In situ chemical cross-linking on living cells reveals CD9P-1 cis-oligomer at cell surface

J Proteomics. 2009 Nov 2;73(1):93-102. doi: 10.1016/j.jprot.2009.08.005. Epub 2009 Aug 22.

Abstract

Tetraspanins are integral membrane proteins involved in a variety of physiological and pathological processes. They associate with each other in multimolecular complexes containing numerous membrane proteins. As a first step towards the study of the supramolecular organization of tetraspanin complexes, we have implemented a proteomic approach based on in situ protein cross-linking on living cells followed by affinity purification of tetraspanin complexes. This allowed observing the presence of high molecular weight protein complexes that were characterized as containing CD9P-1/CD315 using LC-MS/MS. Western blot analyses and the use of different tags demonstrated the presence of CD9P-1 oligomer in cis-association at cell surface. A significant amount of CD9P-1 oligomer was observed on various cell types. We have shown that CD9P-1 self-associates independently from its association with tetraspanins. However, the expression level of CD9 or CD81 that associate directly and specifically with CD9P-1, positively modulates the cross-linking efficiency of CD9P-1. Thus, tetraspanins can play a role on CD9P-1 oligomerization status.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antigens, CD / metabolism
  • Antigens, Surface / chemistry
  • Antigens, Surface / metabolism
  • Cell Membrane / drug effects*
  • Cell Membrane / metabolism
  • Cells, Cultured / drug effects*
  • Cross-Linking Reagents / pharmacology*
  • Humans
  • Isomerism
  • K562 Cells
  • Membrane Glycoproteins / metabolism
  • Membrane Proteins / metabolism
  • Models, Biological
  • Multiprotein Complexes / metabolism
  • Neoplasm Proteins / chemistry
  • Neoplasm Proteins / metabolism*
  • Protein Binding
  • Protein Interaction Mapping
  • Protein Multimerization / drug effects
  • Tetraspanin 28
  • Tetraspanin 29
  • Tetraspanins

Substances

  • Antigens, CD
  • Antigens, Surface
  • CD81 protein, human
  • CD9 protein, human
  • Cross-Linking Reagents
  • Membrane Glycoproteins
  • Membrane Proteins
  • Multiprotein Complexes
  • Neoplasm Proteins
  • PTGFRN protein, human
  • TSPAN1 protein, human
  • Tetraspanin 28
  • Tetraspanin 29
  • Tetraspanins