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Liposomes have been widely employed as membrane scaffolds in the construction of minimal cell models. In 2003, the inverted emulsion method was introduced as a novel technique for generating giant liposomes by transferring water-in-oil droplets across an oil/water interface. This technique enables the encapsulation of purified proteins or cytoplasmic extracts into cell-sized liposomes under physiological buffer conditions, and has since become a cornerstone in bottom-up synthetic biology. Despite its broad application over the past two decades, the effects of lipid composition on the production yield and size distribution of liposomes generated by the inverted emulsion method remain largely unknown.

Allostery is the phenomenon whereby a binding event or covalent modification at one site in a protein modulates function at a distal site thus changing a protein’s functional state. As such, it is a ubiquitous aspect of protein functional regulation. Computationally predicting allosteric states is important as part of the broader challenge of functional annotation, but also has practical implications for drug development, as targeting an allosteric site often affords greater specificity compared with targeting an orthosteric site.

Lipid droplets (LDs) originate from the endoplasmic reticulum (ER), involving lipid exchange between the ER bilayer and the nascent LD monolayer. However, the spontaneous partitioning of lipids based on their chemistry remains unclear. In this study, we use model systems to investigate how saturated and monounsaturated phospholipids partition between the bilayer and the droplet monolayer. Our results demonstrate that lipid saturation influences partitioning, depending on the neutral lipid composition of the droplet.

The kinetics of ion channels arise from transitions through multiple closed and open states. An example is the sigmoidal activation kinetics exhibited by voltage-gated potassium (Kv) channels upon depolarization. This activation sigmoidicity or delay is commonly attributed to the number of closed states that the channel needs to traverse before opening. The Cole-Moore shift refers to the change in this delay upon the magnitude of the hyperpolarization before the activation, and it is empirically obtained by extrapolation of an exponential fit to the time of zero current or by calculating a time shift of the activation kinetics in comparison to a reference trace.

Actin filaments are essential components of the cytoskeleton. Their structural polarity, characterized by distinct 'plus' (barbed) and 'minus' (pointed) ends, is crucial for the directional growth and dynamic behavior of actin filaments during cellular processes such as motility, division, and intracellular transport. Asymmetric and directional filament formation is highly regulated by the bound nucleotide such that ATP-bound G-actin binds on the barbed end, ATP hydrolysis and phosphate dissociation occurs in the filament, and the resulting ADP-bound F-actin dissociates from the pointed end.

Synapsins are the proteins responsible for recruiting synaptic vesicles into the synaptic vesicle cluster. As one of the most abundant synaptic proteins, synapsins are well known to directly interact with the synaptic vesicles, but they can also interact with planar membranes, notably the synaptic membrane, at least indirectly by tethering vesicles to the active zone. In order to contribute to a quantitative understanding of how interactions with synapsin affects the structure of a membrane already prior to neurotransmission, we use a minimal in-vitro model of a lipid monolayer in contact with a subphase containing synapsin 1 and vesicles.

Membraneless organelles (MLOs) are assemblies of biomolecules, which function without a dividing lipid membrane in a cellular environment. These MLOs, termed biomolecular condensates, are commonly formed by the thermodynamic process of liquid-liquid phase separation (LLPS) and assembly of large numbers of proteins, nucleic acids and co-solvent molecules. Within MLOs, certain biomolecule types are particularly causative of phase separation, and are termed “scaffolds” as they provide the major driving forces for self-assembly.

Potassium ion channels are responsible for the rapid selective conduction of K + ions through the cellular membrane. In 1955, Hodgkin and Keynes showed that K + channel conduction occurs via a multi-ion process in which 2-3 ions diffuse in single file along a narrow pore. This process is now commonly referred to as the “knock-on” mechanism. The availability of the crystallographic structure of the KcsA channel at atomic resolution nearly fifty years later made it possible to examine the ion conduction mechanism at the atomic level, prompting multiple molecular dynamics simulation studies.

Biomolecular condensates are membraneless intracellular structures formed from the phase separation of proteins and nucleic acids. Although biomolecular condensates do not have a phospholipid membrane at their surface, recent studies reveal conspicuous assemblies of proteins at the interface between the dense and dilute phases of nucleoli, P granules, and other condensates. The molecular and biophysical rules that govern the surfactant-like localization of these proteins are only beginning to be understood.