Figure 1From: Janus kinases and signal transducers and activators of transcription: their roles in cytokine signaling, development and immunoregulationStructure of Janus kinases (Jaks), signal transducers andactivators of transcription (Stats), and suppressors of cytokine signaling(SOCS). Regions of homology shared by Jaks have been termed Jak homology (JH)domains. JH1 is a kinase domain and JH2 is a pseudo-kinase domain. Theamino-terminus of the Jaks appears to be important for association withcytokine receptors subunits. Stats have a conserved tyrosine residue,phosphorylation of which allows Stat dimerization; a src homology(SH2) domain that mediates the dimerization; and an amino-terminal region thatis known to play a role in the dimerization of Stats dimer. The amino-terminal,carboxy-terminal and coiled-coil regions of Stats can interact with othertranscription factors. SOCS proteins share a similar strucuture with a centralSH2 domain, a region at the amino-terminus that is variable in both length andin amino acid sequence, and a region of homology at the carboxy-terminus termedthe 'SOCS box'.Back to article page