9- cis-epoxycarotenoid dioxygenase 1 confers heat stress tolerance in rice seedling plants

Yijin Zhang; Xiong Liu; Rui Su; Yunhua Xiao; Huabing Deng; Xuedan Lu; Feng Wang; Guihua Chen; Wenbang Tang; Guilian Zhang

doi:10.3389/fpls.2022.1092630

9- cis-epoxycarotenoid dioxygenase 1 confers heat stress tolerance in rice seedling plants

Front Plant Sci. 2022 Dec 20:13:1092630. doi: 10.3389/fpls.2022.1092630. eCollection 2022.

Authors

Yijin Zhang^{1

2}, Xiong Liu^{1

2}, Rui Su^{1

2}, Yunhua Xiao^{1

2}, Huabing Deng^{1

2}, Xuedan Lu^{1

2}, Feng Wang^{1

2}, Guihua Chen¹, Wenbang Tang^{1

2

3

4}, Guilian Zhang^{1

2}

Affiliations

¹ College of Agronomy, Hunan Agricultural University, Changsha, China.
² Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance, Changsha, China.
³ Hunan Hybrid Rice Research Center, Hunan Academy of Agricultural Sciences, Changsha, China.
⁴ State Key Laboratory of Hybrid Rice, Changsha, China.

Abstract

High temperature is one of the main constraints affecting plant growth and development. It has been reported that abscisic acid (ABA) synthesis gene 9-cis-epoxycarotenoid dioxygenase (NCED) positively regulates plant resistance to salt, cold, and drought stresses. However, little is known about the function of the NCED gene in heat tolerance of rice. Here, we found that OsNCED1 was a heat stress inducible gene. Rice seedlings overexpressing OsNCED1 showed enhanced heat tolerance with more abundant ABA content, whereas the knockout mutant osnced1 accumulated less ABA and showed more sensitive to heat stress. Under heat stress, increased expression of OsNCED1 could reduce membrane damage and reactive oxygen species (ROS) level of plants, and elevate the activity of antioxidant enzymes. Moreover, real time-quantitative PCR (RT-qPCR) analysis showed that overexpression of OsNCED1 significantly activated the expression of genes involved in antioxidant enzymes, ABA signaling pathway, heat response, and defense. Together, our results indicate that OsNCED1 positively regulates heat tolerance of rice seedling by raising endogenous ABA contents, which leads to the improved antioxidant capacity and activated expression of heat and ABA related genes.

Keywords: ABA; OsNCED1; heat stress; rice; seedling.