Abstract HIV can infect non-dividing cells because the viral capsid overcome selective barrier of nuclear pore complex and deliver genome directly into nucleus 1,2 . Remarkably, intact is more than 1,000 times larger size limit prescribed by diffusion 3 This in central channel composed intrinsically disordered nucleoporin domains enriched phenylalanine–glycine (FG) dipeptides. Through multivalent FG interactions, cellular karyopherins their bound cargoes solubilize this phase to drive...

Morphodynamic equations governing the behaviour of active nematic fluids on deformable curved surfaces are constructed in large deformation limit. Emphasis is placed formulation objective rates that account for normal deformations whilst ensuring tangential flows Eulerian, and use surface derivative (rather than covariant derivative) free energy, which elastically couples local order to out-of-plane bending surface. Focusing geometry its dynamical interplay with hydrodynamics, several...

We propose and analyze an active hydrodynamic theory that characterizes the effects of scaffold protein anillin. Anillin is found at major sites cortical activity, such as adherens junctions cytokinetic furrow, where canonical regulator actomyosin remodeling small GTPase, RhoA. RhoA acts via intermediary ``effectors'' to increase both rates activation myosin motors polymerization actin filaments. has been shown this action RhoA---improving critical in signaling pathway without altering...

The cytoskeletal component actomyosin is a canonical example of active matter since the power-stroke cycle locally converts chemical energy in form adenoside triphosphate (ATP) into mechanical work for remodeling. Observing myosin II minifilaments as they remodel actin , we now report that at high concentrations ATP, metastable swirling patterns are characterized by recurrent vortex and spiral-like motifs, whereas low such structures give way to asterlike patterns. To explain this, construct...

Morphodynamic descriptions of fluid deformable surfaces are relevant for a range biological and soft matter phenomena, spanning materials that can be passive or active, as well ordered topological. However, principled, geometric formulation the correct hydrodynamic equations has remained opaque, with objective rates proving central, contentious issue. We argue this is due to conflation several important notions must disambiguated when describing surfaces. These Eulerian Lagrangian...

Living systems are chiral on multiple scales, from constituent biopolymers to large scale morphology, and their active mechanics is both driven by components serves generate morphologies. We describe the of fluid membranes in coordinate-free form, with focus contributions stress. These geometric ``odd elastic'' forces response mean curvature gradients but directed perpendicularly. As a result, they induce tangential membrane flows that circulate around maxima minima curvature. When normal...

Motivated by the mechanics of dynamin-mediated membrane tube fission we analyse stability fluid tubes subjected to shear flow in azimuthal direction. We find a novel helical instability driven which results non-equilibrium steady state for fluctuations. This has its onset at rates that may be physiologically accessible under action dynamin and could also probed using in-vitro experiments on nanotubes, e.g. magnetic tweezers. discuss how such an play role mechanism fission.

We study a membrane tube with unidirectional ion pumps driving an osmotic pressure difference. A pressure-driven peristaltic instability is identified, qualitatively distinct from similar tension-driven Rayleigh-type instabilities on tubes. discuss how this could be related to the function and biogenesis of bound organelles, in particular, contractile vacuole complex. The unusually long natural wavelength agreement that observed cells.

Summary Paragraph HIV can infect non-dividing cells because the viral capsid overcome selective barrier of nuclear pore complex and deliver genome directly into nucleus. Remarkably, intact is over one thousand times greater than size-limit prescribed by pore’s diffusion barrier. This a phase-separated condensate in central channel comprised intrinsically-disordered nucleoporin domains enriched phenylalanine-glycine (FG) dipeptides. Through multivalent FG-interactions, cellular karyopherins...

Membrane tubes are essential structural features in cells that facilitate biomaterial transport and inter- intracellular signaling. The shape of these can be regulated by the proteins surround adhere to them. We study stability a biomembrane tube coated with combining linear analysis, out-of-equilibrium hydrodynamic calculations, numerical solutions Helfrich-like membrane model. Our analysis demonstrates both long- short-wavelength perturbations destabilize tubes. Numerical simulations...

The Gaussian (saddle splay) rigidity of fluid membranes controls their equilibrium topology but is notoriously difficult to measure. In lipid mixtures, typical living cells, linear interfaces separate liquid ordered (LO) from disordered (LD) bilayer phases at subcritical temperatures. Here we consider such supported by curved supports that thereby control the membrane curvatures. We show how spectral analysis fluctuations LO-LD interface provides a novel way measuring difference in between...

Utilising Onsager's variational formulation, we derive dynamical equations for the relaxation of a fluid membrane tube in limit small deformation, allowing contrast solvent viscosity across and variations surface tension due to incompressibility. We compute rates, recovering known results case purely axis-symmetric perturbations making new predictions higher order (azimuthal) $m$-modes. analyse long short wavelength limits these modes by use various asymptotic arguments. incorporate...

We propose and analyse an active hydrodynamic theory that characterises the effects of scaffold protein anillin. Anillin is found at major sites cortical activity, such as adherens junctions cytokinetic furrow, where canonical regulator actomyosin remodelling small GTPase, RhoA. RhoA acts via intermediary 'effectors' to increase both rates activation myosin motors polymerisation actin filaments. has been shown this action - improving critical in signalling pathway without altering essential...

Morphodynamic descriptions of fluid deformable surfaces are relevant for a range biological and soft matter phenomena, spanning materials that can be passive or active, as well ordered topological. However, principled, geometric formulation the correct hydrodynamic equations has remained opaque, with objective rates proving central, contentious issue. We argue this is due to conflation several important notions must disambiguated when describing surfaces. These Eulerian Lagrangian...

Membrane tubes are essential structural features in cells that facilitate biomaterial transport and inter- intracellular signalling. The shape of these can be regulated by the proteins surround adhere to them. We study stability a biomembrane tube coated with combining linear analysis, out-of-equilibrium hydrodynamic calculations, numerical solutions Helfrich-like membrane model. Our analysis demonstrates both long short-wavelength perturbations destabilise tubes. Numerical simulations...

The cytoskeletal component actomyosin is a canonical example of active matter since the powerstroke cycle locally converts chemical energy in form adenoside triphosphate (ATP) into mechanical work for remodelling. Observing myosin II minifilaments as they remodel actin {\it vitro}, we now report that, at high concentrations ATP, meta-stable swirling patterns that are characterised by recurrent vortex- and spiral-like motifs, whereas low such structures give way to aster-like patterns. This...

Living systems are chiral on multiple scales, from constituent biopolymers to large scale morphology, and their active mechanics is both driven by components serves generate morphologies. We describe the of fluid membranes in coordinate-free form, with focus contributions stress. These geometric `odd elastic' forces response mean curvature gradients but directed perpendicularly. As a result, they induce tangential membrane flows that circulate around maxima minima curvature. When normal...

Morphodynamic equations governing the behaviour of active nematic fluids on deformable curved surfaces are constructed in large deformation limit. Emphasis is placed formulation objective rates that account for normal deformations whilst ensuring tangential flows Eulerian, and use surface derivative (rather than covariant derivative) free energy, which elastically couples local order to out-of-plane bending surface. Focusing geometry its dynamical interplay with hydrodynamics, several...