This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
Leslie E. Sieburth IOS 0922288 BYPASS1 root-to-shoot signaling: the mobile signal interacts with the auxin pathway
Plants develop in an integrated manner, even though root and shoot systems are separated spatially and perceive different environmental conditions. For example, roots directly detect the soil compaction or drought, but unfavorable conditions also lead to altered shoot development. Physiological studies have shown that roots produce signaling molecules that move to the shoot, but how these signaling molecules modify shoot development is unknown. This project will investigate how shoot development is modulated by a root-derived long distance signal that is over-produced in Arabidopsis bypass1 mutants. This root-derived substance arrests leaf development. Recent data suggest that growth restriction occurs by reducing responses to auxin, an important plant hormone. The investigators will use molecular and physiological approaches to investigate hormone responses. Specific steps of the auxin response pathway will be analyzed using genetic and biochemical tools. This research program will reveal mechanistic detail of root-sourced signal interaction with auxin. Root-derived signals that limit shoot growth impose severe reductions in agriculture. Understanding of how shoot development programs are regulated by root-derived signals could lead to alternative agricultural practices that maximize productivity.
Broader impacts of this work are scientific (advancing our knowledge of signaling pathways, to be shared through publications and talks at conferences) and educational. Two undergraduate students, one from an under-served background, will be trained in genetics and molecular biology. One postdoctoral scholar will receive communication and teaching training. The postdoc and undergraduates will work together to develop a laboratory exercise for an undergraduate developmental biology class. This lab will provide hands-on experience with long distance signaling, and will be disseminated widely.