A semiflexible polymer in a gliding assay: reentrant transition, role of turnover and activity. Issue 8 (13th January 2021)

• Record Type: Journal Article
• Authors: Shee, Amir; Gupta, Nisha; Chaudhuri, Abhishek; Chaudhuri, Debasish
• Is Part Of: Soft matter. Volume 17:Issue 8(2021)
• Page Start: 2120
• Page End: 2131
• Publication Date: 2021-01-13
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/d0sm01181a
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : An extensible semiflexible filament moving on a motility assay of motor proteins undergoes first order re-entrant phase transition from open chain to spiral as a function of the extension rate and turnover of motor proteins. 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 the open chain to spiral conformation 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 change non-monotonically, and the relevant autocorrelation functions display a 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.