Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
40
pubmed:dateCreated
2002-9-30
pubmed:abstractText
Engagement of the high affinity receptor for IgE (FcepsilonRI) on mast cells and basophils results in FcepsilonRI beta and gamma subunits ubiquitination by an as yet undefined mechanism. Here we show that, upon FcepsilonRI engagement on RBL-2H3 cells Syk undergoes ubiquitination and Syk kinase activity is required for its own ubiquitination and that of FcepsilonRI beta and gamma chains. This requirement was demonstrated by overexpression of Syk wild-type or its kinase-dead mutant in RBL cells or using an Syk-deficient RBL-derived cell line transfected with wild-type or a kinase inactive form of Syk. We also identify c-Cbl as the E3 ligase responsible for both Syk and receptor ubiquitination. Furthermore, we demonstrate that Syk controls tyrosine phosphorylation of Syk-associated Cbl induced after receptor engagement. These data suggest a mutual regulation between Syk and Cbl activities. Finally, we show that a selective inhibitor of proteasome degradation induces persistence of tyrosine-phosphorylated receptor complexes, of activated Syk, and of FcepsilonRI-triggered degranulation. Our results provide a molecular mechanism for down-regulation of engaged receptor complexes by targeting ubiquitinated FcepsilonRI and activated Syk to the proteasome for degradation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/CBL protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Precursors, http://linkedlifedata.com/resource/pubmed/chemical/Intracellular Signaling Peptides..., http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/Oligopeptides, http://linkedlifedata.com/resource/pubmed/chemical/Protein Subunits, http://linkedlifedata.com/resource/pubmed/chemical/Protein-Tyrosine Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-cbl, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, IgE, http://linkedlifedata.com/resource/pubmed/chemical/Syk kinase, http://linkedlifedata.com/resource/pubmed/chemical/Thapsigargin, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitin-Protein Ligases, http://linkedlifedata.com/resource/pubmed/chemical/epoxomicin
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
4
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
36940-7
pubmed:dateRevised
2011-11-2
pubmed:meshHeading
pubmed-meshheading:12145291-Animals, pubmed-meshheading:12145291-Enzyme Precursors, pubmed-meshheading:12145291-Intracellular Signaling Peptides and Proteins, pubmed-meshheading:12145291-Kinetics, pubmed-meshheading:12145291-Leukemia, Basophilic, Acute, pubmed-meshheading:12145291-Ligands, pubmed-meshheading:12145291-Oligopeptides, pubmed-meshheading:12145291-Phosphorylation, pubmed-meshheading:12145291-Protein Subunits, pubmed-meshheading:12145291-Protein-Tyrosine Kinases, pubmed-meshheading:12145291-Proto-Oncogene Proteins, pubmed-meshheading:12145291-Proto-Oncogene Proteins c-cbl, pubmed-meshheading:12145291-Rats, pubmed-meshheading:12145291-Receptors, IgE, pubmed-meshheading:12145291-Thapsigargin, pubmed-meshheading:12145291-Tumor Cells, Cultured, pubmed-meshheading:12145291-Ubiquitin, pubmed-meshheading:12145291-Ubiquitin-Protein Ligases, pubmed-meshheading:12145291-Vaccinia virus
pubmed:year
2002
pubmed:articleTitle
Activation of Syk tyrosine kinase is required for c-Cbl-mediated ubiquitination of Fcepsilon RI and Syk in RBL cells.
pubmed:affiliation
Department of Experimental Medicine and Pathology, Institute Pasteur-Fondazione Cenci Bolognetti, University La Sapienza, Rome 00161, Italy. rosella.paolini@uniroma1.it
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't