Cytoskeleton
The cytoskeleton is a cellular "scaffolding" or "skeleton", used to maintain and/or alter cellular shape.
Composition
The cytoskeleton is composed of actin filaments, microtubules, intermediate filaments, and other proteins.
In addition to holding the cell together, the cytoskeleton is crucial in cell motion, especially amoeba-like movement.
In bacteria
Bacterial cytoskeleton controls cell length and width and the site of cell division.
Organization
Bundles and networks are the most common arrangements of cytoskeletal filaments.
Bundles
In bundles, filaments are packed in parallel arrays.
Networks
In networks, filaments crisscross and are loosely packed.
Membrane microfilaments
Membrane proteins such as cell adhesion proteins can be attached to actin filaments under the cell membrane. Such linkage of adhesion proteins to the cytoskeleton is important for the strong cell adhesion that holds together solid tissues.
Examples
Following are some example cells.
The erythrocyte has the simplest cytoskeleton. It consists of long fibrous spectrin proteins. Ankryin connects the center of spectrin to transmembrane proteins.
