Phase separation of lipid membranes analyzed with high-resolution secondary ion mass spectrometry.
Lateral variations in membrane composition are postulated to play a central role in many cellular events, but it has been difficult to probe membrane composition and organization on length scales of tens to hundreds of nanometers. We present a high-resolution imaging secondary ion mass spectrometry technique to reveal the lipid distribution within a phase-separated membrane with a lateral resolution of approximately 100 nanometers. Quantitative information about the chemical composition within small lipid domains was obtained with the use of isotopic labels to identify each molecular species. Composition variations were detected within some domains.
Kraft
Mary L
ML
Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
Weber
Peter K
PK
Longo
Marjorie L
ML
Hutcheon
Ian D
ID
Boxer
Steven G
SG
D002462:Cell Membrane / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008563:Membrane Lipids / Q000032:analysis*; D021962:Membrane Microdomains / Q000737:chemistry* / Q000648:ultrastructure; D008565:Membrane Proteins / Q000032:analysis; D036103:Nanotechnology; D010713:Phosphatidylcholines / Q000032:analysis*; D018629:Spectrometry, Mass, Secondary Ion / Q000379:methods*
D008051:Lipid Bilayers; D008563:Membrane Lipids; D008565:Membrane Proteins; D010713:Phosphatidylcholines; C015153:1,2-dilauroylphosphatidylcholine; C010942:1,2-distearoyllecithin