Regulation of actin dynamics by Twinfilin.

Twinfilin is an evolutionarily conserved actin-binding protein initially mischaracterized as a tyrosine kinase but later recognized as a key regulator of cellular actin dynamics. As a member of the ADF-H family, twinfilin binds both actin monomers and filaments. Its role in sequestering G-actin is well-established, but its effects on actin filaments have been debated.

Profilin affects microtubule dynamics via actin.

Profilin binds microtubules in vitro. However, a new study by Vitriol and colleagues (https://doi.org/10.

Multicomponent depolymerization of actin filament pointed ends by cofilin and cyclase-associated protein depends upon filament age.

Intracellular actin networks assemble through the addition of ATP-actin subunits at the growing barbed ends of actin filaments. This is followed by "aging" of the filament via ATP hydrolysis and subsequent phosphate release. Aged ADP-actin subunits thus "treadmill" through the filament before being released back into the cytoplasmic monomer pool as a result of depolymerization at filament pointed ends.

Multicomponent depolymerization of actin filament pointed ends by cofilin and cyclase-associated protein depends upon filament age.

Intracellular actin networks assemble through the addition of ATP-actin subunits at the growing barbed ends of actin filaments. This is followed by "aging" of the filament via ATP hydrolysis and subsequent phosphate release. Aged ADP-actin subunits thus "treadmill" through the filament before being released back into the cytoplasmic monomer pool as a result of depolymerization at filament pointed ends.

Neural-specific alterations in glycosphingolipid biosynthesis and cell signaling associated with two human ganglioside GM3 synthase deficiency variants.

GM3 Synthase Deficiency (GM3SD) is a neurodevelopmental disorder resulting from pathogenic variants in the ST3GAL5 gene, which encodes GM3 synthase, a glycosphingolipid (GSL)-specific sialyltransferase. This enzyme adds a sialic acid to the terminal galactose of lactosylceramide (LacCer) to produce the monosialylated ganglioside GM3. In turn, GM3 is extended by other glycosyltransferases to generate nearly all the complex gangliosides enriched in neural tissue.

Multicomponent regulation of actin barbed end assembly by twinfilin, formin and capping protein.

Cells control actin assembly by regulating reactions at actin filament barbed ends. Formins accelerate elongation, capping protein (CP) arrests growth and twinfilin promotes depolymerization at barbed ends. How these distinct activities get integrated within a shared cytoplasm is unclear.

Multicomponent regulation of actin barbed end assembly by twinfilin, formin and capping protein.

Living cells assemble their actin networks by regulating reactions at the barbed end of actin filaments. Formins accelerate elongation, capping protein (CP) arrests growth and twinfilin promotes depolymerization at barbed ends. How cells integrate these disparate activities within a shared cytoplasm to produce diverse actin networks, each with distinct morphologies and finely tuned assembly kinetics, is unclear.

Pointed-end processive elongation of actin filaments by effectors VopF and VopL.

According to the cellular actin dynamics paradigm, filaments grow at their barbed ends and depolymerize predominantly from their pointed ends to form polar structures and do productive work. We show that actin can elongate at the pointed end when assisted by VopF/L toxins, which act as processive polymerases. In cells, processively moving VopF/L speckles are inhibited by factors blocking the pointed but not barbed ends.

Derivation of Peripheral Nociceptive, Mechanoreceptive, and Proprioceptive Sensory Neurons from the same Culture of Human Pluripotent Stem Cells.

The three peripheral sensory neuron (SN) subtypes, nociceptors, mechanoreceptors, and proprioceptors, localize to dorsal root ganglia and convey sensations such as pain, temperature, pressure, and limb movement/position. Despite previous reports, to date no protocol is available allowing the generation of all three SN subtypes at high efficiency and purity from human pluripotent stem cells (hPSCs). We describe a chemically defined differentiation protocol that generates all three SN subtypes from the same starting population, as well as methods to enrich for each individual subtype.

Laser-induced changes of nonlinear electronic transport properties in LaBaMnO and (LaPr)CaMnO.

We report photoinduced effects in nonlinear third harmonic ac electric transport-which is a measure for the density of correlated polarons-in thin films of [Formula: see text] (LBMO) and [Formula: see text] (LPCMO) manganites. Both materials show an enhancement of third harmonic voltage in the vicinity of the metal-to-insulator transition, indicating strong electron-lattice correlations within a phase-separated state. Relatively low laser excitation with a pulse fluence of [Formula: see text] leads to an increase (decrease) in nonlinearity in LBMO (LPCMO).

Spectral control of elastic dynamics in metallic nano-cavities.

We show how the elastic response of metallic nano-cavities can be tailored by tuning the interplay with an underlying phononic superlattice. In particular, we exploit ultrafast optical excitation in order to address a resonance mode in a tungsten thin film, grown on top of a periodic MgO/ZrO multilayer. Setting up a simple theoretical model, we can explain our findings by the coupling of the resonance in the tungsten to an evanescent surface mode of the superlattice.

Magnetisation switching of FePt nanoparticle recording medium by femtosecond laser pulses.

Manipulation of magnetisation with ultrashort laser pulses is promising for information storage device applications. The dynamics of the magnetisation response depends on the energy transfer from the photons to the spins during the initial laser excitation. A material of special interest for magnetic storage are FePt nanoparticles, for which switching of the magnetisation with optical angular momentum was demonstrated recently.

Magnetization dynamics in magnonic structures with different geometries: interfaces, notches and waveguides.

The discovery of ultrafast magnetization dynamics 20 years ago has led to a broad variety of experimental techniques to explore phenomena in magnetic materials with high temporal resolution. In the current article we present a study dealing with broadband excitation of spin-wave packets at different magnonic crystal continuous magnetic film interfaces. Similar to protected conducting states on the surfaces of topological band insulators, these interfaces exhibit surface spin-wave modes that propagate out of the crystal into the continuous film.

Light-Induced Metastable Magnetic Texture Uncovered by in situ Lorentz Microscopy.

Magnetic topological defects, such as vortices and Skyrmions, can be stabilized as equilibrium structures in nanoscale geometries and by tailored intrinsic magnetic interactions. Here, employing rapid quench conditions, we report the observation of a light-induced metastable magnetic texture, which consists of a dense nanoscale network of vortices and antivortices. Our results demonstrate the emergence of ordering mechanisms in quenched optically driven systems, which may give a general access to novel magnetic structures on nanometer length scales.

Nanomagnonic devices based on the spin-transfer torque.

Magnonics is based on signal transmission and processing by spin waves (or their quanta, called magnons) propagating in a magnetic medium. In the same way as nanoplasmonics makes use of metallic nanostructures to confine and guide optical-frequency plasmon-polaritons, nanomagnonics uses nanoscale magnetic waveguides to control the propagation of spin waves. Recent advances in the physics of nanomagnetism, such as the discovery of spin-transfer torque, have created possibilities for nanomagnonics.

Synchronization of spin Hall nano-oscillators to external microwave signals.

Recently, a novel type of spin-torque nano-oscillators driven by pure spin current generated via the spin Hall effect was demonstrated. Here we report the study of the effects of external microwave signals on these oscillators. Our results show that they can be efficiently synchronized by applying a microwave signal at approximately twice the frequency of the auto-oscillation, which opens additional possibilities for the development of novel spintronic devices.

Magnetic nano-oscillator driven by pure spin current.

With the advent of pure-spin-current sources, spin-based electronic (spintronic) devices no longer require electrical charge transfer, opening new possibilities for both conducting and insulating spintronic systems. Pure spin currents have been used to suppress noise caused by thermal fluctuations in magnetic nanodevices, amplify propagating magnetization waves, and to reduce the dynamic damping in magnetic films. However, generation of coherent auto-oscillations by pure spin currents has not been achieved so far.

Synchronization and chaotic dynamics of coupled mechanical metronomes.

Synchronization scenarios of coupled mechanical metronomes are studied by means of numerical simulations showing the onset of synchronization for two, three, and 100 globally coupled metronomes in terms of Arnol'd tongues in parameter space and a Kuramoto transition as a function of coupling strength. Furthermore, we study the dynamics of metronomes where overturning is possible. In this case hyperchaotic dynamics associated with some diffusion process in configuration space is observed, indicating the potential complexity of metronome dynamics.