Intellectual Merit. RNA viruses are among the most challenging infectious agents. Some RNA viruses cause serious diseases in human beings, while other RNA viruses do so to livestock or to crop plants. One of the main problems limiting the control of RNA viruses is rapid change of their genetic information which leads to constant emergence of new viral strains. RNA recombination involves the exchange of viral RNA fragments and the strategies of RNA recombination are key tools needed for RNA viruses to secure their fast adaptation and evolution. In contrast to genetic recombination of DNA-based organisms including DNA viruses, RNA recombination in RNA viruses is not well studied. The Brome mosaic virus (BMV) system is an excellent well-elaborated model for the understanding of basic mechanisms of RNA recombination. In this project the research will focus on the characterization of the molecular factors that are responsible for efficient homologous BMV RNA-RNA crossovers. The project takes advantage of a previously localized region on the BMV RNA molecule that supports unusually high frequency of recombination (defined as the RNA3 intercistronic recombination hot-spot or "sgp") as well as a recently discovered novel subgenomic (sg) BMV RNA (named as "sgRNA3a") in order to elucidate which of the known multiple functions of the sgp is responsible for recombination. The experimental design of this project relies on testing of the modified BMV RNA3 constructs in a variety of both in vitro and in vivo assays. The intellectual merit of the project lies in its investigation of the roles of sgRNA molecules in a model RNA virus system. These studies will provide the scientists with new information about molecular strategies that are utilized by RNA viruses to condition the efficient genetic recombination. Results from these studies will contribute to a more integrated picture of recombination mechanisms that will be applicable to other RNA viruses.
Broader impacts of the project. This project will contribute significantly to our knowledge about viral molecular adaptations, and will help to draw analogies between DNA and RNA genetics, by using the BMV model system. BMV is a member of a larger RNA virus super-family, and its molecular strategies are common among other viruses. This research will provide students with hands-on training in the important areas of biochemistry, molecular biology, plant biology, and virology. The principal investigator teaches a molecular virology course and this work will train young virologists. Also, the principal investigator teaches an advanced course entitled "The RNA World". The principal investigator has a long record of undergraduate training including those from underrepresented groups. All the students will be encouraged to present their research at scientific meetings (e.g., Sigma Xi, American Society of Plant Biologists, American Society for Virology). The principal investigator's group maintains collaborations with the University of Chicago and with an Institute of Bioorganic Chemistry in Poznan, Poland, and keeps active contacts with several international virology groups. These interactions will enhance the exposure of the students to the international environment. The principal investigator is making efforts to disseminate science by translation of English works (has translated into Polish language a book by Matt Ridley "Red Queen, sex and evolution of human nature"). In general, social benefits of this project rely upon improvement of our understanding of RNA recombination in RNA viruses which will provide new potential means for control of these important infectious agents. It will also raise the scientific literacy of the public via outreach activities. By learning how to predict recombination hot-spots scientists will be able to design more stable viral vectors as important biotechnology tools.
