|Ainsworth, Elizabeth - Lisa|
Submitted to: New Phytologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/5/2012
Publication Date: 4/1/2012
Citation: Galant, A., Koester, R.P., Ainsworth, E.A., Hicks, L.M., Jez, J.M. 2012. From climate change to molecular response: redox proteomics of ozone-induced responses in soybean. New Phytologist. 194(1):220-229. Interpretive Summary: Soybean protein content and oxidation state were analzyed in leaf and root tissues of soybean exposed to ozone in a field setting. Ozone is a damaging reactive oxygen species that causes yield losses in sensitive crops. This study used a biochemical approach to examine which specific proteins were altered by growth at elevated ozone, and whether they were oxidized. Thirty-five proteins increased up to 5-fold in abundance with exposure to elevated ozone, 22 proteins showed up to 5-fold higher oxidation, and 22 proteins increased in both abundance and oxidation state. Proteins in pathways of carbon metabolism, photosynthesis, amino acid synthesis and antioxidant defense were altered. The study illustrates that the biochemical changes to long-term ozone fumigation are broad and affect many aspects of plant metabolism.
Technical Abstract: Ozone (O3) causes significant agricultural losses with soybean being highly sensitive to this oxidant. Here we assess the effect of elevated seasonal O3 exposure on the total and redox proteomes of soybean. To understand the molecular responses to O3 exposure, soybean grown at the Soybean Free Air Concentration Enrichment facility under ambient (37 ppb), moderate (58 ppb), and high (116 ppb) O3 concentrations was examined by redox-sensitive thiol labeling, mass spectrometry, and targeted enzyme assays. Proteomic analysis of soybean leaf tissue exposed to high O3 concentrations reveals widespread changes. In the high O3 leaf, 35 proteins increased up to 5-fold in abundance, 22 proteins showed up to 5-fold higher oxidation, and 22 proteins increased in both abundance and oxidation. These changes occurred in carbon metabolism, photosynthesis, amino acid synthesis, flavonoid and isoprenoid biosynthesis, signaling & homeostasis, and antioxidant pathways. This study shows that seasonal O3 exposure in soybean alters the abundance and/or oxidation state of multiple proteins across metabolism and provides a snapshot of biochemical acclimation to long-term O3 stress. Understanding how O3 affects redox-sensitive pathways may aid in the development of crops better adapted to this climate change.