The STAT3 transcription factor is a critical signaling molecule for numerous cytokine and growth factor receptors and is essential for murine fetal development. As an 88 kD member of the STAT (Signal Transducer and Activator of Transcription) protein family, STAT3 is phosphorylated in response to cytokine receptor-associated kinase activity. STAT3 is activated primarily by phosphorylation at Tyr705, which induces its dimerization, nuclear translocation, and DNA binding. STAT3 can form both homodimers and heterodimers and is involved in the activation of genes required for cell growth and the regulation of apoptosis.
