M.L. Guerinot and E.L. Connolly Metal Uptake in Arabidopsis thaliana 1/7/04
Iron is an essential nutrient and the ability to accumulate iron from the diet is crucial for human health. Currently, more people suffer from malnutrition due to micronutrient deficiencies than from deficiencies of protein or energy and it is estimated that over 2 billion people worldwide suffer from iron deficiency. In agriculture, the availability of iron in soil plays a major part in determining crop yields. In addition, plants are the main dietary source of iron for much of the world's population. However, iron can also be toxic to both plants and animals when present at high levels. Thus, all cells must carefully regulate iron uptake. The long-range goal of these studies is to understand how plants take up iron from the soil and how plants maintain proper iron levels in the various cells/tissues of the plant. Previously, the FRO2 gene was identified as a critical component of the iron uptake system in Arabidopsis thaliana; FRO2 encodes a low iron inducible ferric chelate reductase responsible for reduction of iron at the root surface. The current studies are aimed at further characterization of FRO2 as well as three additional FRO family members (FRO3, FRO6 and FRO7). Specifically, the roles of each FRO in iron uptake and homeostasis will be examined using a variety of molecular, cellular and biochemical approaches. A second aim focuses on a transcription factor (bHLH29) and its role in controlling FRO gene expression in an iron-dependent fashion. The proposed studies will ultimately lead to a better understanding of iron uptake in plants and to the design of plants that are capable of growth on iron deficient soils and that accumulate iron and thus have a higher nutritional value.
This collaborative project will provide unique mentoring opportunities. The Biology Department at USC has a total of 950 majors, of whom approximately 59% are women and 33% are minority students (27% are African American). An exchange program between USC and Dartmouth will allow promising young USC undergraduates to experience research in both the Guerinot and Connolly labs. First-generation, low-income undergraduate students from groups underrepresented in the sciences will be recruited and trained in the latest genomic, molecular and biochemical methods. The PI and co-PI are actively involved in a number of mentoring programs that will be supported by this grant.
