Iron deficiency anemia affects 2 billion people around the world, particularly in low-income countries where grains are the staple. Efforts to discover exactly how plants regulate the amount of iron they take up through their roots are now being led by Massachusetts Amherst molecular biologist Elsbeth Walker. Walker explains that plants have a regulatory mechanism to keep their iron content at a certain level, which makes it hard to make them carry more iron. Iron is an oxidant and causes cellular damage if not carefully controlled. Plants evolved signaling systems to communicate iron status in their tissues. Walker is now working to understand these signals. She is focusing on yellow-striped corn, a mutation whose stripes indicate iron starvation. Walker is sequencing the genome to find out where the mutation is. "There's no iron in the grain of rice," explains Walker. "There's iron in the leaves, but we don't eat the leaves. So we have to figure out how to get the iron to a place in the plant that we eat."

(Source: Crop Biotech Update, International Service for Acquisition of Agri-Biotech Applications.

Indian corn, a variant of maize. Professor Walker's group at UMass Amherst is studying maize with a yellow-stripe mutation, a symptom of a plant’s inability to “upload” sufficient iron. Photo Credit: UMass Amherst