microtubule

Microtubules are a component of the cytoskeleton. These rope-like polymers of tubulin can grow as long as 25 micrometers and are highly dynamic. The outer diameter of microtubule is about 25 nm.

Microtubules are important for maintaining cell structure, providing platforms for intracellular transport, forming the spindle during mitosis, as well as other cellular processes. There are many proteins that bind to the microtubule, including motor proteins such as kinesin and dynein, severing proteins like katanin, and other proteins important for regulating microtubule dynamics.