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. 2017 Aug 4;8(36):60710–60722. doi: 10.18632/oncotarget.19940

Figure 1. The classification and domain structure of the SOCS protein family.

Figure 1

All of the eight SOCS-family members have a central SH2 domain,an amino-terminal domain of variable length and a 40-amino-acid motif at the carboxy terminus that is known as the SOCS box. Although there is sequence homology between all family members-particularly in the SOCS box and SH2 domain-CIS and SOCS2, SOCS1 and SOCS3, SOCS4 and SOCS5, and SOCS6 and SOCS7 have marked pair-wise homology across the entire protein sequence, as indicated. In SOCS1 and SOCS3, a kinase-inhibitory region (K) adjacent to the SH2 domain that is required for high-affinity binding to Jaks and the inhibition of kinase activity has also been defined. The alternative nomenclature for each SOCS protein is given in parentheses. CIS, cytokine-induced SH2 protein; JAB, Janus kinase(Jak)-binding protein; NAP4, Nck, Ash and phospholipase-C binding protein; SH2, SRC-homology 2; SOCS, suppressor of cytokine signalling; SSI, Stat-induced Stat inhibitor; Stat, signal transducer and activator of transcription.