Molecular motors pulling cargos in the viscoelastic cytosol: how power strokes beat subdiffusion
- The discovery of anomalous diffusion of larger biopolymers and submicron tracers such as endogenous granules, organelles, or virus capsids in living cells, attributed to the viscoelastic nature of the cytoplasm, provokes the question whether this complex environment equally impacts the active intracellular transport of submicron cargos by molecular motors such as kinesins: does the passive anomalous diffusion of free cargo always imply its anomalously slow active transport by motors, the mean transport distance along microtubule growing sublinearly rather than linearly in time? Here we analyze this question within the widely used two-state Brownian ratchet model of kinesin motors based on the continuous-state diffusion along microtubules driven by a flashing binding potential, where the cargo particle is elastically attached to the motor. Depending on the cargo size, the loading force, the amplitude of the binding potential, the turnover frequency of the molecular motor enzyme, and the linker stiffness we demonstrate that the motorThe discovery of anomalous diffusion of larger biopolymers and submicron tracers such as endogenous granules, organelles, or virus capsids in living cells, attributed to the viscoelastic nature of the cytoplasm, provokes the question whether this complex environment equally impacts the active intracellular transport of submicron cargos by molecular motors such as kinesins: does the passive anomalous diffusion of free cargo always imply its anomalously slow active transport by motors, the mean transport distance along microtubule growing sublinearly rather than linearly in time? Here we analyze this question within the widely used two-state Brownian ratchet model of kinesin motors based on the continuous-state diffusion along microtubules driven by a flashing binding potential, where the cargo particle is elastically attached to the motor. Depending on the cargo size, the loading force, the amplitude of the binding potential, the turnover frequency of the molecular motor enzyme, and the linker stiffness we demonstrate that the motor transport may turn out either normal or anomalous, as indeed measured experimentally. We show how a highly efficient normal active transport mediated by motors may emerge despite the passive anomalous diffusion of the cargo, and study the intricate effects of the elastic linker. Under different, well specified conditions the microtubule-based motor transport becomes anomalously slow and thus significantly less efficient.…
Verfasserangaben: | Igor A. Goychuk, Vasyl O. Kharchenko, Ralf MetzlerORCiDGND |
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URN: | urn:nbn:de:kobv:517-opus4-76478 |
Titel des übergeordneten Werks (Englisch): | Physical Chemistry Chemical Physics |
Schriftenreihe (Bandnummer): | Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe (181) |
Verlag: | The Royal Society of Chemistry |
Verlagsort: | Cambridge |
Publikationstyp: | Postprint |
Sprache: | Englisch |
Datum der Erstveröffentlichung: | 26.06.2014 |
Erscheinungsjahr: | 2014 |
Veröffentlichende Institution: | Universität Potsdam |
Datum der Freischaltung: | 05.05.2015 |
Freies Schlagwort / Tag: | cambridge cb4 0wf; cambs; england; milton rd; royal soc chemistry; science park; thomas graham house |
Seitenanzahl: | 12 |
Erste Seite: | 16524 |
Letzte Seite: | 16535 |
Quelle: | Phys. Chem. Chem. Phys., 2014,16, 16524-16535. - DOI:10.1039/c4cp01234h |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Peer Review: | Referiert |
Publikationsweg: | Open Access |
Lizenz (Englisch): | Creative Commons - Namensnennung 3.0 Unported |
Externe Anmerkung: | Bibliographieeintrag der Originalveröffentlichung/Quelle |