Dataset Information

Mammalian LIN-7 PDZ proteins associate with beta-catenin at the cell-cell junctions of epithelia and neurons.

ABSTRACT: The heterotrimeric PDZ complex containing LIN-2, LIN-7 and LIN-10 is known to be involved in the organization of epithelial and neuronal junctions in Caenorhabditis elegans and mammals. We report here that mammalian LIN-7 PDZ proteins form a complex with cadherin and beta-catenin in epithelia and neurons. The association of LIN-7 with cadherin and beta-catenin is Ca(2+) dependent and is mediated by the direct binding of LIN-7 to the C-terminal PDZ target sequence of beta-catenin, as demonstrated by means of co-immunoprecipitation experiments and in vitro binding assays with the recombinant glutathione S-transferase:LIN-7A. The presence of beta-catenin at the junction is required in order to relocate LIN-7 from the cytosol to cadherin-mediated adhesions, thus indicating that LIN-7 junctional recruitment is beta-catenin dependent and that one functional role of the binding is to localize LIN-7. Moreover, when LIN-7 is present at the beta-catenin-containing junctions, it determines the accumulation of binding partners, thus suggesting the mechanism by which beta-catenin mediates the organization of the junctional domain.

SUBMITTER: Perego C

PROVIDER: S-EPMC306606 | biostudies-literature | 2000 Aug

REPOSITORIES: biostudies-literature

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Mammalian LIN-7 PDZ proteins associate with beta-catenin at the cell-cell junctions of epithelia and neurons.

Perego C C Vanoni C C Massari S S Longhi R R Pietrini G G

The EMBO journal 20000801 15

The heterotrimeric PDZ complex containing LIN-2, LIN-7 and LIN-10 is known to be involved in the organization of epithelial and neuronal junctions in Caenorhabditis elegans and mammals. We report here that mammalian LIN-7 PDZ proteins form a complex with cadherin and beta-catenin in epithelia and neurons. The association of LIN-7 with cadherin and beta-catenin is Ca(2+) dependent and is mediated by the direct binding of LIN-7 to the C-terminal PDZ target sequence of beta-catenin, as demonstrated ...[more]

PMID: 10921879

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Dataset Information

Mammalian LIN-7 PDZ proteins associate with beta-catenin at the cell-cell junctions of epithelia and neurons.

Publications

Mammalian LIN-7 PDZ proteins associate with beta-catenin at the cell-cell junctions of epithelia and neurons.

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