title: 5T4 interacts with TIP-2/GIPC, a PDZ protein, with implications for metastasis.
abstract: Overexpression of the 5T4 transmembrane glycoprotein can have marked effects on both the actin cytoskeleton and cell migration. Using a yeast two-hybrid approach, we describe a novel interaction between 5T4 and TIP-2/GIPC, a cytoplasmic interacting protein containing a PDZ domain. The cytoplasmic tail of 5T4 contains a class I PDZ-binding motif (Ser-Asp-Val) and we demonstrate that this region, in particular the terminal valine, is required for 5T4 interaction with TIP-2/GIPC. HeLa cells expressing hemagglutinin-tagged TIP-2/GIPC (HA-TIP-2/GIPC) have an altered distribution of endogenous 5T4, which colocalizes with HA-TIP-2/GIPC, thus supporting an interaction. Furthermore, TIP-2/GIPC can be coimmunoprecipitated with 5T4 from HeLa cell lysates. Identification of the 5T4 and TIP-2/GIPC interaction provides the first link between 5T4 and the actin cytoskeleton. Since other proteins, like 5T4, associate with TIP-2/GIPC and are linked with cancer, we explore the possibility that TIP-2/GIPC may be a common factor involved in the cancer process.
authors.affiliation: CRC Immunology Group, CRC Molecular Biology Group, The Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester, M20 4BX, United Kingdom.
authors.forename: Abida
authors.initials: A
authors.lastname: Awan
authors.forename: Melinda R
authors.initials: MR
authors.lastname: Lucic
authors.forename: David M
authors.initials: DM
authors.lastname: Shaw
authors.forename: Freda
authors.initials: F
authors.lastname: Sheppard
authors.forename: Caroline
authors.initials: C
authors.lastname: Westwater
authors.forename: Steve A
authors.initials: SA
authors.lastname: Lyons
authors.forename: Peter L
authors.initials: PL
authors.lastname: Stern
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000951:Antigens, Neoplasm / Q000737:chemistry / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009362:Neoplasm Metastasis; D009479:Neuropeptides / Q000737:chemistry / Q000378:metabolism*; D011233:Precipitin Tests; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000951:Antigens, Neoplasm; D002352:Carrier Proteins; C492009:GIPC1 protein, human; D008562:Membrane Glycoproteins; D009479:Neuropeptides; C063709:trophoblastic glycoprotein 5T4, human