rHuSTAT-3 5 µg

Rec. Human signal transducer and activator of transcription 3. Synonyms: Acute-phase response factor, STAT3, APRF, FLJ20882, MGC16063.

Rec. Human STAT3 encoding aa 50-240 expressed in E.coli, shows a 49kDa band on SDS-PAGE (including GST tag). STAT3 is tyrosine-phosphorylated and activated by a number of kinases. The binding of IL-6 family cytokines (including IL-6, oncostatin Mand leukemia inhibitory factor) to the gp130 receptor triggers STAT3 phosphorylation by JAK2. EGF-Rand certain other receptor tyrosine kinases, such as c-MET phosphorylate STAT3 in response to their ligands. STAT3 is also a target of the c-srcnon-receptor tyrosine kinase. STAT3-deficient mouse embryos can not develop beyond embryonic day 7 (E7.0), when gastrulation initiates. It appears that at these early stages of development, STAT3 activation is required for self-renewal of embryonic stem cells (ESCs). Indeed, LIF, which is supplied to ESC cultures to maintain their undifferentiatedstate, can be omitted if STAT3 is activated through some other means. Constitutive STAT3 activation is associated with various human cancers and commonly suggests poor prognosis. It has anti-apoptotic as well as proliferative effects. The STAT3 protein is transcription factor expressed in most cell types and is activated by multiple cytokines and growth factors including: IFN-a, IL-10, IL-6, IL-11, IL-12, IL-2, EGF etc. STAT3 binds to DNA as either a homodimer or as a heterodimer with STAT1. STAT3 interacts with the APRE (acute phase response element) and SIE (c-sis inducible element).