Figure 16-46. A model for actin filament severing by gelsolin.

Figure 16-46A model for actin filament severing by gelsolin

There are two actin-binding sites in the gelsolin protein. These sites allow gelsolin to bind both along the side and at the end of an actin filament. Filaments that have been severed by gelsolin remain capped at their plus ends. Villin, an actin-bundling protein (see Figure 16-41A), is a member of the same protein family as gelsolin, but it has gained another actin-binding site and lost its ability to sever filaments except at very high (nonphysiological) Ca2+ concentrations.

From: How Cells Regulate Their Cytoskeletal Filaments

Cover of Molecular Biology of the Cell
Molecular Biology of the Cell. 4th edition.
Alberts B, Johnson A, Lewis J, et al.
New York: Garland Science; 2002.
Copyright © 2002, Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter; Copyright © 1983, 1989, 1994, Bruce Alberts, Dennis Bray, Julian Lewis, Martin Raff, Keith Roberts, and James D. Watson .

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