Iron Deficiency Signaling in Soybean: Root and Shoot Interactions

Iron Deficiency Chlorosis (IDC) is an important problem for soybeans grown in the upper Midwestern United States. We are leveraging genomic resources for soybean, including transcriptomic studies and virus induced gene silencing (VIGS), to characterize soybean’s iron deficiency response. Transcriptomic studies of roots and leaves at 30, 60 and 120 minutes after iron stress have identified thousands of differentially expressed genes (DEGs). While there is little overlap in individual gene expression between time points and tissue types, we observe the same biological pathways being affected after both short and long term iron stress exposure. These studies highlight the importance of iron homeostasis genes, DNA replication and defense in protecting soybean against IDC. Looking at gene expression at these early time points, has allowed us to characterize early signaling events between shoots and roots, controlled by novel suites of transcription factors briefly activated within these time points. These studies highlight the unique aspects of IDC responses in soybean and other crops.