Rabbit Anti-Human SOCS3 polyclonal antibody for IHC-P. Accumulating evidence demonstrates that cytokine receptor signaling is negatively regulated by a family of Src homology 2 domain-containing adaptor molecules Termed SOCS (Suppressor of Cytokine Signaling) . To date, there are eight members of SOCS family have been recognized, they are SOCS-1, 2, 3, 4, 5, 6, 7 and CIS. Structurally the SOCS proteins are composed of an N-terminal region of variable length and amino acid composition, a central SH2 domain, and a previously unrecognized C-terminal motif that we have called the SOCS box. The SOCS proteins appear to form part of a classical negative feed back loop that regulates cytokine signal transduction via a STAT-induced transcriptional mechanism. Transcription of each of the SOCS genes occurs rapidly in vitro and in vivo in response to cytokines, and once produced, the various members of the SOCS family appear to inhibit signaling in different ways.