Identification of the Drosophila melanogaster homologue of the mammalian signal transducer protein, Vav.
Mammalian Vav signal transducer protein couples tyrosine kinase signals with the activation of the Rho/Rac GTPases, thus leading to cell differentiation and/or proliferation. We have isolated and characterized the DroVav gene, the homologue of hVav in Drosophila melanogaster. DroVav encodes a protein (793 residues) whose similarity with hVav is 47% and with hVav2 and hVav3 is 45%. DroVav preserves the unique, complex structure of hVav proteins, including the 'calponin homology', dbl homology, pleckstrin homology; SH2 and SH3 domains in addition to regions that are acidic rich, proline rich and cysteine rich. DroVav is located on the X chromosome in polytene interval 18A5;18B and is expressed in all stages of development and in all tissues. In mammalian cells, DroVav is tyrosine-phosphorylated in response to epidermal growth factor receptor (EGFR) induction; in vitro, the DroVav SH2 region is associated with tyrosine-phosphorylated EGFR. Thus, DroVav probably plays a pivotal role as a signal transducer protein during fruit fly development.
Dekel
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The Hubert H. Humphrey center for Experimental Medicine and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Russek
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Jones
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Mortin
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Katzav
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D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D018797:Cell Cycle Proteins; D002460:Cell Line; D004331:Drosophila melanogaster; D004625:Embryo, Nonmammalian; D066246:ErbB Receptors / Q000378:metabolism; D017403:In Situ Hybridization; D007814:Larva; D051379:Mice; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017434:Protein Structure, Tertiary; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D051567:Proto-Oncogene Proteins c-vav; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics*; D014960:X Chromosome
D018797:Cell Cycle Proteins; D011518:Proto-Oncogene Proteins; D051567:Proto-Oncogene Proteins c-vav; C496619:Vav1 protein, mouse; D066246:ErbB Receptors