To elucidate the structure characteristic, regulation of expression and the potential function ofJWA— a novel retinoic acid responsible and cytoskeleton associate gene, a ratJWA homologue gene and a 621-bpJWA promoter fragment were cloned and analyzed. Using reverse transcription-polymerase chain reaction (RT-PCR),JWA mRNA expression in NIH3T3, K562 and human primary acute promyelocytic leukaemia (APL) cells have been investigated after treatment with all trans retinoic acid (ATRA), N-4-hydroxyphenyl-retinamide (4HPR), arsenic trioxide (As2O3), Phorbol-12-myristate-13-acetate (TPA) and dimethyl sulfoxide (DMSO). The results showed that there is a complete TPA responsive element (TRE) existed in the promoter ofJWA at 437 to 443 bp; ratJWA homologue gene showed that there are four nucleotides different from humanJWA within coding region. After treatment with TPA, an uneven pattern ofJWA transcription existed in different cell lines, suggesting that even TPA induces cell differentiation in different cell lines, and it may be referred to different signal pathways. In ATRA pretreated APL cells, all the above chemicals induce cellular differentiation and down regulateJWA transcriptionin vitro. This suggests that pretreatment of ATRA on APL cells seems a precondition for turning onJWA involved signal pathway.