Publications

Abstract not provided.

Abstract not provided.

Active transport systems provide essential functions in terms of cell physiology and metastasis. These systems, however, are also co-opted by invading viruses, enabling directed transport of the virus to and from the cell's nucleus (i.e., the site of virus replication). Based on this concept, fundamentally new approaches for interrogating and manipulating the inner workings of living cells may be achievable by co-opting Nature's active transport systems as an in vivo biomolecular tool. The overall goal of this project was to investigate the ability to engineer kinesin-based transport systems for in vivo applications, specifically the collection of effector proteins (e.g., transcriptional regulators) within single cells. In the first part of this project, a chimeric fusion protein consisting of kinesin and a single chain variable fragment (scFv) of an antibody was successfully produced through a recombinant expression system. The kinesin-scFv retained both catalytic and antigenic functionality, enabling selective capture and transport of target antigens. The incorporation of a rabbit IgG-specific scFv into the kinesin established a generalized system for functionalizing kinesin with a wide range of target-selective antibodies raised in rabbits. The second objective was to develop methods of isolating the intact microtubule network from live cells as a platform for evaluating kinesin-based transport within the cytoskeletal architecture of a cell. Successful isolation of intact microtubule networks from two distinct cell types was demonstrated using glutaraldehyde and methanol fixation methods. This work provides a platform for inferring the ability of kinesin-scFv to function in vivo, and may also serve as a three-dimensional scaffold for evaluating and exploiting kinesin-based transport for nanotechnological applications. Overall, the technology developed in this project represents a first-step in engineering active transport system for in vivo applications. Further development could potentially enable selective capture of intracellular antigens, targeted delivery of therapeutic agents, or disruption of the transport systems and consequently the infection and pathogenesis cycle of biothreat agents.

The technique of active capture and transport of virus particles using a biomolecular motor-driven, nanoscale antibody sandwich assay was described. Nanofluidic transport of macromolecules within living cells is achieved using a complex, three-dimensional network of cytoskeletal filaments and motor proteins. It is observed that glutaraldehyde crosslinking successfully linked fluorescent antibodies to MT shuttles. The application of kinesin and Ab-MT as mechanical actuators enables the development of nanofluidic systems that rely only on chemical energy for capturing and separating of target analytes from a complex solution.

Abstract not provided.