Tug-of-war between opposing molecular motors explains chromosomal oscillation during mitosis

• We model the oscillation of a chromosome observed during mitosis.
• The model probes the role of various molecular motors and dynamics of microtubules.
• A tug-of-war like mechanism between opposite motor species stalls chromosome.
• Duration of a stalled state depends upon the number of kinetochore microtubule.
• Exit from the stall is achieved by stochastically binding the favorable motor species.

Chromosomes move towards and away from the centrosomes during the mitosis. This oscillation is observed when the kinetochore, a specific protein structure on the chromosome is captured by centrosome-nucleated polymer called microtubules. We present a computational model, incorporating activities of various molecular motors and microtubule dynamics, to demonstrate the observed oscillation. The model is robust and is not restricted to any particular cell type. Quantifying the average velocity, amplitude and periodicity of the chromosomal oscillation, we compare numerical results with the available experimental data. Our analysis supports a tug-of-war like mechanism between opposing motors that changes the course of chromosomal oscillation. It turns out that, various modes of oscillation can be fully understood by assembling the dynamics of molecular motors. Near the stall regime, when opposing motors are engaged in a tug-of-war, sufficiently large kinetochore–microtubule generated force may prolong the stall durations.