Characterization of PINCH-2, a new focal adhesion protein that regulates the PINCH-1-ILK interaction, cell spreading, and migration

J Biol Chem. 2002 Oct 11;277(41):38328-38. doi: 10.1074/jbc.M205576200. Epub 2002 Aug 6.

Abstract

Integrin-linked kinase (ILK) is a multidomain protein that plays important roles at cell-extracellular matrix (ECM) adhesion sites. We describe here a new LIM-domain containing protein (termed as PINCH-2) that forms a complex with ILK. PINCH-2 is co-expressed with PINCH-1 (previously known as PINCH), another member of the PINCH protein family, in a variety of human cells. Immunofluorescent staining of cells with PINCH-2-specific antibodies show that PINCH-2 localizes to both cell-ECM contact sites and the nucleus. Deletion of the first LIM (LIM1) domain of PINCH-2 abolished the ability of PINCH-2 to form a complex with ILK. The ILK-binding defective LIM1-deletion mutant, unlike the wild type PINCH-2 or the ILK-binding competent LIM5-deletion mutant, was incapable of localizing to cell-ECM contact sites, suggesting that ILK binding is required for this process. Importantly, the PINCH-2-ILK and PINCH-1-ILK interactions are mutually exclusive. Overexpression of PINCH-2 significantly inhibited the PINCH-1-ILK interaction and reduced cell spreading and migration. These results identify a novel nuclear and focal adhesion protein that associates with ILK and reveals an important role of PINCH-2 in the regulation of the PINCH-1-ILK interaction, cell shape change, and migration.

Publication types

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

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Animals
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Adhesion / physiology
  • Cell Line
  • Cell Movement / physiology*
  • Cell Size
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Extracellular Matrix / metabolism
  • Focal Adhesions / chemistry*
  • Focal Adhesions / metabolism
  • Genes, Reporter
  • Humans
  • Immunohistochemistry
  • LIM Domain Proteins
  • Membrane Proteins
  • Mice
  • Molecular Sequence Data
  • Nuclear Proteins / metabolism
  • Protein Serine-Threonine Kinases / metabolism*
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism

Substances

  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • DNA-Binding Proteins
  • LIM Domain Proteins
  • LIMS1 protein, human
  • LIMS2 protein, human
  • Lims1 protein, mouse
  • Lims2 protein, mouse
  • Membrane Proteins
  • Nuclear Proteins
  • Recombinant Fusion Proteins
  • integrin-linked kinase
  • Protein Serine-Threonine Kinases

Associated data

  • GENBANK/AF484961