Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
2007-10-19
pubmed:abstractText
Aberrant activation of c-Kit is involved in a number of human diseases including cancers and leukemias. Certain receptor tyrosine kinases, such as epidermal growth factor receptor, have been shown to indirectly recruit Cbl through the adapter protein Grb2, leading to receptor ubiquitination and degradation. In order to study the role of Grb2 in c-Kit degradation, a series of mutations of the Grb2 binding sites in c-Kit were generated (Y703F, Y936F, and Y703F/Y936F). Since other signal transduction molecules are also known to bind Y703 and Y936, the more selective asparagine-to-alanine (N-to-A) mutants N705A, N938A, and N705A/N938A were generated. We could clearly demonstrate that binding of Grb2 was dependent on intact phosphorylation sites Y703 and Y936. Furthermore, we could demonstrate the presence of Cbl in a complex with Grb2 and c-Kit. Thus, Grb2 is able to indirectly recruit Cbl to c-Kit. In the N-to-A mutants, Cbl phosphorylation was strongly reduced, which correlated with reduced ubiquitination of c-Kit as well as decreased internalization and degradation of the receptor. Taken together, we have demonstrated that, in addition to its role in positive signaling via the Ras/Erk pathway, Grb2 mediates c-Kit degradation through recruitment of Cbl to c-Kit, leading to ubiquitination of c-Kit followed by internalization and degradation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0014-4827
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
313
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3935-42
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:17904548-Animals, pubmed-meshheading:17904548-Binding Sites, pubmed-meshheading:17904548-COS Cells, pubmed-meshheading:17904548-Cercopithecus aethiops, pubmed-meshheading:17904548-Down-Regulation, pubmed-meshheading:17904548-Endocytosis, pubmed-meshheading:17904548-Enzyme Activation, pubmed-meshheading:17904548-GRB2 Adaptor Protein, pubmed-meshheading:17904548-Humans, pubmed-meshheading:17904548-Mice, pubmed-meshheading:17904548-Mutation, pubmed-meshheading:17904548-Phosphorylation, pubmed-meshheading:17904548-Protein Binding, pubmed-meshheading:17904548-Protein Processing, Post-Translational, pubmed-meshheading:17904548-Protein Structure, Quaternary, pubmed-meshheading:17904548-Proto-Oncogene Proteins c-cbl, pubmed-meshheading:17904548-Proto-Oncogene Proteins c-kit, pubmed-meshheading:17904548-Signal Transduction, pubmed-meshheading:17904548-Tyrosine, pubmed-meshheading:17904548-Ubiquitination, pubmed-meshheading:17904548-src-Family Kinases
pubmed:year
2007
pubmed:articleTitle
Grb2 mediates negative regulation of stem cell factor receptor/c-Kit signaling by recruitment of Cbl.
pubmed:affiliation
Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Malmö University Hospital, SE-205 02 Malmö, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't