Simulation to clarify the role of microtubules in cell growth

Abstract

Plant materials sometimes have high mechanical strength in its outer structure which is derived from the cell wall at the microscopic level. Since the deposition of the cell wall is thought to be induced by the microtubule alignment inside cells, it is important to know the microtubule dynamics from the viewpoints of both plant and materials sciences. To investigate the microtubule dynamics in silico, we constructed an agent-based model of microtubule that simulates the growth and shrinkage of microtubules with microtubule-microtubule interactions. In addition to this initial setup, we further considered the condition of the edge-catastrophe that microtubule is to shrink when it hits the edge of the geometry, or the condition of the tension-catastrophe that cell surface tension induces the shrinkage. By introducing these conditions to our model, we aim to elucidate how the ring-like microtubules are formed during plant zygote development. Our formulation suggests a control parameter of the orientation order from the collective behavior of microtubules. It would greatly help to test some hypotheses on the microtubule ring formation that have been experimentally difficult to investigate.