Functional Characterization of the Arabidopsis Thaliana ARG1 Gene Involved in Gravity Signal Transduction

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

A grant has been awarded to Dr. Patrick H. Masson of the University of Wisconsin-Madison, to characterize proteins involved in gravitropism, a physiological process that allows plant organs to use gravity as a growth guide. In most plants, gravitropism dictates upward shoot growth above ground, and downward root growth into the soil. It allows shoots to reach light, and roots to take up water and mineral ions. Unfortunately, very little is known about the molecular mechanisms underlying this complex physiological response. Dr. Masson's group has identified and characterized a group of proteins that are essential for gravitropism in the model plant Arabidopsis thaliana. These proteins are structurally related to a subgroup of chaperone proteins found in all organisms, which have been implicated in the folding, trafficking and assembly of protein complexes involved in specific cellular and developmental processes, as well as in responses to environmental stimuli. Using molecular genetic and biochemical procedures, Masson's research team will characterize proteins that are affected by these chaperones, and define their roles in gravity signal transduction. These studies will enhance our understanding of the molecular mechanisms that allow specific molecular chaperones to modulate gravity signal transduction in plants. In turn, this information may have profound implications for our understanding of the role played by such molecules in other systems, such as mammals. This project may also result in important agricultural applications in the long term. Indeed, gravitropism has important consequences for agricultural productions. For instance, agriculture encounters large production losses every year, due to plant prostration by wind or heavy rains (lodging). A better understanding of the molecular mechanisms that govern gravitropism may, in the long term, provide the information and tools needed to improve agricultural practices aimed at reducing lodging, or engineer plants that better resist to wind and rain. Finally, this project will have an important educational component to it, as it will involve the training of a postdoctoral fellow, assisted by graduate, undergraduate and high school students.