The time correlation functions of the thermal undulations of a lipid membrane have been studied by molecular dynamics simulations of a coarse-grained bilayer model. We observe a double-exponential decay, with relaxation rates in good agreement with the theory by Seifert and Langer, [Europhys. Lett. 23, 71 (1993)]. Intermonolayer friction resulting from local velocity differences between the two...

Dysregulation of lipid metabolism in individual tissues leads to systemic disruption of insulin action and glucose metabolism. Utilizing quantitative lipidomic analyses and mice deficient in adipose tissue lipid chaperones aP2 and mal1, we explored how metabolic alterations in adipose tissue are linked to whole-body metabolism through lipid signals. A robust increase in de novo lipogenesis rend...

New methods toward manipulation and study of membrane species within a lipid bilayer platform are desired because lipid bilayers are able to maintain native conformation and function of intrinsic membrane species. This report demonstrates design and use of a bilayer patterned device for separation, sorting, and categorization of membrane biomolecules based on their affinity for different co-exi...

The aquaporin-1 water channel was modeled in a palmitoyl-oleoyl-phosphatidyl-choline lipid bilayer, by means of molecular dynamics simulations. Interaction of the protein with the membrane and inter-monomer interactions were analyzed. Structural features of the channel important for its biological function, including the Asn-Pro-Ala (NPA) motifs, and the diffusion of water molecules into the ch...

The cubic mesophase formed by monoacylglycerols and water is an important medium for the in meso crystallogenesis of membrane proteins. To investigate molecular level lipid and additive interactions within the cubic phase, a method was developed for improving the resolution of (1)H NMR spectra when using a conventional solution state NMR probe. Using this approach we obtained well-resolved J-co...

An experimental model for cytoplasmic organization is presented. We demonstrate dynamic control over protein distribution within synthetic cells comprising a lipid bilayer membrane surrounding an aqueous polymer solution. This polymer solution generally exists as two immiscible aqueous phases. Protein partitioning between these phases leads to microcompartmentation, or heterogeneous protein dis...

The surface expansion that is induced by the lateral pressure in the brush region of lipid membranes containing grafted polymers is deduced from the scaling and mean-field theories for the polymer brush, together with the equation of state for a lipid monolayer at the equivalence pressure with fluid lipid bilayers. Depending on the length and mole fraction of the polymer lipid, the membrane exp...

Lipids and proteins are organized in cellular membranes in clusters, often called 'lipid rafts'. Although raft-constituent ordered lipid domains are thought to be energetically unfavourable for membrane fusion, rafts have long been implicated in many biological fusion processes. For the case of HIV gp41-mediated membrane fusion, this apparent contradiction can be resolved by recognizing that th...

The perturbations induced in a lipid bilayer by the presence of a transmembrane nanotube are investigated using coarse grained molecular dynamics. Meniscus formation by the lipids and tilting of the nanotube occur in response to hydrophobic mismatch, although these two effects do not compensate completely for the total mismatch. The lipid head-to-tail vector field is examined and shows strong o...

It is important that we understand the mechanism of the penetration of particles into a living cell to achieve advances in bionanotechnology, such as for treatment, visualization within a cell, and genetic modification. Although there have been many studies on the application of functional particles to cells, the basic mechanism of penetration across a biological membrane is still poorly unders...