Cytoskeleton

The eukaryotic cytoskeleton. Actin filaments are shown in red, microtubules in green, and the nuclei are in blue.

Cytoskeleton is the skeleton of the cell, constructed from proteins. They lie on cytoplasm, defining cell's shape, movement and many other functions. There are 3 types of them which we will discuss shortly.

Actin filaments

Actin cytoskeleton of mouse embryo fibroblasts, stained with Fluorescein isothiocyanate-phalloidin

Actin filaments are strings anchored one end in the plasma membrane. They generates contractile forces, which helps the cell moves and changes shape.

Actin filaments are also called microfilaments because they are the thinnest in cytoskeleton family.