title: Extracting the stepping dynamics of molecular motors in living cells from trajectories of single particles.
abstract: Molecular motors are responsible of transporting a wide variety of cargos in the cytoplasm. Current efforts are oriented to characterize the biophysical properties of motors in cells with the aim of elucidating the mechanisms of these nanomachines in the complex cellular environment. In this study, we present an algorithm designed to extract motor step sizes and dwell times between steps from trajectories of motors or cargoes driven by motors in cells. The algorithm is based on finding patterns in the trajectory compatible with the behavior expected for a motor step, i.e., a region of confined motion followed by a jump in the position to another region of confined motion with similar characteristics to the previous one. We show that this algorithm allows the analysis of 2D trajectories even if they present complex motion patterns such as active transport interspersed with diffusion and does not require the assumption of a given step size or dwell period. The confidence on the step detection can be easily obtained and allows the evaluation of the confidence of the dwell and step size distributions. To illustrate the possible applications of this algorithm, we analyzed trajectories of myosin-V driven organelles in living cells.
authors: Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 1, Ciudad Universitaria, CP 1428 Ciudad de Buenos Aires, Argentina.
authors: Augusto
authors: A
authors: Bruno
authors: Luciana
authors: L
authors: Bruno
authors: Valeria
authors: V
authors: Levi
mesh_terms: D000465:Algorithms; D000818:Animals; D001692:Biological Transport; D002470:Cell Survival; D019295:Computational Biology / Q000379:methods*; D007700:Kinetics; D020460:Melanosomes / Q000378:metabolism; D009068:Movement; D024701:Myosin Type V / Q000378:metabolism*; D029867:Xenopus Proteins / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D029867:Xenopus Proteins; D024701:Myosin Type V