Mitotic spindle is mainly composed of which protein?

Spindle fibres are composed of a large number of microtubules which is made up of a single layer of globulin protein. These microtubules are made by polymerisation of globular tubulin proteins. Related Theory The two centrosomes give rise to the mitotic spindle which regulates the movement of chromosomes during mitosis. At the centre of each animal cell, the centrosomes of animal cells are associated with a pair of rod-like objects, the centrioles, which are at right angles to each other.