Location: Children's Nutrition Research CenterTitle: Arabidopsis monothiol glutaredoxin, AtGRXS17, is critical for temperature-dependent postembryonic growth and development via modulating auxin response) Author
Submitted to: Journal of Biological Chemistry
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/30/2011
Publication Date: 4/22/2011
Citation: Cheng, N.H., Liu, J., Liu, X., Wu, Q., Thompson, S.M., Lin, J., Chang, J., Whitham, S.A., Park, S., Cohen, J.D., Hirschi, K.D. 2011. Arabidopsis monothiol glutaredoxin, AtGRXS17, is critical for temperature-dependent postembryonic growth and development via modulating auxin response. Journal of Biological Chemistry. 286(23):20398-20406. Interpretive Summary: Global environmental temperature changes (global warming) threaten agriculture practice and food production. This study demonstrated that one type of antioxidant protein, called AtGRXS17, helps protect plants from high temperature. Therefore, these findings suggest that AtGRXS17 could be utilized to improve crop production and food quality under extreme environmental conditions.
Technical Abstract: Global environmental temperature changes threaten innumerable plant species. Although various signaling networks regulate plant responses to temperature fluctuations, the mechanisms unifying these diverse processes are largely unknown. Here, we demonstrate that an Arabidopsis monothiol glutaredoxin, AtGRXS17 (At4g04950), plays a critical role in redox homeostasis and hormone perception to mediate temperature-dependent postembryonic growth. AtGRXS17 expression was induced by elevated temperatures. Lines altered in AtGRXS17 expression were hypersensitive to elevated temperatures and phenocopied mutants altered in the perception of the phytohormone auxin. We show that auxin sensitivity and polar auxin transport were perturbed in these mutants, whereas auxin biosynthesis was not altered. In addition, atgrxs17 plants displayed phenotypes consistent with defects in proliferation and/or cell cycle control while accumulating higher levels of reactive oxygen species and cellular membrane damage under high temperature. Together, our findings provide a nexus between reactive oxygen species homeostasis, auxin signaling, and temperature responses.