Skip to main content
ARS Home » Research » Publications at this Location » Publication #179731

Title: PROTEIN OXIDATION IN LEAVES OF ARABIDOPSIS AND SOYBEAN: IMPLICATIONS FOR PLANT RESPONSE TO ELEVATED CO2.

Author
item QIU, QUANSHENG - UNIVERSITY OF ILLINOIS
item HUBER, JOAN - UNIVERSITY OF ILLINOIS
item Portis Jr, Archie
item Huber, Steven

Submitted to: Plant Biology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 2/28/2005
Publication Date: 4/1/2005
Citation: Qiu, Q., Huber, J.L., Portis Jr, A.R., Huber, S.C. 2005. Protein oxidation in leaves of arabidopsis and soybean: implications for plant response to elevated CO2. Plant Biology Annual Meeting. Available: http://abstracts/aspb.org/pb2005/public/P36/7475.html.

Interpretive Summary:

Technical Abstract: Plants are continually producing reactive oxygen species (ROS) that can irreversibly modify cellular components including proteins, resulting in DNPH-reactive carbonyl formation (hereafter referred to as protein oxidation). In both growth Arabidopsis and field-grown soybean leaves, numerous proteins were found to contain DNPH-reactive carbonyls, including Rubisco (LSU and SSU), Rubisco activase, and 25-kDa protein (see poster by Qiu et al.). In leaves of Arabidopsis plants grown at ambient CO2, protein oxidation levels remained relatively constant during vegetative and reproductive growth but increased late in reproductive development. Growth at elevated CO2 (1000 ppm) resulted in a dramatic increase in protein oxidation early in vegetative growth that was slowly reversed as plants developed until the overall level of oxidation was dramatically lower compared to plants grown at ambient CO2. Soybean leaves, grown in the field at SoyFACE, also had an overall lower level of protein oxidation when grown at elevated CO2. A new technique was developed to rapidly separate fraction I (Rubisco) from fraction II (non-Rubisco) proteins for 2-DE analysis that greatly enhances the ability to resolve and characterize leaf proteins, including those modified by oxidative stress. We are currently using MALDI-TOF mass spectrometry to identify proteins differing in abundance and/or level of oxidation from leaves grown at elevated CO2 compared to ambient CO2. Our working model is that growth at elevated CO2 results in an initial oxidation of proteins, and that with time plants acclimate, perhaps by increasing antioxidant capacity. This may explain why plants at elevated CO2 are more resistant to 03 injury.