Src-catalyzed phosphorylation of c-Cbl leads to the interdependent ubiquitination of both proteins.

Inhibition of Src family kinases blocks EGF-induced activation of Akt, phosphorylation of c-Cbl, and ubiquitination of the EGF receptor*

Fgr but not Syk tyrosine kinase is a target for beta 2 integrin-induced c-Cbl-mediated ubiquitination in adherent human neutrophils.

An early and critical event in beta(2) integrin signalling during neutrophil adhesion is activation of Src tyrosine kinases and Syk. In the present study, we report Src kinase-dependent beta(2) integrin-induced tyrosine phosphorylation of Cbl occurring in parallel with increased Cbl-associated tyrosine kinase activity. These events concurred with activation of Fgr and, surprisingly, also with d...

CIN85 phosphorylation is essential for EGFR ubiquitination and sorting into multivesicular bodies

Ubiquitination of the epidermal growth factor receptor (EGFR) by cbl and its cognate adaptor cbl-interacting protein of 85 kDa (CIN85) is known to play an essential role in directing this receptor to the lysosome for degradation. The mechanisms by which this ubiquitin modification is regulated are not fully defined, nor is it clear where this process occurs. In this study we show that EGFR acti...

Cbl-c Ubiquitin Ligase Activity Is Increased via the Interaction of Its RING Finger Domain with a LIM Domain of the Paxillin Homolog, Hic 5

Cbl proteins (Cbl, Cbl-b and Cbl-c) are ubiquitin ligases that are critical regulators of tyrosine kinase signaling. In this study we identify a new Cbl-c interacting protein, Hydrogen peroxide Induced Construct 5 (Hic-5). The two proteins interact through a novel interaction mediated by the RING finger of Cbl-c and the LIM2 domain of Hic-5. Further, this interaction is mediated and dependent o...

Cbl Associates with Pyk2 and Src to Regulate Src Kinase Activity, αvβ3 Integrin-Mediated Signaling, Cell Adhesion, and Osteoclast Motility

The signaling events downstream of integrins that regulate cell attachment and motility are only partially understood. Using osteoclasts and transfected 293 cells, we find that a molecular complex comprising Src, Pyk2, and Cbl functions to regulate cell adhesion and motility. The activation of integrin alpha(v)beta(3) induces the [Ca(2+)](i)-dependent phosphorylation of Pyk2 Y402, its associati...