We have previously shown that all-trans retinoic acid (RA) potentiates phorbol ester-mediated induction of plasminogen activator inhibitor-2 (PAI-2) gene transcription in human myelomonocytic leukemic cell lines.1 To identify the promoter elements required for RA induced potentiation, deletion mutants of the PAI-2 promoter fused to the chloramphenicol acetyl transferase (CAT) reporter gene were transiently expressed in U937 cells. These studies demonstrated that promoter sequences located between -1839 and -1063 were functionally relevant in generating this response. Exonuclease III protection analysis revealed that nuclear factors prepared from HL-60 cells bind to a region (-1659 to -1620), which contains a retinoic acid receptor element half-site separated by seven nucleotides from a glucocorticoid response element half-site. Gel retardation analysis using an oligonucleotide of PAI-2 promoter sequences -1660 to -1620 confirmed the specific binding of myelomonocytic leukemic cell factors to this region. Extracts prepared from RA stimulated and unstimulated cells resulted in the same pattern of complex formation, but the mobilities of the complexes were slightly different, which suggests RA binding to the complexes. Our results suggest the role of PAI-2 promoter elements in generating the response to RA. The binding characteristics of nuclear factors prepared from myelomonocytic cells to these sequences are indicative of RA receptor-DNA interaction.