Mitotic Spindle Assembly: The Role of Motor Proteins

Abstract The mitotic spindle, a microtubule‐based structure, is required for chromosome segregation during cell division. Motor proteins are molecular machines that utilise the energy of adenosine triphosphate (ATP) hydrolysis to move along microtubules. During cell division, motor proteins are required for spindle formation, chromosome alignment and segregation. Thus, mitotic motor proteins are required for the cell to avoid aneuploidy, a hallmark of cancer. Key Concepts: Molecular motors, including dynein/dynactin and several families of kinesin, are required for mitosis. Kinesins contribute to establishing spindle bipolarity, positioning chromosomes between spindle poles and focusing spindle poles. Dynein contributes to the metaphase checkpoint, spindle positioning, regulating spindle length and pole focusing. To establish and maintain a mitotic spindle, motor proteins achieve a balance of forces on microtubules.