Membrane Rafts: Part 2: Looking for Functional Rafts in Cell Membranes (41:55)

In this part, I focus on our laboratory's ongoing preoccupation with rafts where we study the characteristics a... » More

In this part, I focus on our laboratory's ongoing preoccupation with rafts where we study the characteristics a popular "raft-marker", a class of cell surface lipid-tethered proteins, the GPI-anchored proteins. These lipid-tethered molecules are sorted at the cell surface into a specialized endocytic pathway, suggesting their segregation at the cell surface. Here I describe collaborative interdisciplinary work from my laboratory and that of my physicist colleague, Prof. Madan Rao, where we explore the organization of lipid-tethered proteins in living cells using new biophysical tools developed for this purpose. These studies have compelled us to refine the notion of membrane rafts as functional lipid-assemblies consisting of nanoscale clusters and monomers. This organization appears to be characteristic of many other putative "raft" lipids and lipid-anchored proteins at the inner and outer leaflet of cell membranes. « Hide