Heterotypic trans-interaction of LI- and E-cadherin and their localization in plasmalemmal microdomains

J Mol Biol. 2008 Apr 18;378(1):44-54. doi: 10.1016/j.jmb.2008.02.023. Epub 2008 Feb 20.

Abstract

Cadherins are calcium-dependent adhesion molecules important for tissue morphogenesis and integrity. LI-cadherin and E-cadherin are the two prominent cadherins in intestinal epithelial cells. Whereas LI-cadherin belongs to the subfamily of 7D (seven-domain)-cadherins defined by their seven extracellular cadherin repeats and short intracellular domain, E-cadherin is the prototype of classical cadherins with five extracellular domains and a highly conserved cytoplasmic part that interacts with catenins and thereby modulates the organization of the cytoskeleton. Here, we report a specific heterotypic trans-interaction of LI- with E-cadherin, two cadherins of distinct subfamilies. Using atomic force microscopy and laser tweezer experiments, the trans-interaction of LI- and E-cadherin was characterized on the single-molecule level and on the cellular level, respectively. This heterotypic interaction showed similar binding strength (20-52 pN at 200-4000 nm/s) and lifetime (0.8 s) as the respective homotypic interactions of LI- and E-cadherin. VE-cadherin, another classical cadherin, did not bind to LI-cadherin. In enterocytes, LI-cadherin and E-cadherin are located in different membrane regions. LI-cadherin is distributed along the basolateral membrane, whereas the majority of E-cadherin is concentrated in adherens junctions. This difference in membrane distribution was also reflected in Chinese hamster ovary cells stably expressing either LI- or E-cadherin. We found that LI-cadherin is localized almost exclusively in cholesterol-rich fractions, whereas E-cadherin is excluded from these membrane fractions. Given their different membrane localization in enterocytes, the heterotypic trans-interaction of LI- and E-cadherin might play a role during development of the intestinal epithelium when the cells do not yet have elaborate membrane specializations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Cadherins / analysis
  • Cadherins / metabolism*
  • Cricetinae
  • Cricetulus
  • Humans
  • Membrane Microdomains / chemistry
  • Membrane Microdomains / metabolism*
  • Mice
  • Microscopy, Atomic Force

Substances

  • CDH17 protein, human
  • Cadherins