Helical motors and formins synergize to compact chiral filopodial bundles: A theoretical perspective.
Eur J Cell Biol
; 103(1): 151383, 2024 Mar.
Article
in En
| MEDLINE
| ID: mdl-38237507
ABSTRACT
Chiral actin bundles have been shown to play an important role in cell dynamics, but our understanding of the molecular mechanisms which combine to generate chirality remains incomplete. To address this, we numerically simulate a crosslinked filopodial bundle under the actions of helical myosin motors and/or formins and examine the collective buckling and twisting of the actin bundle. We first show that a number of proposed mechanisms to buckle polymerizing actin bundles without motor activity fail under biologically-realistic parameters. We then demonstrate that a simplified model of myosin spinning action at the bundle base effectively "braids" the bundle, but cannot control compaction at the fiber tips. Finally, we show that formin-mediated polymerization and motor activity can act synergitically to compact filopodium bundles, as motor activity bends filaments into shapes that activate twist forces induced by formins. Stochastic fluctuations of actin polymerization rates and slower cross linking dynamics both increase buckling and decrease compaction. We discuss implications of our findings for mechanisms of cytoskeletal chirality.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Actin Cytoskeleton
/
Actins
Type of study:
Prognostic_studies
Language:
En
Journal:
Eur J Cell Biol
/
Eur. j. cell biol
/
European journal of cell biology
Year:
2024
Document type:
Article
Affiliation country:
Estados Unidos
Country of publication:
Alemania