Phosphorylation of human growth hormone by the epidermal growth factor-stimulated tyrosine kinase
| Autor: | Graham S. Baldwin, Boris Grego, Francis J. Morgan, M. T. W. Hearn, J. A. Knesel, Richard J. Simpson |
|---|---|
| Rok vydání: | 1983 |
| Předmět: |
Protein tyrosine phosphatase
SH2 domain Receptor tyrosine kinase Cell Line chemistry.chemical_compound Epidermal growth factor Humans Trypsin Protein phosphorylation Amino Acid Sequence Phosphorylation Multidisciplinary Epidermal Growth Factor biology Tyrosine phosphorylation Protein-Tyrosine Kinases Molecular biology Peptide Fragments Kinetics chemistry Biochemistry Growth Hormone Carcinoma Squamous Cell biology.protein Protein Kinases Tyrosine kinase hormones hormone substitutes and hormone antagonists Platelet-derived growth factor receptor Research Article |
| Zdroj: | Proceedings of the National Academy of Sciences. 80:5276-5280 |
| ISSN: | 1091-6490 0027-8424 |
| DOI: | 10.1073/pnas.80.17.5276 |
| Popis: | In the present study, we have demonstrated that human growth hormone (hGH) can be phosphorylated by the epidermal growth factor (EGF)-stimulated tyrosine kinase of A431 cell membranes. Phosphotyrosine was the predominant phosphoamino acid released from phosphorylated hGH on partial acid hydrolysis. All five tyrosine-containing tryptic peptides of hGH are also phosphorylated by the EGF-stimulated tyrosine kinase. The highest phosphate incorporation was found for peptide T4 (residues 20-38), which is distinguished by a high frequency of acidic amino acids. The phosphorylated peptides have been characterized by HPLC and two-dimensional mapping on paper. Comparison with the labeled peptides obtained on tryptic digestion of phosphorylated hGH suggests that tyrosine phosphorylation is restricted to two tryptic peptides, T4 (tyrosine-28 or -35) and T6 (tyrosine-42). It is suggested that the absence of early insulin-like activity in the naturally occurring Mr 20,000 variant of hGH, which has an internal deletion spanning residues 32-46, may be a consequence of the loss of the tyrosine phosphorylation sites at residues 35 and 42. |
| Databáze: | OpenAIRE |
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