Techniques for studying lipid rafts

Lipid Rafts. Edited by T.J. McIntosh. 2007. Methods in Molecular Biology. Volume 398, Humana Press, Totowa, New Jersey, USA. 326 pp., $99.50. ISBN 978 1 58829 729 7.

Lipid rafts have been defined recently [1], [2] as ‘small (10–200 nm), heterogeneous, highly dynamic, sterol- and sphingolipid-enriched domains that compartmentalize cellular processes. Small rafts can sometimes be stabilized to form larger platforms through protein-protein and protein-lipid interactions’. These membrane microdomains have been implicated in the compartmentalization of a range of cellular processes, including intracellular trafficking, transmembrane signalling, lipid and protein sorting, viral uptake and regulated proteolysis.

This latest addition to the Humana Press ‘Methods in Molecular Biology’ series provides detailed methods on a range of techniques that are currently in use to detect, isolate and characterize rafts and components in them in both artificial bilayers and biological membranes. Following a brief introductory chapter that provides an overview of membrane rafts, there is a chapter by Deborah Brown on the commonly used detergent-based method to isolate rafts and a chapter describing non-detergent based methods, including immunoisolation using anti-caveolin antibodies. There then follows a series of chapters describing both emerging and more established biophysical techniques to detect and characterize rafts in a range of membrane systems, both monolayers and bilayers, including giant unilamellar vesicles (GUVs), supported lipid bilayers and native membrane sheets. These techniques include fluorescence-quenching, fluorescence microscopy, fluorescence correlation microscopy, multiphoton laser-scanning microscopy, spatial analysis of dehydroergosterol distributions, NMR, EPR discrimination by oxygen transport, plasmon-waveguide resonance spectroscopy, fluorescence recovery after photobleaching, single-molecule tracking, X-ray diffraction, small-angle neutron scattering, electron microscopy and atomic force microscopy. The final two chapters describe atomistic and coarse-grained computer simulations of raft-like lipid mixtures and a microscopic model calculation of the phase diagram of ternary mixtures of cholesterol and saturated and unsaturated phospholipids.

The chapters follow the standard style for books in this series, providing easy to follow protocols accompanied by helpful notes. The variety and range of contributions from numerous experts in the raft field will make this an extremely useful book for both for those just setting out on a voyage of raft discovery, as well as those already immersed in this exciting, and often controversial, field. Nigel M. Hooper Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK [email protected]