Physics of Actin Filaments

Bending Rigidity of Actin

Fluctuations of a semi-flexible actin filament confined to a quasi 2D chamber. The methods developed to extract the bending rigidity are described  by Brangwyne et al. Biophys. J. 93 (2007),  346-359.

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Confined actin filaments

Actin Rings and Their Supercoiling Transition

When confined to 2D surface, actin rings will spontaneously anneal end-to-end  and form ring like structures. Furthermore rings labeled with rhodamine phalloidin will spontaneously supercoil, a process that can be directly visualize with video microscopy. This phenomena has been described by Sanchez et. al. PRL 104 (2010) 098103.

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Supercoiling of actin rings

Actin Racquets

In the presence of attractive interactions semi-flexible actin filaments collapse into ring or racquet like structures. Analysis of the resulting racquets yields a new method of measuring the strength of the attractive potential between a pair of filaments. This work has been described by Lau et al. EPL 87 (2009) 48006.

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Actin filament racquets