NER: Oligonucleotide-Directed Alignment of Cytoskeletal Filaments for Nanoscale Assembly

NER: Oligonucleotide-directed alignment of cytoskeletal

filaments for nanoscale assembly

There is currently great interest in nanoscience and nanotechnology for manipulating material at submicron scales. In cells, however, this is a routine task -- the transport of intracellular cargo is carried out by motor proteins that move along cytoskeletal filaments called microtubules. Directional movement is achieved because microtubules have a structural polarity and motors move unidirectionally along them, with different motors moving in different directions. We seek to: (i) reconstruct the intracellular transport system in vitro using purified kinesin motor proteins and microtubules, and (ii) use it to transport defined cargo (biological or synthetic nanoscale objects) to specific sites on a two-dimensional substrate. To lay down microtubule tracks with desired orientations, we will take advantage of the specificity and reversibility of DNA hybridization as a 'molecular glue'. Single-stranded DNA oligonucleotides will be attached to defined sites on glass surfaces and complementary oligonucleotides will be covalently attached to microtubules. By making microtubules whose ends are functionalized with different DNA sequences and spatially patterning their sequence complements, a variety of microtubule geometries will be investigated. These tracks will be used to direct the motion of cargo-laden kinesin motors as a step towards building systems for biomolecular separations or directed assembly applications.