The cAMP response element binding protein‐2 (CREB‐2) can interact with the C/EBP‐homologous protein (CHOP)

cAMP response element binding protein‐2 (CREB‐2) is a basic leucine zipper (bZIP) factor that was originally described as a repressor of CRE‐dependent transcription but that can also act as a transcriptional activator. Moreover, CREB‐2 is able to function in association with the viral Tax protein as an activator of the human T‐cell leukemia virus type I (HTLV‐I) promoter. Here we show that CREB‐2 is able to interact with C/EBP‐homologous protein (CHOP), a bZIP transcription factor known to inhibit CAAT/enhancer‐dependent transcription. Cotransfection of CHOP with CREB‐2 results in decreased activation driven by the cellular CRE motif or the HTLV‐I proximal Tax‐responsive element, confirming that CREB‐2 and CHOP can interact with each other in vivo.