• Physics 16, s113
Simulations present that the topology of biopolymer “tangles” controls how organic cells resist deformation.
Skinny baggage stuffed with water aren’t the apparent materials for constructing sturdy, advanced constructions. However in relation to developing organic tissues, such baggage—which organic cells basically resemble—are what nature has to work with. To offer the mandatory mechanical properties, cells’ interiors are bolstered with numerous biopolymer networks, with every community resisting pressure in a special stress regime. Now Marco Pensalfini of the Polytechnic College of Catalonia, Spain, and his colleagues have investigated the dynamics of certainly one of these networks—the so-called intermediate-filament (IF) community—which helps hold the cells in epithelial tissues intact below massive deformations . The researchers present that the function of this community as a mobile “security web” depends upon how the filaments tangle collectively.
IFs are versatile, extensible strands of protein just a few micrometers in size. Reverse ends of those strands connect to movable spots on a cell’s membrane. When relaxed, the filaments are coiled, forming a diffuse tangle all through the cell’s quantity. Below pressure, the filaments are pulled taut, such that they kind a star-shaped community that has a dense knot at its heart. This reconfiguration limits additional deformation.
Pensalfini and his colleagues simulated IF networks in polygonal cells whose sides had been pulled outward. They assorted the topology of the networks—the diploma to which the filaments wrapped round one another—and measured the way it affected the purpose at which the filaments turned taut. They discovered that they may use a easy topological measure impartial of the community’s dimension to foretell the pressure required to “activate” the filaments and interact the security web. Subsequent, the researchers intend to review how IF networks work together with the opposite biopolymer networks current in cells.
Marric Stephens is a Corresponding Editor for Physics Journal based mostly in Bristol, UK.
- M. Pensalfini et al., “Nonaffine mechanics of entangled networks impressed by intermediate filaments,” Phys. Rev. Lett. 131, 058101 (2023).