A fusion gene, PAX5-PML, was found in acute lymphoblastic leukemia (ALL) with chromosomal translocation t(9;15)(p13;q24), but no functional analysis has been reported.     ///    PAX5-PML dominant negatively inhibited PAX5 transcriptional activity in the luciferase reporter assay and suppressed the expression of the PAX5 transcriptional targets in B-lymphoid cell line.     ///    "Additional experiments, including chromatin immunoprecipitation (ChIP) assay, suggested that PAX5-PML bound to the promoter through the association with PAX5 on the promoter. "    ///    PAX5-PML acts as a dual dominant-negative form of both PAX5 and PML..     ///    "On the other hand, coexpression of PAX5-PML inhibited PML sumoylation, disrupted PML nuclear bodies (NBs), and conferred apoptosis resistance on HeLa cells. "    ///    "Here, we demonstrate that PAX5-PML had a dominant-negative effect on both PAX5 and PML. "    ///    "Surprisingly, PAX5-PML hardly showed DNA-binding activity in vitro although it retained the DNA-binding domain of PAX5. "    ///    "Furthermore, treatment with arsenic trioxide (ATO) induced PML sumoylation and reconstitution of PML NBs, and overcame the anti-apoptotic effect of PAX5-PML in HeLa cells. "    ///    These data suggest the possible involvement of this fusion protein in the leukemogenesis of B-ALL in a dual dominant-negative manner and the possibility that ALL with PAX5-PML can be treated with ATO.. 