STAT2

STAT2 stands for "Signal transducer and activator of transcription 2". STAT2 is a transcription factor that is encoded in humans by the gene of the same name. STAT2 is a member of the STAT protein family. Members of this family are phosphorylated by receptor-associated kinases in response to various cytokines and growth factors. They then form homo- or heterodimers that translocate to the nucleus where they act as transcriptional activators. Related signaling pathways include the ERK-S and Erb-B signaling pathways.

Specifically, upon binding of type I IFN to cell surface receptors, activation of the JAK kinases TYK2 and JAK1 occurs. This process induces tyrosine phosphorylation of STAT1 and STAT2 and thus their activation. The phosphorylated STATs dimerize and associate with IRF9/ISGF3G. The complexes formed in each case are termed the ISGF3 transcription factor. This complex enters the nucleus where it binds to the IFN-stimulated response element(ISRE) of DNA. This activates the transcription of interferon-stimulated genes that put the cell into an antiviral state, for example.

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