Display Settings:

Format

Send to:

Choose Destination
    Biochem Biophys Res Commun. 2003 Mar 14;302(3):454-61.

    C-terminal phosphorylation of MRP2 modulates its interaction with PDZ proteins.

    Source

    Department of Molecular Cell Biology, Membrane Research Group of the Hungarian Academy of Sciences, National Medical Center, Diószegi u. 64, 1113 Budapest, Hungary.

    Abstract

    MRP2, a member of the ABC protein superfamily, functions as an ATP-dependent export pump for anionic conjugates in the apical membranes of epithelial cells. It has been reported that the trafficking of MRP2 is modulated by PKC. Adjacent to the C-terminal PDZ binding motif, which may be involved in the targeting of MRP2, we found a potential PKC phosphorylation site (Ser(1542)). Therefore, we examined the interaction of MRP2 and its phosphorylation-mimicking mutants with different PDZ proteins (EBP50, E3KARP, PDZK1, IKEPP, beta2-syntrophin, and SAP-97). The binding of these PDZ proteins to CFTR and ABCA1, other ABC proteins, possessing PDZ binding motif, was also studied. We observed a strong binding of apically localized PDZ proteins to both MRP2 and CFTR, whereas beta2-syntrophin exhibited binding only to ABCA1. The phosphorylation-mimicking MRP2 mutant and a phosphorylated C-terminal MRP2 peptide showed significantly increased binding to IKEPP, EBP50, and both individual PDZ domains of EBP50. Our results suggest that phosphorylation of the MRP2 PDZ binding motif has a profound effect on the PDZ binding of MRP2.

    PMID:
    12615054
    [PubMed - indexed for MEDLINE]

      Supplemental Content

      Click here to read

      Recent activity

      Your browsing activity is empty.

      Activity recording is turned off.

      Turn recording back on

      See more...
      Write to the Help Desk