The protein encoded by the STAT4 gene is a member of the STAT protein family of transcription factors. STAT4 is phosphorylated in response to interleukin-12 and is essential for IL12 signal transduction. Transactivation, electrophoretic mobility shift, and RNA interference analyses showed that Ikaros bound to the STAT4 promoter and was involved in regulation of STAT4 in human T cells.
