Electro-Acoustic Behavior of the Mitotic Spindle: A Semi-Classical Coarse-Grained Model

Abstract

The regulation of chromosome separation during mitosis is not fully understood yet. Microtubules forming mitotic spindles are targets of treatment strategies which are aimed at (i) the triggering of the apoptosis or (ii) the interruption of uncontrolled cell division. Despite these facts, only few physical models relating to the dynamics of mitotic spindles exist up to now. In this paper, we present the first electromechanical model which enables calculation of the electromagnetic field coupled to acoustic vibrations of the mitotic spindle. This electromagnetic field originates from the electrical polarity of microtubules which form the mitotic spindle. The model is based on the approximation of resonantly vibrating microtubules by a network of oscillating electric dipoles. Our computational results predict the existence of a rapidly changing electric field which is generated by either driven or endogenous vibrations of the mitotic spindle. For certain values of parameters, the intensity of the electric field and its gradient reach values which may exert a not-inconsiderable force on chromosomes which are aligned in the spindle midzone. Our model may describe possible mechanisms of the effects of ultra-short electrical and mechanical pulses on dividing cells—a strategy used in novel methods for cancer treatment.

Calcium-independent disruption of microtubule dynamics by nanosecond pulsed electric fields in U87 human glioblastoma cells

“…The resulting microtubule breakage associated with nsPEFs could therefore be caused directly by the force of the applied electric field, disrupting the electrostatic interactions of the microtubules proteins. It has already been proposed by Havelka et al 59. that the electric fields associated with nsPEFs might be sufficient to directly disrupt microtubules and this hypothesis should be tested in future in vitro studies.…”

An Overview of Sub-Cellular Mechanisms Involved in the Action of TTFields

“…AFs and MTs have been implicated in facilitating numerous electrical processes involving ionic and electronic conduction [60,61] and have been theorized to support dipolar and/or ionic kink-like soliton waves traveling at speeds in the 2–100 m/s range [14,62]. Due to strong coupling between electrical and mechanical degrees of freedom in proteins, mechano-electric vibrations of MTs have been modeled both analytically and computationally [63,64]. Electric fields generated by MTs have been modeled extensively and reviewed recently [65,66,67], although experimental measurement of these fields remains extremely difficult, especially in a live cellular environment.…”

Models of Distribution of Electric Field of Primary Cilia as Monopole Antennas

“…Even if the radiated power of the primary cilia is low, it may have an impact on intracellular processes such as the transport of substrates, temporal and spatial organization structures and molecules. It may provide an intracellular and extracellular signaling mechanism [18], may locally change the chemical reaction rates by attracting or rotating the molecular reaction partners [19].…”