Research in our laboratory is multidisciplinary with efforts directed at understanding virus biology and its role in disease as well as studies aimed at engineering viruses and other biological components for application in nano-based systems and devices. We utilize a multitude of approaches in our studies and collaborate with scientists in fields ranging from structural biology to microfabrication. Our goal is to utilize discoveries in virus biology to develop new approaches for their control and use.

Virus Host Interactions:
Viruses cause significant reductions in food, fiber and forage throughout the world. Yet despite their importance we still understand relatively little of the disease processes through which viruses function to reduce crop productivity. Our biological studies focus on understanding how viruses cause disease or induce resistance responses. To examine these interactions we utilize Tobacco mosaic virus (TMV) as an important pathogen model. Current studies are directed at understanding the structure and function of the viral replicase and its multifunctional role in virus biology and host responses. Specifically, we are interested in how the replicase protein localizes and is portioned within the cell, how the replicase complex assemblies and what host factors are involved in these processes. Understanding these essential virus processes should provide insight into the mechanisms essential for virus replication and movement.

Another focus area addresses the identification of signaling pathways involved in disease development. These studies utilize genomic approaches, such as cDNA microarrays, to identify host genes and pathways that are disrupted during the infection process. We then seek to link disrupted genes or pathways to specific disease responses as well as to specific virus-host interactions or functions. Our long-term goal is to utilize this information in the development of plants that are incapable of supporting virus replication and/or disease development.

Selected References:
Culver, JN, Padmanabhan, MS. (2007). Virus-induced disease: alterin host physiology one interaction at a time. Annu. Rev. Phytopathol. In Press.

Padmanabhan MS, Shiferaw H, Culver, JN (2006). The Tobacco mosaic virus replicase protein disrupts the localization and function of interacting Aux/IAA proteins. Mol. Plant-Microbe Interact.19:864-873.

Padmanabhan, M.S., Goregaoker, S.P., Golem, S., Shiferaw, H., and Culver, J.N. (2005). Interaction of the Tobacco mosaic virus replicase protein with the Aux/IAA proteins PAP1/IAA26 is associated with disease development. J. Virology, 79:2549-2558.

Golem, S. and Culver J.N. 2003. Tobacco mosaic virus induced alterations in the gene expression profile of Arabidopsis thaliana. Mol. Plant-Microbe Interact. 16:681-688.

Goregaoker, S.P. and Culver, J.N. 2003. Oligomerization and activity of the helicase domain of the tobacco mosaic virus 126/183-kDa replicase proteins. J. Virology 77:3549-3556.

Virus Based Nanotechnology:
Advances in nanotechnology offer significant improvements in a range of applications including, light weight materials with greater strength, increased energy efficiency from electronic devices, and better sensors for a range of environmental and manufacturing uses. Furthermore, since size constraints often produce qualitative changes in the characteristics of matter, it is anticipated that the exploitation of nanotechnology will result in the identification of new phenomena and functionalities derived from the physics, chemistry, and biology of matter at the nanoscale level. However, these advances will require the development of systems for the design, modeling, and synthesis of nanoscale materials. Interestingly, many biological molecules function on this scale and possess unique properties that impart the ability to assume defined conformations and assemblies, as well as interact with specific chemical or biological substrates. Specific studies in our laboratory utilize simple RNA plant viruses as templates for the self-assembly and patterning of novel nanomaterials. We are interested in developing methodologies to produce assembled arrays of functionalized viruses for use in sensors, energy harvesting and drug delivery. We combine both genetic and chemical approaches to address our bioengineering efforts with the long-term aim of integrating renewable biological components into the manufacture of nanoscale materials and devices.

Selected References:
Yi H, Rubloff, GW, Culver, JN. (2007) TMV Microarrays: Hybridization-based assembly of DNA-programmed viral nanotemplates. Langmuir, 23:2663-2667.

Royston E, Lee SY, Culver JN, Harris MT. (2006) Characterization of silica-coated Tobacco mosaic virus. J Colloid Interface Sci.298:705-712.

Lee SY, Choi J, Royston EJ, Culver JN, Harris MT. (2006). Deposition of Platinum Clusters on the Surface Modified Tobacco Mosaic Virus. J. Nanoscience and Nanotechnology. 27:4165-4168.

Yi H, Nisar S, Lee SY, Powers MA, Bentley WE, Payne GF, Ghodssi R, Rubloff GW, Harris MT, Culver JN. (2005)

Patterned assembly of genetically modified viral nanotemplates via nucleic acid hybridization. Nano Lett. 5(10):1931-6.
Dujardin, E., Peet, C., Stubbs, G., Culver, J.N., and Mann, S. 2003. Organization of metallic nanoparticles using tobacco mosaic virus templates. NanoLetters, 3, 413-417.