Fig. 2: Representative regulatory mechanisms of STAT2-mediated ISG expression.
From: Stat2 stability regulation: an intersection between immunity and carcinogenesis
a ISG expression under normal physiological conditions. Without stimulation, STAT2 forms a tetramer complex with other STAT family members, including STAT1, 3, and 6, through their N-terminal domains, resulting in an anti-parallel structure. The complex induces basal expression of target genes. b ISG expression under physiological conditions after viral infection. When cells are infected with viruses, activated JAK1- and TYK2-mediated phosphorylation of STAT2 at tyrosine residues triggers the formation of a SH2–pTyr interaction-mediated homo- or heterodimer complex, which associates with IRF9 and results in the formation of the ISGF3 complex. The ISGF3 complex plays a key role in target gene expression in response to viral infection.
