Preparation of cell membranes for high resolution imaging by AFM

Ultramicroscopy. 2010 Mar;110(4):305-12. doi: 10.1016/j.ultramic.2009.12.014. Epub 2010 Jan 4.

Abstract

Studies of cell membrane structure by atomic force microscopy (AFM) have been limited because of the softness of cell membranes. Here, we utilize a new technique of sample preparation to lay red blood cell membranes on the top of a mica surface to obtain high resolution images by in-situ AFM on both sides of cell membranes. Our results indicate that the location of oligosaccharides and proteins in red blood cell membranes might be different from the current membrane model. The inner membrane leaflet is covered by dense proteins with fewer free lipids than expected. In contrast, the outer membrane leaflet is quite smooth; oligosaccharides and peptides supposed to protrude out of the outer membrane leaflet surface might be actually hidden in the middle of hydrophilic lipid heads; transmembrane proteins might form domains in the membranes revealed by PNGase F and trypsin digestion. Our result could be significant to interpret some functions about red blood cell membranes and guide to heal the blood diseases related to cell membranes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Membrane / metabolism
  • Cell Membrane / ultrastructure*
  • Cytological Techniques
  • Erythrocyte Membrane / ultrastructure
  • Humans
  • Image Processing, Computer-Assisted
  • Microscopy, Atomic Force / methods*