During vesicular trafficking and release of enveloped viruses, the budding and fission processes dynamically remodel the donor cell membrane in a protein- or a lipid-mediated manner. In all cases, in addition to the generation or relief of the curvature stress, the buds recruit specific lipids and proteins from the donor membrane through restricted diffusion for the development of a ring-type raft domain of closed topology. Here, by reconstituting the bud topography in a model membrane, we demonstrate the preferential localization of cholesterol- and sphingomyelin-enriched microdomains in the collar band of the bud-neck interfaced with the donor membrane. The geometrical approach to the recapitulation of the dynamic membrane reorganization, resulting from the local radii of curvatures from nanometre-to-micrometre scales, offers important clues for understanding the active roles of the bud topography in the sorting and migration machinery of key signalling proteins involved in membrane budding.

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During vesicle budding or endocytosis, biomembranes undergo a series of lipid- and protein-mediated deformations involving cholesterol-enriched lipid rafts. If lipid rafts of high bending rigidities become confined to the incipient curved membrane topology such as a bud-neck interface, they can be expected to reform as ring-shaped rafts. Here, we report on the observation of a disk-to-ring shape morpho-chemical transition of a model membrane in the absence of geometric constraints. The raft shape transition is triggered by lateral compositional heterogeneity and is accompanied by membrane deformation in the vertical direction, which is detected by height-sensitive fluorescence interference contrast microscopy. Our results suggest that a flat membrane can become curved simply by dynamic changes in local chemical composition and shape transformation of cholesterol-rich domains.

Printing solid-state elastic conductors into self-supporting three-dimensional (3D) geometries promises the design diversity of soft electronics, enabling complex, multifunctional, and tailored human-machine interfaces. However, the di culties in manipulating their rheological characteristics have only allowed for layerwise deposition. Here, we report omnidirectional printing of elastic conductors enabled by emulsifying elastomer composites with immiscible, nonvolatile solvents. The strategy simultaneously achieves superior viscoelastic properties that provide the structural integrity of printed features, and pseudoplastic and lubrication behaviours that allow great printing stability. Freestanding, lamentary, and out-of-plane 3D geometries of intrinsically stretchable conductors are directly written, achieving a minimum feature size <100 μm and excellent stretchability >150%. Particularly, the evaporation of the continuous phase in the emulsion results in microstructured, surface-localized conductive networks, signi cantly improving their electrical conductivity. To illustrate the feasibility of our approach, we demonstrate skin-mountable electronics that visualize temperature on a matrix-type stretchable display based on omnidirectionally printed elastic interconnects. Full TextSkin electronics augment the capability of shareable signals from personal and metabolic activities over communication networks by blurring the physical discontinuity between electronic devices and human skin [1][2][3][4] . With their unique mechanical characteristics, such as lightweight design, softness, and stretchability, skin electronics can be functionalized on various body parts 5,6 and even brains 7 and hearts 8 in the forms of biosensors, processors, and displays. For high-delity operation under these challenging circumstances, the design of skin electronics needs to be tailored elaborately to individuals 9,10 . However, traditional mask-based lithography primarily optimized for the mass production of standardized, uniform electronics cannot effectively deal with the morphological diversity of the human bodies. Moreover, existing manufacturing processes still lack strategies to implement threedimensional (3D) structures with soft functional materials such as vertical interconnect accesses (VIAs) and multilayer circuitries that are crucial to the realization of high-performance, multifunctional applications.Printing electrical wirings into 3D structures could be a promising solution for maximizing the customizability of skin electronics and achieving circuit complexity. However, most conventional 3D printing processes still deposit one layer at a time, which is unsuitable for complex, lamentary, and omnidirectional wirings (including a z-directional component). Alternatively, viscoelastic inks that simultaneously exhibit high quasi-static stiffness and strong shear-thinning behaviour can immediately solidify after extrusion from a nozzle-based printhead, allowing direct writing of self-supporting 3D structures [11][12][13][14][15...