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dc.contributor.authorMeisner, Herman
dc.contributor.authorDaga, Andrea
dc.contributor.authorBuxton, Joanne M.
dc.contributor.authorFernandez, Belen
dc.contributor.authorChawla, Anil
dc.contributor.authorBanerjee, Utpal
dc.contributor.authorCzech, Michael P.
dc.date2022-08-11T08:09:33.000
dc.date.accessioned2022-08-23T16:35:33Z
dc.date.available2022-08-23T16:35:33Z
dc.date.issued1997-04-01
dc.date.submitted2009-03-24
dc.identifier.citationMol Cell Biol. 1997 Apr;17(4):2217-25.
dc.identifier.issn0270-7306 (Print)
dc.identifier.pmid9121472
dc.identifier.urihttp://hdl.handle.net/20.500.14038/38587
dc.description.abstractThe human proto-oncogene product c-Cbl and a similar protein in Caenorhabditis elegans (Sli-1) contain a proline-rich COOH-terminal region that binds Src homology 3 (SH3) domains of proteins such as the adapter Grb2. Cb1-Grb2 complexes can be recruited to tyrosine-phosphorylated epidermal growth factor (EGF) receptors through the SH2 domain of Grb2. Here we identify by molecular cloning a Drosophila cDNA encoding a protein (Drosophila Cbl [D-Cbl]) that shows high sequence similarity to the N-terminal region of human c-Cbl but lacks proline-rich sequences and fails to bind Grb2. Nonetheless, in COS-1 cells, expression of hemagglutinin epitope-tagged D-Cbl results in its coimmunoprecipitation with EGF receptors in response to EGF. EGF also caused tyrosine phosphorylation of D-Cbl in such cells, but no association of phosphatidylinositol 3-kinase was detected in assays using anti-p85 antibody. A point mutation in D-Cbl (G305E) that suppresses the negative regulation of LET-23 by the Cbl homolog Sli-1 in C. elegans prevented tyrosine phosphorylation of D-Cbl as well as binding to the liganded EGF receptor in COS-1 cells. Colocalization of EGF receptors with both endogenous c-Cbl or expressed D-Cbl in endosomes of EGF-treated COS-1 cells is also demonstrated by immunofluorescence microscopy. In lysates of adult transgenic Drosophila melanogaster, GST-DCbl binds to the tyrosine-phosphorylated 150-kDa torso-DER chimeric receptor. Expression of D-Cbl directed by the sevenless enhancer in intact Drosophila compromises severely the development of the R7 photoreceptor neuron. These data suggest that despite the lack of Grb2 binding sites, D-Cbl functions as a negative regulator of receptor tyrosine kinase signaling in the Drosophila eye by a mechanism that involves its association with EGF receptors or other tyrosine kinases.
dc.language.isoen_US
dc.relation<a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&list_uids=9121472&dopt=Abstract">Link to Article in PubMed</a>
dc.subject*Adaptor Proteins, Signal Transducing
dc.subjectAmino Acid Sequence
dc.subjectAnimals
dc.subjectBase Sequence
dc.subjectBinding Sites
dc.subjectCaenorhabditis elegans
dc.subjectDNA Primers
dc.subjectDNA, Complementary
dc.subjectDrosophila melanogaster
dc.subjectGRB2 Adaptor Protein
dc.subjectHumans
dc.subjectMolecular Sequence Data
dc.subjectPhotoreceptors, Invertebrate
dc.subjectProtein Binding
dc.subjectProteins
dc.subjectProto-Oncogene Proteins
dc.subjectProto-Oncogene Proteins c-cbl
dc.subjectProto-Oncogenes
dc.subjectReceptor, Epidermal Growth Factor
dc.subjectSequence Homology, Amino Acid
dc.subject*Ubiquitin-Protein Ligases
dc.subjectsrc Homology Domains
dc.subjectLife Sciences
dc.subjectMedicine and Health Sciences
dc.titleInteractions of Drosophila Cbl with epidermal growth factor receptors and role of Cbl in R7 photoreceptor cell development
dc.typeJournal Article
dc.source.journaltitleMolecular and cellular biology
dc.source.volume17
dc.source.issue4
dc.identifier.legacyfulltexthttps://escholarship.umassmed.edu/cgi/viewcontent.cgi?article=2451&amp;context=oapubs&amp;unstamped=1
dc.identifier.legacycoverpagehttps://escholarship.umassmed.edu/oapubs/1452
dc.identifier.contextkey794949
refterms.dateFOA2022-08-23T16:35:34Z
html.description.abstract<p>The human proto-oncogene product c-Cbl and a similar protein in Caenorhabditis elegans (Sli-1) contain a proline-rich COOH-terminal region that binds Src homology 3 (SH3) domains of proteins such as the adapter Grb2. Cb1-Grb2 complexes can be recruited to tyrosine-phosphorylated epidermal growth factor (EGF) receptors through the SH2 domain of Grb2. Here we identify by molecular cloning a Drosophila cDNA encoding a protein (Drosophila Cbl [D-Cbl]) that shows high sequence similarity to the N-terminal region of human c-Cbl but lacks proline-rich sequences and fails to bind Grb2. Nonetheless, in COS-1 cells, expression of hemagglutinin epitope-tagged D-Cbl results in its coimmunoprecipitation with EGF receptors in response to EGF. EGF also caused tyrosine phosphorylation of D-Cbl in such cells, but no association of phosphatidylinositol 3-kinase was detected in assays using anti-p85 antibody. A point mutation in D-Cbl (G305E) that suppresses the negative regulation of LET-23 by the Cbl homolog Sli-1 in C. elegans prevented tyrosine phosphorylation of D-Cbl as well as binding to the liganded EGF receptor in COS-1 cells. Colocalization of EGF receptors with both endogenous c-Cbl or expressed D-Cbl in endosomes of EGF-treated COS-1 cells is also demonstrated by immunofluorescence microscopy. In lysates of adult transgenic Drosophila melanogaster, GST-DCbl binds to the tyrosine-phosphorylated 150-kDa torso-DER chimeric receptor. Expression of D-Cbl directed by the sevenless enhancer in intact Drosophila compromises severely the development of the R7 photoreceptor neuron. These data suggest that despite the lack of Grb2 binding sites, D-Cbl functions as a negative regulator of receptor tyrosine kinase signaling in the Drosophila eye by a mechanism that involves its association with EGF receptors or other tyrosine kinases.</p>
dc.identifier.submissionpathoapubs/1452
dc.contributor.departmentProgram in Molecular Medicine
dc.source.pages2217-25


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