Cargo-mooring as an operating principle for molecular motors

JOURNAL OF THEORETICAL BIOLOGY

卷:374

Article

Lisowski, Bartosz^1,2  Kusmierz, Lukasz^1,3  Zabicki, Michal¹  Bier, Martin⁴ 

[1] Jagiellonian Univ, M Smoluchowski Inst Phys, Krakow, Poland

[2] Jagiellonian Univ, Fac Pharm, Unit Pharmacoepidemiol & Pharmacoecon, Coll Med, Krakow, Poland

[3] AGH Univ Sci & Technol, Inst Automat, PL-30059 Krakow, Poland

[4] E Carolina Univ, Dept Phys, Greenville, NC 27858 USA

关键词: Kinesin;    Molecular motors;    Diffusion;    Intracellular transport;   

DOI  :  10.1016/j.jtbi.2015.03.007

来源: Elsevier

【 摘 要 】

Navigating through an ever-changing and unsteady environment, and utilizing chemical energy, molecular motors transport the cell's crucial components, such as organelles and vesicles filled with neurotransmitter. They generate force and pull cargo, as they literally walk along the polymeric tracks, e.g. microtubules. What we suggest in this paper is that the motor protein is not really pulling its load. The load is subject to diffusion and the motor may be doing little else than rectifying the fluctuations, i.e. ratcheting the load's diffusion. Below we present a detailed model to show how such ratcheting can quantitatively account for observed data. The consequence of such a mechanism is the dependence of the transport's speed and efficacy not only on the motor, but also on the cargo (especially its size) and on the environment (i.e. its viscosity and structure). Current experimental works rarely provide this type of information for in vivo studies. We suggest that even small differences between assays can impact the outcome. Our results agree with those obtained in wet laboratories and provide novel insight in a molecular motor's functioning. (C) 2015 Elsevier Ltd. All rights reserved.

【 授权许可】

Free