Research
overview:
|
 presenting at SIAM LS22 |
| A
size-dependent transition from steady
contraction to contractile waves and spirals
in actomyosin networks with turnover We first collaborated with Prof. Kinneret Keren’s lab at Technion, who study the periodic contractile dynamics of actomyosin networks immersed in water-in-oil droplets. Alex and I designed a theoretical model of the actomyosin network as a viscous fluid with viscosity and contractile parameters that are determined by whether the network is percolated, allowing the coexistence of different local density-dependent mechanical states. Through analysis and simulation, we showed how simple changes in system geometry, particularly system size, can generate varied contractile patterns (Krishna et al. 2022, “Size-dependent transition from steady contraction to waves in actomyosin networks with turnover,” bioRxiv). Friction patterns guide actin network contraction in reconstituted actomyosin networks Most recently, Alex and I collaborated with the Cytomorpho Lab of Profs. Laurent Blanchoin and Manuel Théry to demonstrate the critical role of friction in patterning actomyosin network contraction (Colin et al. 2022, “Friction patterns guide actin network contraction,” bioRxiv). In the lab, they observe that reconstituted actomyosin networks on micropatterned surfaces self-organize such that myosin, condensed in a few spots, rapidly compacts the whole actin network. The compaction point is the center of homogeneous domains and biased to more adhesive regions of heterogeneous patterns. Experiments indicate the contraction pattern is largely insensitive to the randomized myosin distribution. We modeled the actomyosin network as a 2D deformable viscoelastic cable-network material with active contractile stresses generated by myosin spots advected by the deforming network. Analysis and simulation illuminated the reason why the adhesion, not myosin, pattern determines the compaction point. In summer '23, I traveled to the Cytomorpho Lab in Paris, France to get some hands-on practical biology lab experience; this fantastic visit gave me insight into the experimental perspective on a variety of biomechanical problems in cellular biology. Current/in progress work: Currently, Alex and I are interested in understanding the dynamics of contractile stress fibers under tension. This project is in its preliminary stages |
