05/24/2012
Understanding Plant Hormones
The Science
Plants respond to developmental cues and environmental stresses by controlling both the level and activity of various hormones. A highly adaptable scaffold enables the evolution of promiscuous activity within the auxin-responsive GH3 enzyme family, leading to diversification of substrate specificity and evolution of metabolic control systems. Newly reported crystal structures provide a glimpse into substrate recognition and control of hormones involved in plant growth, development, and defense, enabling deeper understanding of plant metabolism intricacies. The research was conducted using resources at the Advanced Photon Source at Argonne National Laboratory.
Summary
This research reported the crystal structures for two acyl acid amido synthetases from Arabidopsis. The findings suggest how the enzymes might discriminate between apolar and acidic amino acids and lend insight into the reaction chemistries that add functional diversity to hormone signaling pathways. These results demonstrate how a highly adaptable three-dimensional scaffold is used for the evolution of promiscuous activity across an enzyme family for modulation of plant signaling molecules.
BER Program Manager
Amy Swain
U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]
References
Westfall, C. S., C. Zubieta, J. Herrmann, U. Kapp, M. H. Nanao, and J. M. Jez. 2012. “Structural Basis for Prereceptor Modulation of Plant Hormones by GH3 Proteins,” Science 336, 1708–11. DOI:10.1126/science.1221863.