title: DNA-mediated self-assembly of artificial vesicles.
abstract: BACKGROUND
  Although multicompartment systems made of single unilamellar vesicles offer the potential to outperform single compartment systems widely used in analytic, synthetic, and medical applications, their use has remained marginal to date. On the one hand, this can be attributed to the binary character of the majority of the current tethering protocols that impedes the implementation of real multicomponent or multifunctional systems. On the other hand, the few tethering protocols theoretically providing multicompartment systems composed of several distinct vesicle populations suffer from the readjustment of the vesicle formation procedure as well as from the loss of specificity of the linking mechanism over time.
  
  
  RESULTS
  In previous studies, we presented implementations of multicompartment systems and resolved the readjustment of the vesicle formation procedure as well as the loss of specificity by using linkers consisting of biotinylated DNA single strands that were anchored to phospholipid-grafted biotinylated PEG tethers via streptavidin as a connector. The systematic analysis presented herein provides evidences for the incorporation of phospholipid-grafted biotinylated PEG tethers to the vesicle membrane during vesicle formation, providing specific anchoring sites for the streptavidin loading of the vesicle membrane. Furthermore, DNA-mediated vesicle-vesicle self-assembly was found to be sequence-dependent and to depend on the presence of monovalent salts.
  
  
  CONCLUSIONS
  This study provides a solid basis for the implementation of multi-vesicle assemblies that may affect at least three distinct domains. (i) Analysis. Starting with a minimal system, the complexity of a bottom-up system is increased gradually facilitating the understanding of the components and their interaction. (ii) Synthesis. Consecutive reactions may be implemented in networks of vesicles that outperform current single compartment bioreactors in versatility and productivity. (iii) Personalized medicine. Transport and targeting of long-lived, pharmacologically inert prodrugs and their conversion to short-lived, active drug molecules directly at the site of action may be accomplished if multi-vesicle assemblies of predefined architecture are used.
authors.affiliation: Artificial Intelligence Laboratory, Department of Informatics, University of Zurich, Zurich, Switzerland. hadorn@ifi.uzh.ch
authors.forename: Maik
authors.initials: M
authors.lastname: Hadorn
authors.forename: Peter
authors.initials: P
authors.lastname: Eggenberger Hotz
mesh_terms: D001665:Binding Sites; D001710:Biotin / Q000737:chemistry; D019921:Biotinylation; D004247:DNA / Q000378:metabolism*; D005452:Fluoresceins / Q000737:chemistry; D008567:Membranes, Artificial; D018613:Microscopy, Confocal / Q000379:methods; D008954:Models, Biological; D010743:Phospholipids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors
chemical_list: D005452:Fluoresceins; D008567:Membranes, Artificial; D010743:Phospholipids; D012492:Salts; C024098:6-carboxyfluorescein; D011092:Polyethylene Glycols; D001710:Biotin; D004247:DNA