Comparative Analysis of Heat-Tolerant and Heat-Susceptible Rice Highlights the Role of OsNCED1 Gene in Heat Stress Tolerance

Huang Zhou; Yingfeng Wang; Yijin Zhang; Yunhua Xiao; Xiong Liu; Huabing Deng; Xuedan Lu; Wenbang Tang; Guilian Zhang

doi:10.3390/plants11081062

Comparative Analysis of Heat-Tolerant and Heat-Susceptible Rice Highlights the Role of OsNCED1 Gene in Heat Stress Tolerance

Plants (Basel). 2022 Apr 13;11(8):1062. doi: 10.3390/plants11081062.

Authors

Huang Zhou^{1

2}, Yingfeng Wang^{1

2}, Yijin Zhang^{1

2}, Yunhua Xiao^{1

2}, Xiong Liu^{1

2}, Huabing Deng^{1

2}, Xuedan Lu^{1

2}, Wenbang Tang^{1

3}, Guilian Zhang^{1

2}

Affiliations

¹ College of Agronomy, Hunan Agricultural University, Changsha 410128, China.
² Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance, Hunan Agricultural University, Changsha 410128, China.
³ State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Centre, Changsha 410125, China.

Abstract

To elucidate the mechanism underlying the response of rice to heat stress (HS), the transcriptome profile of panicles was comparatively analyzed between the heat-tolerant line 252 (HTL252) and heat-susceptible line 082 (HSL082), two rice recombinant inbred lines (RILs). Our differentially expressed gene (DEG) analysis revealed that the DEGs are mainly associated with protein binding, catalysis, stress response, and cellular process. The MapMan analysis demonstrated that the heat-responsive (HR) genes for heat shock proteins, transcription factors, development, and phytohormones are specifically induced in HTL252 under HS. Based on the DEG analysis, the key gene OsNCED1 (Os02g0704000), which was induced under HS, was selected for further functional validation. Moreover, 9-cis-epoxycarotenoid dioxygenase (NCED) is a key rate-limiting enzyme in the ABA biosynthetic pathway. Overexpression of OsNCED1 improved the HS tolerance of rice at the heading and flowering stage. OsNCED1-overexpression plants exhibited significant increases in pollen viability, seed setting rate, superoxide dismutase (SOD) and peroxidase (POD) activities, while significantly lower electrolyte leakage and malondialdehyde (MDA) content relative to the wild type (WT). These results suggested that OsNCED1 overexpression can improve the heat tolerance of rice by enhancing the antioxidant capacity. Overall, this study lays a foundation for revealing the molecular regulatory mechanism underlying the response of rice to prolonged HS.

Keywords: OsNCED1; antioxidant enzyme; heading and flowering stage; heat stress; rice; transcriptome.

Abstract

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