Abstract:
:Growing knowledge of the key molecular components involved in biological processes such as endocytosis, exocytosis, and motility has enabled direct testing of proposed mechanistic models by reconstitution. However, current techniques for building increasingly complex cellular structures and functions from purified components are limited in their ability to create conditions that emulate the physical and biochemical constraints of real cells. Here we present an integrated method for forming giant unilamellar vesicles with simultaneous control over (i) lipid composition and asymmetry, (ii) oriented membrane protein incorporation, and (iii) internal contents. As an application of this method, we constructed a synthetic system in which membrane proteins were delivered to the outside of giant vesicles, mimicking aspects of exocytosis. Using confocal fluorescence microscopy, we visualized small encapsulated vesicles docking and mixing membrane components with the giant vesicle membrane, resulting in exposure of previously encapsulated membrane proteins to the external environment. This method for creating giant vesicles can be used to test models of biological processes that depend on confined volume and complex membrane composition, and it may be useful in constructing functional systems for therapeutic and biomaterials applications.
journal_name
Proc Natl Acad Sci U S Aauthors
Richmond DL,Schmid EM,Martens S,Stachowiak JC,Liska N,Fletcher DAdoi
10.1073/pnas.1016410108subject
Has Abstractpub_date
2011-06-07 00:00:00pages
9431-6issue
23eissn
0027-8424issn
1091-6490pii
1016410108journal_volume
108pub_type
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