The bimodal regulation of epidermal growth factor signaling by human Sprouty proteins
| Autor: | James E. Egan, Bogdan A. Yatsula, Dafna Bar-Sagi, Amy B. Hall |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
DNA
Complementary Time Factors Transcription Genetic MAP Kinase Signaling System Ubiquitin-Protein Ligases Blotting Western Regulator Down-Regulation CHO Cells Transfection Epidermal growth factor Cricetinae Proto-Oncogene Proteins Animals Drosophila Proteins Humans Cysteine Proto-Oncogene Proteins c-cbl Receptor Mitogen-Activated Protein Kinase 1 Multidisciplinary Epidermal Growth Factor biology Ubiquitin Kinase Intracellular Signaling Peptides and Proteins Membrane Proteins Proteins Biological Sciences Precipitin Tests Protein Structure Tertiary Cell biology ErbB Receptors Mitogen-activated protein kinase SPRY2 biology.protein Insect Proteins Signal transduction HeLa Cells Plasmids Signal Transduction Genetic screen |
| Zdroj: | Proceedings of the National Academy of Sciences. 99:6041-6046 |
| ISSN: | 1091-6490 0027-8424 |
| DOI: | 10.1073/pnas.052090899 |
| Popis: | Signal transduction through epidermal growth factor receptors (EGFRs) is essential for the growth and development of multicellular organisms. A genetic screen for regulators of EGFR signaling has led to the identification of Sprouty, a cell autonomous inhibitor of EGF signaling that is transcriptionally induced by the pathway. However, the molecular mechanisms by which Sprouty exerts its antagonistic effect remain largely unknown. Here we have used transient expression in human cells to investigate the functional properties of human Sprouty (hSpry) proteins. Ectopically expressed full-length hSpry1 and hSpry2 induce the potentiation of EGFR-mediated mitogen-activated protein (MAP) kinase activation. In contrast, truncation mutants of hSpry1 and hSpry2 containing the highly conserved carboxyl-terminal cysteine-rich domain inhibit EGF-induced MAP kinase activation. The potentiating effect of the full-length hSpry2 proteins on EGF signaling is mediated by the amino-terminal domain and results from the sequestration of c-Cbl, which in turn leads to the inhibition of EGFR ubiquitination and degradation. These results indicate that hSpry2 can function both as a negative and positive regulator of EGFR-mediated MAP kinase signaling in a domain-dependent fashion. A dual function of this kind could provide a mechanism for achieving proper balance between the activation and repression of EGFR signaling. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|