A NOVEL PROMOTER SEQUENCE IS INVOLVED IN THE OXIDATIVE STRESS-INDUCEDEXPRESSION OF THE ADULT T-CELL LEUKEMIA-DERIVED FACTOR (ADF) HUMAN THIOREDOXIN (TRX) GENE/

Adult T cell leukemia-derived factor (ADF) is a human thioredoxin (Trx ) and is a disulfide reducing protein with various biological function s. We found that expression of the ADF/Trx gene was increased by oxida tive agents such as hydrogen peroxide, diamide and menadione in Jurkat cells, Analysis using a CAT expression vector plasmid under the contr ol of the ADF/Trx gene promoter revealed that CAT gene expression in J urkat cells was increased after exposure to oxidative agents, A series of deletion analyses showed that a region from -976 to -890 of the 5' flanking sequence was required for enhancement of ADF/Trx promoter ac tivity against the oxidative agents. Gel mobility shift assay revealed the specific DNA binding activities to the sequences from -953 to -93 0 in the nuclear extracts from the jurkat cells, The sequences in this region showed no homology with any known consensus sequences for DNA binding factors, It is suggested that ADF/Trx gene expression is enhan ced through a novel cis-acting regulatory element responsive for the o xidative stress and a new factor(s) is involved in this oxidative stre ss responsive element.