The research in my lab includes both basic research and practical, or commercial, applications. We try to answer basic questions on the mechanisms of viral assembly and DNA packaging with phi29 nanomotor. The approaches include molecular biology, chemistry, biophysics, computer modeling, and mathematical quantification to investigate fundamental questions such as RNA/protein or RNA/DNA interactions, macromolecular structure and function, nanomotor performance, and energy transformation. We have constructed a functional nanomotor with purified components. We have been able to convert the DNA-filled complexes into infectious virions in the test tube with the exclusive use of proteins from purified or synthetic components. With such a functional synthetic system, we are able to further the study of the mechanisms of the phi29 DNA packaging motor in depth. We then apply the knowledge derived from basic studies to solve practical problems, such as design of nanodevices, applications in nanotechnology, drug/gene/siRNA delivery and therapy of cancer, viral infection and genetic diseases, development of molecular vaccines, diagnosis of diseases, detection of pathogens and single molecule sensing of the environment, single DNA sensing, and design of chips or arrays for computer storage.