STAT1 alpha Recombinant Rabbit Monoclonal Antibody [SJ01-89] (ET1606-39)

UNIPROT #

P42224

PROTEIN NAME

STAT1 alpha

SYNONYMS

Signal transducer and activator of transcription 1 91kD antibody;CANDF7 antibody;DKFZp686B04100 antibody;IMD31A antibody;IMD31B antibody;IMD31C antibody;ISGF 3 antibody;ISGF-3 antibody;OTTHUMP00000163552 antibody;OTTHUMP00000165046 antibody;OTTHUMP00000165047 antibody;OTTHUMP00000205845 antibody;Signal transducer and activator of transcription 1 91kDa antibody;Signal transducer and activator of transcription 1 antibody;Signal transducer and activator of transcription 1, 91kD antibody;Signal transducer and activator of transcription 1-alpha/beta antibody;STAT 1 antibody;Stat1 antibody;STAT1_HUMAN antibody;STAT91 antibody;Transcription factor ISGF 3 components p91 p84 antibody;Transcription factor ISGF-3 components p91/p84 antibody

SEQUENCE SIMILARITIES

Belongs to the transcription factor STAT family.

POST-TRANSLATIONAL MODIFICATION

Phosphorylated on tyrosine and serine residues in response to a variety of cytokines/growth hormones including IFN-alpha, IFN-gamma, PDGF and EGF. Activated KIT promotes phosphorylation on tyrosine residues and subsequent translocation to the nucleus. Upon EGF stimulation, phosphorylation on Tyr-701 (lacking in beta form) by JAK1, JAK2 or TYK2 promotes dimerization and subsequent translocation to the nucleus. Growth hormone (GH) activates STAT1 signaling only via JAK2. Tyrosine phosphorylated in response to constitutively activated FGFR1, FGFR2, FGFR3 and FGFR4. Phosphorylation on Ser-727 by several kinases including MAPK14, ERK1/2 and CAMKII on IFN-gamma stimulation, regulates STAT1 transcriptional activity. Phosphorylation on Ser-727 promotes sumoylation though increasing interaction with PIAS. Phosphorylation on Ser-727 by PRKCD induces apoptosis in response to DNA-damaging agents. Phosphorylated on tyrosine residues when PTK2/FAK1 is activated; most likely this is catalyzed by a SRC family kinase. Dephosphorylation on tyrosine residues by PTPN2 negatively regulates interferon-mediated signaling. Upon viral infection or IFN induction, phosphorylation on Ser-708 occurs much later than phosphorylation on Tyr-701 and is required for the binding of ISGF3 on the ISREs of a subset of IFN-stimulated genes IKBKE-dependent. Phosphorylation at Tyr-701 and Ser-708 are mutually exclusive, phosphorylation at Ser-708 requires previous dephosphorylation of Tyr-701.; Sumoylated with SUMO1, SUMO2 and SUMO3. Sumoylation is enhanced by IFN-gamma-induced phosphorylation on Ser-727, and by interaction with PIAS proteins. Enhances the transactivation activity.; ISGylated.; Mono-ADP-ribosylated at Glu-657 and Glu-705 by PARP14; ADP-ribosylation prevents phosphorylation at Tyr-701. However, the role of ADP-ribosylation in the prevention of phosphorylation has been called into question and the lack of phosphorylation may be due to sumoylation of Lys-703.; Monomethylated at Lys-525 by SETD2; monomethylation is necessary for phosphorylation at Tyr-701, translocation into the nucleus and activation of the antiviral defense.

SUBCELLULAR LOCATION

Cytoplasm, Nucleus.

FUNCTION

Membrane receptor signaling by various ligands, including interferons and growth hormones such as EGF, induces activation of JAK kinases which then leads to tyrosine phosphorylation of the various Stat transcription factors. Stat1 and Stat2 are induced by IFN-α and form a heterodimer which is part of the ISGF3 transcription factor complex. Although early reports indicate Stat3 activation by EGF and IL-6, it has been shown that Stat3β appears to be activated by both while Stat3α is activated by EGF, but not by IL-6. Highest expression of Stat4 is seen in testis and myeloid cells. IL-12 has been identified as an activator of Stat4. Stat5 has been shown to be activated by Prolactin and by IL-3. Stat6 is involved in IL-4 activated signaling pathways. Mutations in the STAT1 molecule can be gain of function (GOF) or loss of function (LOF). Both of them can cause different phenotypes and symptoms. Recurring common infections are frequent in both GOF and LOF mutations. In humans STAT1 has been particularly under strong purifying selection when populations shifted from hunting and gathering to farming, because this went along with a change in the pathogen spectrum. STAT1 loss of function, therefore STAT1 deficiency can have many variants. There are two main genetic impairments that can cause response to interferons type I and III. First there can be autosomal recessive partial or even complete deficiency of STAT1. That causes intracellular bacterial diseases or viral infections and impaired IFN a, b, g and IL27 responses are diagnosed. In partial form there can also be found high levels of IFNg in blood serum. When tested from whole blood, monocytes do not respond to BCG and IFNg doses with IL-12 production. In complete recessive form there is a very low response to anti-viral and antimycotical medication. Second, partial STAT1 deficiency can also be an autosomal dominant mutation; phenotypically causing impaired IFNg responses and causing patients to suffer with selective intracellular bacterial diseases (MSMD).