Isolation of desmosomes from the epidermis of Xenopus laevis and immunochemical characterization of the Xenopus desmosomal cadherins

Cell Struct Funct. 2004 Feb;29(1):17-26. doi: 10.1247/csf.29.17.

Abstract

Here we report a new method of isolating epidermal desmosomes from Xenopus laevis, and a major constituent of desmosomes designated as Xenopus desmogleins (XDsg). Isolation of desmosomes from Xenopus laevis epidermis was carried out by a two step-incubation with different concentrations of NP-40. After discontinuous sucrose gradient centrifugation at 30,000 g for 60 min, a pure desmosomal fraction was obtained at 30%/40% interface. In the SDS-PAGE of isolated desmosomes, at least 12 bands (XDB1 to XDB12) were observed over a 75 kD region. Among them, three bands (XDB3, XDB7, XDB8; estimated MW 175, 124, and 112 kD respectively) were recognized as glycoproteins based on ConA binding. Monospecific polyclonal antibody against XDB3 cross-reacted with bovine Dsgs and vis-a-vis anti-bovine Dsgs with XDB3. By contrast, monospecific antibody against bovine Dsc a/b did not cross-react with either XDB7 or XDB8. Heterogeneous molecular constituents of desmosomal adhesion molecule, which have been observed among different bovine tissues, were confirmed in a phylogenetically different animal, Xenopus laevis. Combined results with other evidence could suggest an alternative system for desmosome-mediated cell adhesion.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Cadherins / analysis*
  • Cattle
  • Desmosomes / chemistry*
  • Desmosomes / ultrastructure
  • Electrophoresis, Polyacrylamide Gel
  • Epidermis / chemistry*
  • Glycoproteins / analysis
  • Immunohistochemistry*
  • Male
  • Microscopy, Electron
  • Xenopus laevis

Substances

  • Cadherins
  • Glycoproteins