HvbZIP21, a Novel Transcription Factor From Wild Barley Confers Drought Tolerance by Modulating ROS Scavenging

Rui Pan; Sebastian Buitrago; Zhenbao Feng; Salah Fatouh Abou-Elwafa; Le Xu; Chengdao Li; Wenying Zhang

doi:10.3389/fpls.2022.878459

HvbZIP21, a Novel Transcription Factor From Wild Barley Confers Drought Tolerance by Modulating ROS Scavenging

Front Plant Sci. 2022 Apr 22:13:878459. doi: 10.3389/fpls.2022.878459. eCollection 2022.

Authors

Rui Pan¹, Sebastian Buitrago¹, Zhenbao Feng¹, Salah Fatouh Abou-Elwafa², Le Xu¹, Chengdao Li³, Wenying Zhang¹

Affiliations

¹ Research Center of Crop Stresses Resistance Technologies/Hubei Collaborative Innovation Center for Grain Industry, Yangtze University, Jingzhou, China.
² Department of Agronomy, Faculty of Agriculture, Assiut University, Assiut, Egypt.
³ Western Crop Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA, Australia.

Abstract

Drought stress is a common environmental stress, which adversely affects the yield and quality of crops. Due to its excellent drought tolerance, wild barley from the Middle East region is considered a valuable source for barley improvement. Here, we compared the growth rate, stomatal regulation and capacity to metabolize reactive oxygen species (ROS) of two barley cultivars and one wild barley accession. The results indicated the wild barley EC_S1 showed a more significant decline in stomatal aperture and less ROS production. Transcriptomic analysis revealed that EC_S1 has slower transcriptional regulation (5,050 DEGs) in the early stage of drought stress (14 days) than Baudin (7,022 DEGs) and Tadmor (6,090 DEGs). In addition, 30 hub genes, including nine known drought-related genes were identified by WGCNA analysis. Then, we cloned a novel bZIP transcription factor, HvbZIP21, from EC_S1. HvbZIP21 was subcellularly targeted to the nucleus. Overexpression of HvbZIP21 in Arabidopsis enhanced drought tolerance due to increasing activities of superoxide dismutase, peroxidase, and catalase activities as well as glutathione content. Silencing of HvbZIP21 in EC_S1 suppressed drought tolerance in BSMV:HvbZIP21-inoculated plants. Taken together, our findings suggest that HvbZIP21 play a critical role in drought tolerance by manipulating ROS scavenging.

Keywords: Hordeum spontaneum; basic leucine zipper; reactive oxygen species; virus-induced gene silencing; water deficit.