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arXiv · 2006.11603

Semiflexible polymer in a gliding assay: reentrant transition, role of turnover and activity

Amir Shee·Nisha Gupta·Abhishek Chaudhuri·Debasish Chaudhuri
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Abstract

We consider a model of an extensible semiflexible filament moving in two dimensions on a motility assay of motor proteins represented explicitly as active harmonic linkers. Their heads bind stochastically to polymer segments within a capture radius, and extend along the filament in a directed fashion before detaching. Both the extension and detachment rates are load-dependent and generate an active drive on the filament. The filament undergoes a first order phase transition from open chain to spiral conformations and shows a reentrant behavior in both the active extension and the turnover, defined as the ratio of attachment-detachment rates. Associated with the phase transition, the size and shape of the polymer changes non-monotonically, and the relevant autocorrelation functions display double-exponential decay. The corresponding correlation times show a maximum signifying the dominance of spirals. The orientational dynamics captures the rotation of spirals, and its correlation time decays with activity as a power law.

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Amir Shee, Nisha Gupta, Abhishek Chaudhuri, Debasish Chaudhuri. 2020-06-20. Semiflexible polymer in a gliding assay: reentrant transition, role of turnover and activity. https://doi.org/10.1039/d0sm01181a

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