In the MLL/MEN fusion protein generated by this translocation, most of the coding region of the MEN protein, an RNA polymerase II elongation factor, is fused to the N-terminal third of the MLL protein, a possible transcriptional regulator.     ///    "Moreover, p53 coimmunoprecipitated with MLL/MEN as well as MEN, suggesting that the fusion protein binds to p53 through the MEN region. "    ///    "Although we could not demonstrate a functional difference between MLL/MEN and MEN in this study, these data suggest that the MLL/MEN chimeric transcriptional regulator may exert its oncogenic activity by inhibiting the function of the p53 tumor-suppressor protein by binding to it. "    ///    Transcriptional inhibition of p53 by the MLL/MEN chimeric protein found in myeloid leukemia.. 