Our long-term research ambitions are to (i) identify and characterize components of the cellular machinery used by plants to detect and respond to the hormone auxin, and (ii) to use this knowledge to develop fluorescence-based “biosensors” that enable accurate measurement of hormone levels and location in living plants.

Current Projects

Maize_AuxRE_logoMaize AuxRE (supported by the NSF)

The Maize AuxRE collaboration is focused on defining auxin-regulated molecular networks in the economically important crop plant, maize (corn), and to link these networks to the growth and development of its reproductive structures, the tassel and the ear, key factors in maize productivity. Connecting auxin signaling modules with tissue-level events will require a detailed understanding of which interactions occur in specific tissues and at specific times. One way we are approaching functional analysis of the auxin signaling interactome is through a synthetic auxin signaling system in yeast. This systems enables co-expression of user-defined auxin signaling modules: receptors, repressors, transcription factors, and transcription factor binding sites. Auxin-induced signaling dynamics can then be measured for each module, providing information on sensitivity to auxin levels and the speed and magnitude of the auxin response.

Auxin Biosensor (supported by the M.J. Murdock Charitable Trust, Beckman Scholars Program, & Whitman College)

We are also designing and testing new fluorescent auxin biosensors. A biosensor is an analytical device made out of biological materials such as DNA or proteins, which in turn readily enables it for use in living cells/organisms. We build and test new auxin biosensor designs in yeast, and strong candidates will then be tested in plants.