Cell surface design

Abstract

CONSIDERATIONS of membrane fluidity (see refs 1–5) have often involved schematic representations of the cell plasma membrane and underlying cytoskeletal structures^3–5. But, although intended to show how microtubules, microfilaments and so on might interfere with the mobility of membrane components, such models have not been drawn to scale. Usually microtubules and microfilaments seem much smaller than the plasma membrane, whereas the reverse is true. Thus, it has not been possible to evaluate fully the relative importance of plasma membrane and cytoskeleton in influencing cell surface dynamics. I have therefore tried to draw these various elements to scale. Since the data come from heterogeneous sources (fibroblasts, muscle cells, amoeba, plant cells, epithelial cells and lymphocytes) it is clear that the organisation of the various structures represented here can only be hypothetical and does not correspond to a known structure in a given cell type.