STAT2
Description
The STAT2 (signal transducer and activator of transcription 2) is a protein-coding gene located on chromosome 12.
Signal transducer and activator of transcription 2 is a protein that in humans is encoded by the STAT2 gene. It is a member of the STAT protein family. This protein is critical to the biological response of type I interferons (IFNs). It functions as a transcription factor downstream of type I interferons. STAT2 sequence identity between mouse and human is only 68%.
== Function == The protein encoded by this gene is a member of the STAT protein family. In response to cytokines and growth factors, STAT family members are phosphorylated by the receptor associated kinases, and then form homo- or heterodimers that translocate to the cell nucleus where they act as transcription activators. In response to IFN, this protein forms a complex with STAT1 and IFN regulatory factor family protein p48 (IRF9) and form ISGF-3 (IFN-stimulated gene factor-3), in which this protein acts as a transactivator, but lacks the ability to bind DNA directly. The protein mediates innate antiviral activity. Mutations in this gene result in Immunodeficiency 44.
STAT2 is a signal transducer and activator of transcription protein that mediates signaling by type I interferons (IFN-alpha and IFN-beta). Upon type I IFN binding to cell surface receptors, Jak kinases (TYK2 and JAK1) are activated, leading to tyrosine phosphorylation of STAT1 and STAT2. The phosphorylated STATs dimerize, associate with IRF9/ISGF3G to form a complex termed ISGF3 transcription factor, that enters the nucleus. ISGF3 binds to the IFN stimulated response element (ISRE) to activate the transcription of interferon stimulated genes, which drive the cell in an antiviral state. STAT2 also plays a negative feedback regulatory role in the type I interferon signaling by recruiting USP18 to the type I IFN receptor subunit IFNAR2 thereby mitigating the response to type I IFNs. STAT2 acts as a regulator of mitochondrial fission by modulating the phosphorylation of DNM1L at 'Ser-616' and 'Ser-637' which activate and inactivate the GTPase activity of DNM1L respectively.
STAT2 is also known as IMD44, ISGF-3, P113, PTORCH3, STAT113.