Nuclear factors interacting with the mitogen-responsive regulatory region of the interleukin-2 gene.

We have investigated the interaction of nuclear factors with the regulatory region of the interleukin-2 (IL-2) growth factor gene, which is induced upon activation of T lymphocytes. The regulatory region of IL-2 has been defined previously on the basis of transient transfection experiments and DNase I hypersensitive site analyses. This region of about 275 base pairs contains both tissue-specific as well as activation-dependent elements. Here we demonstrate nuclear factors which bind in this region. Some of these interactions are cell type-specific and several depend on prior activation of cells. This suggests that multiple activation responsive elements reside in the IL-2 promoter region. The inducible DNA binding activity of one of the factors is dependent also on protein synthesis. We have established an in vitro transcription assay to assess functional requirements for these DNA binding proteins. The possible involvement of some of these factors in regulating other genes expressed in T cells is discussed.