Biolegend, 941208, Alexa Fluor® 488 anti-STAT4 Phospho (Tyr693) Antibody

The signal transducer and activator of transcription (STAT) family of transcription factors are DNA-binding proteins required for transcriptional regulation of several cellular and physiological processes in response to cytokine and growth factor stimulation. Inactive STAT proteins are present as cytosolic monomers. C-terminal tyrosine phosphorylation by upstream Janus kinases results in STAT dimerization, translocation to the nucleus, and increased affinity for response elements found in the regulatory promoter of STAT target genes. In contrast to most other members of the STAT family, STAT4 expression is restricted to hematopoietic cells and responds to fewer cytokines, such as IL-12 and IL-2. STAT4, which requires phosphorylation at tyrosine 693 for activation, plays a pivotal role in the differentiation and proliferation of Th1 and Th17 cells, both of which are crucial effectors of chronic autoimmune disorders. In natural killer cells, STAT4 is required for normal development, maturation, and activation. Single nucleotide polymorphisms of STAT4 are implicated in the pathogenesis of systemic lupus erythematosis and rheumatoid arthritis, and are linked with increased risk of hepatocellular carcinoma.