FIG. 1.

Analysis of HDM2 immunocomplex and identification of HDM2-L11 association. (A) HeLa cells were transiently transfected with plasmid DNA expressing HDM2. At 24 h after transfection, cells were metabolically labeled with [³⁵S]methionine and the lysates were immunoprecipitated with antibody to HDM2. Immunoprecipitated proteins were separated by SDS-PAGE and visualized by autoradiography. The molecular identities of L5 and L11 were determined by protein microsequencing following a preparative anti-HDM2 IP. The identity of the 32-kDa protein (p32) has not yet been established. (B) HDM2-associated p20 corresponds to human ribosomal protein L11. L11 protein contains a putative nuclear export signal (NES) and a nuclear and nucleolar localization signal (NLS/NoLS). Two peptide sequences were obtained from protein microsequencing; both matched perfectly with human L11.