The endocytosis process is of critical importance for a variety of cellular life functions. Vesicle formation during receptor-mediated endocytosis involves a complex protein machinery and additional proteins to control it. Although our understanding of this endocytic machinery has grown rapidly during the last decade, little is known about how it interconnects functionally with the cortical cytoskeleton underlying the plasma membrane.
In lower eukaryotes such as yeast, genetic analysis connects the actin cytoskeleton to endocytosis. In mammalian cells, the link is not so convincing. Introducing actin-perturbing drugs (reviewed in Geli and Riezman 1998) or mutant forms of the Rho family of small GTPases (reviewed in Ellis and Mellor 2000) disrupts endocytosis in some cells types with some assays, but not in all cases (Gottlieb et al. 1993; Jackman et al. 1994; Lamaze et al. 1997...
