interleukin-8B Serine Tumor Cells Cultured Animals Amino Acid Sequence Phosphorylation Receptor Molecular Biology Sequence Deletion Alanine Binding Sites Interleukin-8 Wild type Receptors Interleukin Cell Biology Transfection Ligand (biochemistry) Molecular biology Rats Leukemia Basophilic Acute Guanosine 5'-O-(3-Thiotriphosphate) Mutagenesis Site-Directed Receptors Chemokine Signal transduction Signal Transduction |
| Zdroj: | Biochemical and Biophysical Research Communications. 244:243-248 |
| ISSN: | 0006-291X |
| DOI: | 10.1006/bbrc.1998.8246 |
| Popis: | The CXCR2 is phosphorylated at the C-terminal intracytoplasmic portion within 15 sec following the addition of IL-8 or MGSA. Cells transfected with a truncated form of the receptor missing the last 12 amino acids (T3) showed normal binding affinity, but were no longer phosphorylated; individual alanine replacement indicated that Ser346 and 348 were the primary sites of phosphorylation. In studies of the importance of phosphorylation in CXCR2 desensitization, cells expressing wild type CXCR2 lost GTP gamma S binding above basal rate after the first exposure to IL-8, while cells with the T3 mutant retained 60% of their capacity to induce GTP gamma S exchange upon a second exposure to IL-8. In contrast, receptor internalization was not affected by the loss of phosphorylation of the T3 mutant. Further receptor truncation led to decreasing binding affinities for IL-8 and MGSA and a decreased rate of GTP gamma S exchange following addition of excess ligand which suggests involvement of this region in G-protein coupling. |
| Databáze: | OpenAIRE |
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