Skip to Main content Skip to Navigation
Journal articles

Geometrical Constraints Greatly Hinder Formin mDia1 Activity

Abstract : Formins are one of the central players in the assembly of most actin networks in cells. The sensitivity of these processive molecular machines to mechanical tension is now well established. However, how the activity of formins is affected by geometrical constraints related to network architecture, such as filament crosslinking and formin spatial confinement, remains largely unknown. Combining microfluidics and micropatterning, w e reconstituted in vitro mDia1 formin-elongated filament bundles induced by fascin, with different geometrical constraints on the formins, and measured the impact of these constraints on formin elongation rates and processivity. When filaments are not bundled, formins can be anchored to static or fluid surfaces, by either end of the proteins, without affecting their activity. We show that filament bundling by fascin reduces both unanchored formin elongation rate and processivity. Strikingly, when filaments elongated by surface-anchored formins are cross-linked together, formin elongation rate immediately decreases and processivity is reduced, up to 24-fold, depending on the cumulative impact of formin rotational and translational freedoms. Our results reveal an unexpected crosstalk between the constraints at the filament and the formin levels. We anticipate that in cells, the molecular details of formin anchoring to the plasma membrane, strongly modulate formin activity at actin filament barbed ends.
Document type :
Journal articles
Complete list of metadatas
Contributor : Guillaume Romet-Lemonne <>
Submitted on : Monday, December 28, 2020 - 12:17:37 PM
Last modification on : Thursday, January 7, 2021 - 3:38:14 AM


Files produced by the author(s)




Emiko Suzuki, Jahnavi Chikireddy, Serge Dmitrieff, Bérengère Guichard, Guillaume Romet-Lemonne, et al.. Geometrical Constraints Greatly Hinder Formin mDia1 Activity. Nano Letters, American Chemical Society, 2020, 20 (1), pp.22-32. ⟨10.1021/acs.nanolett.9b02241⟩. ⟨hal-03087738⟩



Record views


Files downloads