IndraLab
Statements
"Ligand binding to EGFR also leads to rapid internalization and proteosomal/lysosomal degradation of the receptors. This process results in a dramatic downregulation of both total and cell surface receptors. EGF-induced degradation of EGFR is thought to be initiated by phosphorylation of tyrosine 1045 of the receptor followed by binding of Cbl adaptor proteins and ubiquitination of the receptor. Internalized EGFR is transported to early endosomes where receptor-ligand complexes are sorted for either degradation or recycling to the cell surface."
"Here we describe that overexpression of cbl-b, a homologue of the c-cbl protooncogene, inhibits EGFR-induced apoptosis in MDA-MB-468 breast cancer cells. Overexpression of cbl-b results in a shortened duration of EGFR activation upon EGF stimulation. This is demonstrated by decreased amounts of phosphorylated EGFR as well as by inhibition of multiple downstream signaling pathways. The inhibition of signaling by cbl-b results from increased ubiquitination and degradation of the activated EGFR."
"RNF126 and Rabring7 associate with the EGFR through a ubiquitin-binding zinc finger domain and both E3 ubiquitin ligases promote ubiquitylation of EGFR. In HeLa cells depleted of either RNF126 or Rabring7 the EGFR is retained in a late endocytic compartment and is inefficiently degraded."
"USP8 is known to deubiquitinate EGFR in response to ligand stimulation. USP8 depletion accelerates receptor turnover, whereas loss of hepatocyte growth factor-regulated substrate (Hrs) rescues this phenotype, indicating that USP8 protects EGFR from degradation via an Hrs-dependent pathway. [..]As EGFR stabilization against lysosomal turnover requires deubiquitination by USP8."
"SOCS5 Can Physically Associate with the EGFR. The complex recruited by SOCS proteins is composed of ElonginBC, Cullin, and Roc1 (15, 16). Together, this complex has E3 ubiquitin ligase activity. We suspect that the role of the SB domain is to mediate coupling of EGFR with the Elongin-Cullin-Roc E3 ubiquitin ligase complex, resulting in enhanced EGFR degradation."
"RNF126 and Rabring7 associate with the EGFR through a ubiquitin-binding zinc finger domain and both E3 ubiquitin ligases promote ubiquitylation of EGFR. In HeLa cells depleted of either RNF126 or Rabring7 the EGFR is retained in a late endocytic compartment and is inefficiently degraded."