Integrated membrane protein analysis of mature and embryonic stem cell-derived smooth muscle cells using a novel combination of CyDye/biotin labeling

Mol Cell Proteomics. 2007 Oct;6(10):1788-97. doi: 10.1074/mcp.M600433-MCP200. Epub 2007 Jul 11.

Abstract

Cultivated vascular smooth muscle cells (SMCs) were surface-labeled with CyDyes followed by biotinylation. After enrichment on avidin columns, proteins were separated on large format gradient gels by SDS-PAGE. A comparison between CyDye-tagged and non-tagged gel bands revealed a substantial increase of protein identifications from membrane, membrane-associated, and extracellular matrix proteins with a corresponding reduction in co-purified intracellular proteins. Notably the majority of identified proteins were involved in cellular adhesion processes. To demonstrate the quantitative potential of this platform, we performed a comparison between mature and embryonic stem cell-derived smooth muscle cells (esSMCs) and identified the membrane proteins E-cadherin, integrin alpha6, and CD98 (4F2) to be significantly up-regulated in esSMCs suggesting that SMCs derived from embryonic stem cells maintain characteristics of their embryonic stem cell origin. This was subsequently confirmed by RT-PCR: despite expressing a panel of smooth muscle markers (calponin, Sm22, and aortic smooth muscle actin), esSMCs remained positive for markers of stem cell pluripotency (Oct4, Nanog, and Rex1). In summary, we describe a novel strategy for the profiling of cell membrane proteins. The procedure combines DIGE technology with biotin/avidin labeling to discriminate membrane and membrane-associated proteins from intracellular contaminants by fluorescence tagging and permits semiquantitative differential expression analysis of membrane proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Biotin / metabolism*
  • Coloring Agents / metabolism*
  • Electrophoresis, Gel, Two-Dimensional
  • Electrophoresis, Polyacrylamide Gel
  • Embryonic Stem Cells / chemistry*
  • Embryonic Stem Cells / cytology
  • Mass Spectrometry
  • Membrane Proteins / analysis*
  • Membrane Proteins / chemistry
  • Membrane Proteins / isolation & purification
  • Mice
  • Mice, Inbred C57BL
  • Microscopy, Confocal
  • Molecular Sequence Data
  • Myocytes, Smooth Muscle / chemistry*
  • Myocytes, Smooth Muscle / cytology*
  • Peptides / chemistry
  • Peptides / metabolism
  • Receptors, Cell Surface / chemistry
  • Receptors, Cell Surface / metabolism
  • Staining and Labeling / methods*

Substances

  • Coloring Agents
  • Membrane Proteins
  • Peptides
  • Receptors, Cell Surface
  • Biotin