Fig. 3.

SOCS proteins in regulation of RTKs: SOCS family proteins associate with RTKs in response to respective ligand stimulation. This association is mediated through the SH2 domain of SOCS and phosphotyrosine residues of receptors. Activation of receptors leads to transcriptional activation of SOCS and which in turn then negatively regulates receptor signaling by SOCS-box-mediated ubiquitination and degradation of receptor. SOCS proteins also have the ability to recruit signaling proteins through N-terminal proline rich region. This interaction probably accelerates receptor signaling