DYNAMICS OF MICROTUBULE MOLECULAR MOTORS IN LIVING CELLS

MARCELO SALIERNO; LUCIANA BRUNO; MARCELO DESPOSITO; VALERIA LEVI

Buzios, RJ, Brasil

Congreso; VII Iberoamerican Congress of Biophysics; 2009

DYNAMICS OF MICROTUBULE MOLECULAR MOTORS IN LIVING CELLS. Marcelo Salierno, Luciana Bruno, Marcelo A. Desposito, Valeria Levi. Departamento de Física, FCEyN, UBA, Buenos Aires, Argentina. Abstract: The cytoplasm organization depends on molecular motors that distribute organelles and other cellular cargoes along microtubules and actin filaments to their correct destination. The biophysical properties of molecular motors have been extensively analyzed in in vitro assays however, the in vivo behavior of motors cannot be extrapolated from their in vitro properties. In order to understand the molecular mechanisms that regulate motor-driven transport in vivo, we studied the transport of pigment organelles along microtubules in Xenopus laevis melanophores by using single particle tracking. We analyzed the organelles trajectories using a novel theoretical model which considers the different forces involved in the transport. By fitting the model to the experimental data, we could quantify biophysical properties of the motors cytoplasmic dynein and kinesin-2 and get insight the influence of the intracellular environment on the transport.