SOCS family proteins form part of a classical negative feedback system that regulates cytokine signal transduction. SOCS1 is involved in negative regulation of cytokines that signal through the JAK/STAT3 pathway. Through binding to JAKs, inhibits their kinase activity. In vitro, also suppresses Tec protein-tyrosine activity (By similarity). Appears to be a major regulator of signaling by interleukin 6 (IL6) and leukemia inhibitory factor (LIF). Regulates interferon-gamma mediated sensory neuron survival. Probable substrate recognition component of an ECS (Elongin BC-CUL2/5-SOCS-box protein) E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. Seems to recognize JAK2.
Specificity
Natural and recombinant Rat Suppressor of cytokine signaling 1
Subcellular Location
Nucleus Cytoplasmic vesicle Detected in perinuclear cytoplasmic vesicles upon interaction with FGFR3.
Interacts with multiple activated proteins of the tyrosine kinase signaling pathway including JAK family kinases, TEC, KIT, GRB2 and VAV (By similarity). Binding to JAKs is mediated through the KIR and SH2 domain to a phosphorylated tyrosine residue within the JAK JH1 domain (By similarity). Binds the SH3 domain of GRB2 via diproline determinants in the N-terminus, and the N-terminal regulatory domain of VAV (By similarity). Interacts with the Elongin BC complex (TCEB1 and TCEB2). Component of an ECS CBC(SOCS1) E3 ubiquitin-protein ligase complex which contains Elongin BC, CUL5, RBX1 and SOCS1. Interacts (via SH2 domain and SOCS box) with TRIM8 (By similarity). Interacts with CUL2. Interacts with AXL and FGFR3.