Location: Children's Nutrition Research CenterTitle: Expression of a monothiol glutaredoxin, AtGRXS17, in tomato (Solanum lycopersicum) enhances drought tolerance
|Wu, Quingyu - Kansas State University|
|Hu, Ying - Kansas State University|
|Sprague, Stuart - Kansas State University|
|Kakeshpour, Tayebeh - Kansas State University|
|Park, Jungeun - Kansas State University|
|Cheng, Ninghui - Children'S Nutrition Research Center (CNRC)|
|Hirschi, Kendal - Children'S Nutrition Research Center (CNRC)|
|White, Frank - University Of Florida|
|Park, Sunghun - Kansas State University|
Submitted to: Biochemical and Biophysical Research Communications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2017
Publication Date: 9/30/2017
Citation: Wu, Q., Hu, Y., Sprague, S.A., Kakeshpour, T., Park, J., Nakata, P.A., Cheng, N., Hirschi, K.D., White, F.F., Park, S. 2017. Expression of a monothiol glutaredoxin, AtGRXS17, in tomato (Solanum lycopersicum) enhances drought tolerance. Biochemical and Biophysical Research Communications. 491:1034-1039.
Interpretive Summary: Drought is a major environmental conditions that results in the loss of billions of dollars in agricultural production each year. Thus, making plants more tolerant to drought would help reduce yield loss. When plants are exposed to drought reactive oxygen species (ROS) are produced. These ROS cause oxidative damage to the cells of the plant and lead to an inhibition of plant growth and even death. To reduce the damaging effects of ROS, plants often express glutaredoxins which are key regulators in the reduction of ROS. In this study we report that the expression of an Arabidopsis gene encoding one of these key regulators, glutaredoxin17, in tomato allows the tomato plant to better withstand drought. Biochemical measurements revealed that the engineered tomato plants not only had a reduction in oxidative damage, but also had twice the water content. In addition, tomato plants expressing this Arabidopsis gene also expressed other proteins, catalase and ABA-responsive binding protein 1, that help the plant cope with the lack of water. This new information coupled with our previous work showing that tomato plants over-expressing this same gene are tolerant to heat and cold is significant since it demonstrates that the introduction of this single Arabidopsis gene into tomato results in a tomato plant that is resistant to drought, heat, and cold.
Technical Abstract: Abiotic stresses are a major factor limiting crop growth and productivity. Our previous studies revealed that Arabidopsis thaliana glutaredoxin S17 (AtGRXS17) has conserved functions in plant tolerance to heat and chilling stress in tomato. Here, we report that ectopic expression of AtGRXS17 in tomato also enhanced tolerance to drought and oxidative stress. AtGRXS17-expressing tomato plants contained twice the shoot water content compared to wild-type plants under water limiting conditions. This enhanced drought tolerance correlated with a higher maximal photosynthetic efficiency of photosystem II (Fv/Fm). Ectopic AtGRXS17-expression was also found to induce the expression of Solanum lycopersicum catalase 1 (SlCAT1) and mitigated defects in the growth of primary roots in response to methyl viologen (MV) exposure. In addition, AtGRXS17 over-expression was found to prolong elevated expression levels of the Solanum lycopersicum ABA-responsive element binding protein 1 (SlAREB1) during drought stress. Overall, these findings demonstrate that over-expression of this single gene, AtGRXS17, can simultaneously improve the tolerance of tomato, and possibly other agriculturally important crops, to drought, heat, and cold stresses.