A family of proteins (signal transducers and activators of transcription) that interact with receptors through a phosphotyrosine/SH2 domain interaction, are then phosphorylated by JAKs, dimerize, and translocate to the nucleus where they act as transcription factors. Many STATs are known with varying receptor specificity and differences in the binding sites on DNA to which they bind, e.g. STAT1 is activated by interferon-α, interferon-γ, EGF, PDGF, and IL-6 whereas STAT2 is only activated by interferon-α. STAT3, STAT5, and STAT6 are involved in signalling from the leptin receptor, as well as from various interleukin receptors. Mutations in STAT1 affect innate immunity to viruses and mycobacteria. Mutations in STAT3 are associated with hyper-IgE syndrome (Job's syndrome). See signal-transducing adaptor proteins.
Subjects: Medicine and Health.