Molecular motors transporting cargos in viscoelastic cytosol: how to beat subdiffusion with a power stroke?

Abstract

Anomalously slow passive diffusion, $⟨\delta x^2(t)⟩\simeq t^{\alpha }$, with $0<\alpha <1$, of larger tracers such as messenger RNA and endogenous submicron granules in the cytoplasm of living biological cells has been demonstrated in a number of experiments and has been attributed to the viscoelastic physical nature of the cellular cytoplasm. This finding provokes the question to which extent active intracellular transport is affected by this viscoelastic environment: does the subdiffusion of free submicron cargo such as vesicles and organelles always imply anomalously slow transport by molecular motors such as kinesins, that is, directed transport characterized by a sublinear growth of the mean distance, $⟨x(t)⟩\simeq t^{{\alpha }_{\mathrm{eff}}}$, with $0<{\alpha }_{\mathrm{eff}}<1$? Here we study a generic model approach combining the commonly accepted two-state Brownian ratchet model of kinesin motors based on the continuous-state diffusion along microtubule driven by a flashing binding potential. The motor is elastically coupled to a cargo particle, which in turn is subject to the viscoelastic cytoplasmic environment. Depending on the physical parameters of cargo size, loading force, amplitude of the binding potential, and the turnover frequency of the molecular motor, the transport can be both normal (${\alpha }_{\mathrm{eff}}=1$) and anomalous ($\alpha \le {\alpha }_{\mathrm{eff}}<1$). In particular, we demonstrate in detail how highly efficient normal motor transport can emerge despite the anomalously slow passive diffusion of cargo particles, and how the active motion of the same motor in the same cell may turn anomalously slow when the parameters are changed.

References in corpus (4)

• Anomalous transport in the crowded world of biological cells
• Coexistence and efficiency of normal and anomalous transport by molecular motors in living cells
• Subdiffusive rocking ratchets in viscoelastic media: transport optimization and thermodynamic efficiency in overdamped regime
• Rocking Subdiffusive Ratchets: Origin, Optimization and Efficiency

Cited by in corpus (22)

• Anomalous, non-Gaussian tracer diffusion in heterogeneously crowded environments
• Non-universal tracer diffusion in crowded media of non-inert obstacles
• Facilitation of polymer looping and giant polymer diffusivity in crowded solutions of active particles
• On subdiffusive continuous time random walks with stochastic resetting
• Superstatistical generalised Langevin equation: non-Gaussian viscoelastic anomalous diffusion
• Ageing underdamped scaled Brownian motion: ensemble and time averaged particle displacements, non-ergodicity, and the failure of the overdamping approximation
• Viscoelastic subdiffusion in a random Gaussian environment
• Anomalous transport of subdiffusing cargos by single kinesin motors: the role of mechanochemical coupling and anharmonicity of tether
• Molecular machines operating on nanoscale: from classical to quantum
• Non-Markovian intracellular transport with sub-diffusion and run-length dependent detachment rate
• Universal singularities of anomalous diffusion in the Richardson class
• Modeling magnetosensitive ion channels in viscoelastic environment of living cells
• Active transport improves the precision of linear long distance molecular signalling
• Anomalous diffusion, non-Gaussianity, and nonergodicity for subordinated fractional Brownian motion with a drift
• On the motion of kinesin in a viscoelastic medium
• Carnot, Stirling, Ericsson stochastic heat engines: Efficiency at maximum power
• Conservative random walks in confining potentials
• Active and Passive Transport of Cargo in a Corrugated Channel: A Lattice Model Study
• Inertia-driven propulsion of asymmetric spinner-dimers at moderate Reynolds numbers
• Hyperphosphorylation-Induced Phase Transition in Vesicle Delivery Dynamics of Motor Proteins in Neuronal Cells
• Investigation of multiple-dynein transport of melanosomes by non-invasive force measurement using fluctuation unit $\chi$
• Langevin equation and fractional dynamics