Parameterizing cell movement when the instantaneous cell migration velocity is ill-defined

• DOI: 10.1016/j.physa.2020.124493
• Publication Date: 2020-03-25T23:58:57Z
• Authors: Gilberto L. Thomas; Ismael Fortuna; Gabriel C. Perrone; James A. Glazier; Julio M. Belmonte; Rita M.C. de Almeida
• Keywords: Dimensionless quantity; Constant (computer programming); Langevin equation; Dynamics

Abstract Cell crawling has usually been characterized by a diffusion constant D and instantaneous velocity 〈 | v → | 2 〉 . However, experimentally 〈 | v → | 2 〉 diverges. A three regime (diffusive-ballistic-diffusive) modified Furth equation parameterized by D , the dimensionless excess diffusion coefficient S and the persistence time P is compatible with experiment. S allows comparison of trajectories across experiments and sets limits on the intervals and duration of experiments required to assess cell movement. Cell trajectories in a variety of published experiments are consistent with longitudinal Langevin dynamics and a transverse Wiener process with S ∼ 1 + c o n s t a n t ∗ D − 1 .