The STAT3 DNA-binding domain mediates interaction with NF-κB p65 and inducible nitric oxide synthase transrepression in mesangial cells

Signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappaB (NF-kappaB) are important transcription factors involved in glomerulonephritis and other inflammatory processes, including transcription of the inducible nitric oxide synthase (iNOS) gene. The ability of STAT3 to inteiact physically with NF-kappaB p65 in alornerular rnesangial cells and thereby to inhibit NF-kappaB-inediated transactivation of the iNOS gene was demonstrated previously. STAT3 is a modular protein with several structurally and functionally defined domains. For defining STAT3 domains that interact with NF-