PDZK1 Interacting Protein 1 (PDZK1IP1)

MAP17 is expressed at significant levels only in a single epithelial cell population, the proximal tubular epithelial cells of the kidney. By Western blot analysis, Kocher et al. (1996) determined that the DD96 protein product is a 17-kD membrane-associated protein, which they redesignated MAP17. By immunofluorescence studies, they localized MAP17 to the apical brush border membrane. In permeabilized cultured cell lines, MAP17 was associated with cell-cell membrane contact areas, indicating that MAP17 is an intracellular protein associated with the cytoplasmic aspect of the plasma membrane. Transfection of a full-length wildtype MAP17 cDNA clone into a colon carcinoma cell line markedly decreased cell proliferation in vitro and tumor growth in vivo.