INTERLEUKIN-4-INDUCED STAT6 RECOGNIZES AND ACTIVATES A TARGET SITE INTHE PROMOTER OF THE INTERLEUKIN-4 RECEPTOR GENE

This study addresses the function of STAT6 in interleukin-4-stimulated gene expression. A specific STAT6 DNA-binding target site has been id entified in the promoter of the interleukin-4 receptor gene, and STAT6 is shown to be involved in mediating activation of gene expression vi a this site. STAT6 can mediate transcription of a heterologous reporte r gene construct containing the interleukin-4 receptor STAT6 binding s ite. In addition, evidence is provided that demonstrates a distinct ef fect of STAT6 DNA binding specificity on transcriptional regulation si nce transcription was not stimulated from a competent but different DN A binding site. To confirm the role of STAT6 in gene activation, STAT6 mutant proteins were generated and analyzed for their ability to func tion in interleukin-4-induced transcription. Although the interleukin- 2 gamma chain receptor subunit has been demonstrated to be a component of the interleukin-4 receptor, it is not required for specific gene a ctivation.