ARS | Publication request: Think outside of the box: selenium volatilization altered by a broccoli gene in the ubiquinone biosynthetic pathway

Submitted to: Plant Signaling and Behavior
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 15, 2009
Publication Date: January 1, 2010
Citation: Zhou, X., Li, L. 2010. Think outside of the box: selenium volatilization altered by a broccoli gene in the ubiquinone biosynthetic pathway. Plant Signaling and Behavior. 5:74-75.

Interpretive Summary: Selenium is an essential micronutrient for animal and human nutrition, but becomes toxic at higher concentrations. Reducing the levels of selenium salts in selenium contaminated environments is of great importance. Recently, we have isolated a broccoli BoCOQ5-2 methyltransferase that promoted selenium volatilization in both bacteria and plants. We believe that the BoCOQ5-2 methyltransferase stimulates selenium volatilization through the production of ubiquinone to protect cells against oxidative stresses induced by selenium. Thus, alteration of oxidative stress tolerance could lead to new approaches to enhance selenium phytoremediation.

Technical Abstract: Selenium metabolism has been an area of active research because of the essentiality as well as toxicity of selenium to animals and humans. Biologically based selenium volatilization has been a particular area of interest for its potential in making detoxification of selenium pollution highly effective. Recently, we have isolated a broccoli BoCOQ5-2 methyltransferase gene involved in the ubiquinone biosynthetic pathway and found that it promoted selenium volatilization in both bacteria and plants. The identification of BoCOQ5-2 methyltransferase as a facilitator of selenium volatilization showed that selenium metabolism is regulated by other metabolic processes outside of the selenium/sulfur metabolic pathway. The interplay between ubiquinone and selenium metabolisms is possible through the protective function of ubiquinone against oxidative stresses induced by selenium. This observation could lead to new approaches to enhance selenium phytoremediation.