Modification of the composition of polycystin-1 multiprotein complexes by calcium and tyrosine phosphorylation

Biochim Biophys Acta. 2000 Dec 15;1535(1):21-35. doi: 10.1016/s0925-4439(00)00079-x.


Mutations in the PKD1 gene are responsible for >85% of autosomal dominant polycystic kidney disease (ADPKD). The protein product of PKD1, polycystin-1, is a large, modular membrane protein, with putative ligand-binding motifs in the extracelluar N-terminal portion, 9-11 transmembrane domains and an intracellular C-terminal portion with phosphorylation sites. A role for polycystin-1 as a cell surface receptor involved in cell-matrix and cell-cell interactions has been proposed. In this study, we have analyzed polycystin-1 and associated protein distribution in normal human epithelial cells and examined the role of cell-matrix versus cell-cell interactions in regulation of the assembly of polycystin-1 multiprotein complexes. Immunocytochemistry, sucrose density gradient sedimentation, co-immunoprecipitation analyses and in vitro binding assays have shown that polycystin-1 associates with the focal adhesion proteins talin, vinculin, p130Cas, FAK, alpha-actinin, paxillin and pp60c-src in subconfluent normal human fetal collecting tubule (HFCT) epithelia when cell-matrix interactions predominate. Polycystin-1 also forms higher S value complexes with the cell-cell adherens junction proteins E-cadherin, beta- and gamma-catenins in confluent cultures when cell-cell interactions are predominant. Polycystin-1 multiprotein complexes can be disrupted by cytochalasin D but not by colchicine, suggesting involvement of the actin cytoskeleton. Although inhibition of tyrosine phosphorylation by tyrphostin inhibits polycystin-1-FAK interactions, E-cadherin interactions are enhanced. High calcium treatment also increases polycystin-1-E-cadherin interactions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cadherins / chemistry
  • Calcium / pharmacology
  • Cell Adhesion / drug effects
  • Cell Adhesion Molecules / analysis
  • Cell Adhesion Molecules / chemistry*
  • Cells, Cultured
  • Centrifugation, Density Gradient
  • Collagen
  • Cytochalasin D / pharmacology
  • Cytoskeletal Proteins / chemistry
  • Epithelial Cells / chemistry
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism*
  • Extracellular Matrix / drug effects
  • Extracellular Matrix / metabolism
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases
  • Focal Adhesions / metabolism
  • Humans
  • Immunoblotting
  • Immunohistochemistry
  • Kidney Tubules, Collecting / chemistry
  • Kidney Tubules, Collecting / embryology*
  • Kidney Tubules, Collecting / metabolism*
  • Phosphorylation
  • Polycystic Kidney, Autosomal Dominant / genetics
  • Precipitin Tests
  • Protein-Tyrosine Kinases / chemistry
  • Proteins / chemistry
  • Proteins / genetics
  • Proteins / metabolism*
  • TRPP Cation Channels
  • Time Factors
  • Trans-Activators*
  • Tyrosine / chemistry
  • Tyrphostins / pharmacology
  • beta Catenin


  • CTNNB1 protein, human
  • Cadherins
  • Cell Adhesion Molecules
  • Cytoskeletal Proteins
  • Proteins
  • TRPP Cation Channels
  • Trans-Activators
  • Tyrphostins
  • beta Catenin
  • polycystic kidney disease 1 protein
  • Cytochalasin D
  • Tyrosine
  • Collagen
  • Protein-Tyrosine Kinases
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases
  • PTK2 protein, human
  • Calcium