Mutations in the dysferlin gene resulting in dysferlin-deficiency lead to limb-girdle muscular dystrophy 2B and Myoshi myopathy in humans. Dysferlin has been proposed as a critical regulator of vesicle-mediated membrane resealing in muscle fibers, and localizes to muscle fiber wounds following sarcolemma damage. Studies in fibroblasts and urchin eggs suggest that trafficking and fusion of intra...

An endocytic vesicle is formed from a flat plasma membrane patch by a sequential process of invagination, bud formation and fission. The scission step requires the formation of a tubular membrane neck (the fission pore) that connects the endocytic vesicle with the plasma membrane. Progress in vesicle fission can be measured by the formation and closure of the fission pore. Live-cell imaging and...

Transport vesicle coat proteins play active roles in vesicle cargo sorting as well as membrane deformation and fission during vesicle biogenesis. For years, it was assumed that this was the extent of the coats' function and that the coats depolymerized immediately after vesicle budding, leaving the exposed fusion machinery free to find, dock, and fuse with the proper target membrane. Recently, ...

After synaptic vesicle fusion, vesicle proteins must be segregated from plasma membrane proteins and recycled to maintain a functional vesicle pool. We monitored the distribution of synaptobrevin, a vesicle protein required for exocytosis, in Caenorhabditis elegans motor neurons by using a pH-sensitive synaptobrevin GFP fusion protein, synaptopHluorin. We estimated that 30% of synaptobrevin was...

A method combined the self-consistent field theory (SCFT) for the rigid rod with the Helfrich curvature elasticity theory for the vesicle has been developed for studying the shape of vesicles anchored by rigid rod. Both the deformation of the vesicle and the density distribution of rod segments can be obtained. Because of the vesicle's impenetrability for the rod segments and the decrease of th...

The cortical actin network is a mesh of filaments distributed beneath the plasmalemma that dynamically reacts in response to stimuli. This dynamic filaments, together with motor myosin partners, adjusts tension, organizes membrane protein microdomains, remodels cell surface and drives vesicle motion order fine-tune exocytosis, endocytosis recycling secretory vesicles. In this review, we discuss...

Because synaptic vesicle exocytosis is a nano-mechanical process, it should be influenced by the mechanical properties of the cell membrane to which the vesicle fuses. By dissolving surfactants at various concentrations in the neuronal membrane, we have perturbed mechanical properties of the membrane and have found that dissolved surfactants lower the probability that a synaptic vesicle will op...

Optically trapped plasmonic nano-heaters are used to mediate efficient and controlled fusion of biological membranes. The fusion method is demonstrated by optically trapping plasmonic nanoparticles located in between vesicle membranes leading to rapid lipid and content mixing. As an interesting application we show how direct control over fusion can be used for studying diffusion of peripheral m...

Physically separating daughter cells during cytokinesis requires contraction of an actin-myosin ring and vesicle-mediated membrane addition at the cleavage furrow. To identify vesicle trafficking proteins that function in cytokinesis, we screened deficiencies and mutations of candidate genes by live imaging the mitotic domains of the Drosophila embryo. In embryos homozygous for some of these de...

A single lipid vesicle can be regarded as an autonomous ultra-miniaturised 3D biomimetic "scaffold" (Ø≥13 nm) ideally suited for reconstitution and interrogation of biochemical processes. The enclosing lipid bilayer membrane of a vesicle can be applied for studying binding (protein/lipid or receptor/ligand interactions) or transmembrane events (membrane permeability or ion channel activation) w...