CHARACTERIZATION OF NF(P), THE NUCLEAR FACTOR THAT INTERACTS WITH THEREGULATORY P SEQUENCE (5'-CGAAAATTTCC-3') OF THE HUMAN INTERLEUKIN-4 GENE - RELATIONSHIP TO NF-KAPPA-B AND NF-AT

The P sequence of the human interleukin-4 (IL-4) gene, which was defin ed as a responsive element for phorbol 12-myristate 13-acetate and cal cium ionophore (A23187) in Jurkat T cells, shares sequence similarity with the NF-kappa B and the NF-AT binding sites. We examined whether N F(P), a nuclear factor specific for the P sequence, is related to NF-k appa B and NF-AT. NF-kappa B (P65 or P65/P50 heterodimer) bound to the P sequence in electrophoretic mobility shift assays (EMSA) and activa ted transcription through the P sequence when expression plasmids were cotransfected with P sequence-driven reporter plasmids in Jurkat T ce lls. In EMSAs, NF(P) binding was inhibited by the unlabeled NF-AT bind ing site but not by the unlabeled AP1 binding site and purified NF-AT contained an activity that bound to the P sequence. Both mobility shif t and sequence specificity of NF-AT were similar to those of NF(P) and only a small amount of P65 was detected in NF(P) in crude nuclear ext racts. These results indicate that the component(s) of NF-AT has the p otential to reconstitute NF(P) whereas NF-kappa B alone cannot account for NF(P) in crude extracts. Unlike NF-AT, NF(P) does not contain AP1 as its DNA binding component. (C) 1994 Academic Press, Inc.