Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:6.3.2.19 (ubiquitin-protein ligase)
 799 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Aggregation of the high-affinity immunoglobulin E (IgE) receptor (FcepsilonRI) on mast cells induces a number of biochemical events, including protein-tyrosine phosphorylation leading to degranulation and multiple cytokine gene transcription. Here, we have demonstrated that a second member of the Cbl family of ubiquitin-protein ligase Cbl-b translocates into the lipid raft after FcepsilonRI engagement. Overexpression of Cbl-b in the lipid raft inhibits FcepsilonRI-mediated degranulation and cytokine gene transcription through the distinct mechanism. A point mutation of Cys373 in the RING finger domain of Cbl-b abrogates the suppression of FcepsilonRI-mediated degranulation but not cytokine gene transcription. The antigen-induced tyrosine phosphorylation of FcepsilonRI, Syk, phospholipase C-gamma (PLC-gamma), activation of c-Jun N-terminal kinase (JNK), extracellular signal regulated kinase (ERK), inhibitor of nuclear factor kappaB kinase (IKK), and Ca++ influx were all suppressed in the cells overexpressing Cbl-b in the lipid raft. In particular, the expression amount of Gab2 protein and thereby its FcepsilonRI-mediated tyrosine phosphorylation were dramatically down-regulated by ubiquitin-protein ligase activity of Cbl-b. These results suggest that Cbl-b is a negative regulator of both Lyn-Syk-LAT and Gab2mediated complementary signaling pathways in FcepsilonRI-mediated mast cell activation.
 ...
PMID:Negative regulation of FcepsilonRI-mediated mast cell activation by a ubiquitin-protein ligase Cbl-b. 1460 64

Perillyl alcohol (POH) is a naturally occurring terpene and a promising chemotherapeutic agent for glioblastoma multiform; yet, little is known about its molecular effects. Here we present results of a semi-quantitative proteomic analysis of A172 cells exposed to POH for different time-periods (1', 10', 30', 60', 4h, and 24h). The analysis identified more than 4000 proteins; which were clustered using PatternLab for proteomics and then linked to Ras signaling, tissue homeostasis, induction of apoptosis, metallopeptidase activity, and ubiquitin-protein ligase activity. Our results make available one of the most complete protein repositories for the A172. Moreover, we detected the phosphorylation of GSK3beta (Glycogen synthase kinase) and the inhibition of ERK's (extracellular signal regulated kinase) phosphorylation after 10', which suggests a new mechanism of POH's activation for apoptosis.
 ...
PMID:Dynamic proteomic overview of glioblastoma cells (A172) exposed to perillyl alcohol. 2008 44