This award supports the PI, Daryl Pring and a graduate student from the University of Florida in a collaboration with Frank Kempken of the Department of General Botany at the Ruhr-University in Bochum, Germany. The goal of the research is to explore cytoplasmic male sterility in sorghum. Prior work by the PI has provided genetic and molecular evidence that defective interactions between the nucleus and the mitochondrion result in pollen abortion. Two fertility restoration genes correct this deleterious interaction-the role of one of those genes is clear, but of the other is not. This research will meld unique genetic and molecular resources to identify the function of the second gene. In more general terms, the project has the potential to demonstrate a unique role of RNA editing in normal reproductive processes, and demonstrate a new pollen-specific regulation of RNA editing.