Iron (Fe) is an essential mineral for plants, and the humans and animals that consume plants. Iron deficiency hinders crop production on neutral-to-alkaline soils, which occur on approximately 30% of the earth. One of the most important unanswered questions in the plant Fe nutrition field is, "How do plants sense and respond to Fe status?" Iron deficient Arabidopsis thaliana and other plant species accumulate additional copper (Cu) in leaves. The investigators hypothesize that this Cu accumulation is a specific Fe deficiency response that allows the plant to use Cu containing proteins in place of Fe containing proteins. The investigators will use a genetic mapping approach to identify key components that carry out or control this Cu uptake activity. Additionally, the investigators hypothesize that specific molecules called microRNAs are key mediators in the plant's ability to switch from Fe containing proteins to Cu containing proteins. This will be tested by measuring gene expression data in wild-type and certain mutant plants. It is anticipated that certain genes that encode Cu containing proteins are regulated directly by plant Fe status. The major long-term goal of this research is to understand mechanisms of plant Fe accumulation in optimal and adverse environments. In a broader sense, this information could be used to develop crop varieties with increased Fe concentrations in edible portions or varieties that are more productive under low Fe conditions. This project will provide training activities for one postdoctoral scientist, one graduate student, one undergraduate student, and one high school student in the Young Nebraska Scientist program. Additionally, educational videos or plants science lessons will be produced and made available to the public on the Plant and Soil Sciences eLibrary (http://plantandsoil.unl.edu).