Iron Homeostasis in Plants

Iron is one of the most important and most problematic of all the micronutrients used by living organisms. Many of the mechanisms involved in plant iron homeostasis are not well understood, and this is a major obstacle to devising approaches for biofortification of staple foods with iron. Biofortification refers to the genetic engineering of staple crops to accumulate additional bioavailable iron in edible parts; it is widely regarded as a sustainable means of improving the iron nutrition of the 2-3 billion people worldwide whose inadequate diet causes iron deficiency anemia.

My group has a strong interest in the processes by which plants move iron and other transition metals within their above ground parts. We previously identified the Yellow Stripe1 Ys1 gene of maize, and showed that this transporter is responsible for primary uptake of iron. The identification of maize Ys1 led us to study the larger Yellow Stripe1-Like (YSL) family. Members of this transporter family are required for normal iron, zinc, and copper loading into both vegetative and reproductive tissues. At present, my group has a strong interest in the whole plant signaling processes that control iron uptake. In addition, we still seek to identify novel genes--especially in grasses--that participate in iron uptake and movement.