October 4, 2012 @ 5:00 pm – 6:00 pm
Humanities Wing, University of Toronto Scarborough,Toronto,ON M1C 1A4, Canada
“Three-Dimensional DNA Structures for Biological and Material Applications”
Professor Hanadi Sleiman, McGill University, Montreal, QC
Three-dimensional structures made of DNA hold the potential to encapsulate and release drugs, selectively encage nanomaterials, regulate the activity of proteins,and assemble networks for catalysis and biomolecule crystallization. A number of strategies for DNA construction have been developed, through weaving together DNA strands into tiles, or stapling a DNA strand into origami structures. Our group has been examining a different approach to build DNA nanostructures, in which synthetic molecules are used to control and modify DNA self-assembly.
We will describe the use of this approach to generate 3D-DNA structures, such as DNA cages and nanotubes, with deliberate variation of geometry, size, single- and double-stranded forms, permeability and length. These can be dynamically switched to different internal volumes, and can be ‘opened’ or closed with specific DNA strands. The size-selective encapsulation of gold nanoparticles within these host structures and the release of this cargo when specific DNA strands are added will be shown. Moreover, these compact 3D-DNA structures can travel across the plasma membrane of a number of mammalian cells, without the aid of transfection reagents. The molecules shown here represent a new class of selective cellular probes and drug delivery tools, and can assist the development of nucleic acid therapeutic routes. Finally, the use of these cages for the site-specific 3D-organization of synthetic polymer chains in their core or corona will be described.
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