DICAM, a novel dual immunoglobulin domain containing cell adhesion molecule interacts with alphavbeta3 integrin

J Cell Physiol. 2008 Sep;216(3):603-14. doi: 10.1002/jcp.21438.

Abstract

Immunoglobulin (Ig) superfamily members are abundant with diverse functions including cell adhesion in various tissues. Here, we identified and characterized a novel adhesion molecule that belongs to the CTX protein family and named as DICAM (Dual Ig domain containing cell adhesion molecule). DICAM is a type I transmembrane protein with two V-type Ig domains in the extracellular region and a short cytoplasmic tail of 442 amino acids. DICAM is found to be expressed ubiquitously in various organs and cell lines. Subcellular localization of DICAM was observed in the cell-cell contact region and nucleus of cultured epithelial cells. Cell-cell contact region was colocalized with tight junction protein, ZO-1. The DICAM increased MDCK cell adhesion to 60% levels of fibronectin. DICAM mediated cell adhesion was specific for the alphavbeta3 integrin; other integrins, alpha2, alpha5, beta1, alpha2beta1, alpha5beta1, were not involved in cell adhesion. In identifying the interacting domain of DICAM with alphavbeta3, the Ig domain 2 showed higher cell adhesion activity than that of Ig domain 1. Although RGD motif in Ig domain 2 was engaged in cell adhesion, it was not participated in DICAM-alphavbeta3 mediated cell adhesion. Furthermore, differentially expressing DICAM stable cells showed well correlated cell to cell adhesion capability with integrin beta3-overexpressing cells. Collectively, these results indicate that DICAM, a novel dual Ig domain containing adhesion molecule, mediates cell adhesion via alphavbeta3 integrin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Adhesion / physiology*
  • Cell Adhesion Molecules / classification
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism*
  • Cell Line
  • Humans
  • Immunoglobulins / metabolism
  • Integrin alphaVbeta3 / genetics
  • Integrin alphaVbeta3 / metabolism*
  • Membrane Proteins / classification
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Molecular Sequence Data
  • Phylogeny
  • Protein Structure, Tertiary
  • Sequence Alignment
  • Tissue Distribution

Substances

  • Cell Adhesion Molecules
  • DICAM protein, mouse
  • Immunoglobulins
  • Integrin alphaVbeta3
  • Membrane Proteins