Overexpression of GmNFYA5 confers drought tolerance to transgenic Arabidopsis and soybean plants

Xiao-Jun Ma,Ming Chen,Yong-Bin Zhou,Xin-You Cao,Zhao-Shi Xu,Xiao-Hui Li,Tai-Fei Yu,Jun Chen,Jun-Hua Zhang,You-Zhi Ma,Jian Ma

doi:10.1186/s12870-020-02337-z

Abstract

BackgroundCrop productivity is challenged by abiotic stresses, among which drought stress is the most common. NF-Y genes, especially NF-YA genes, regulate tolerance to abiotic stress.ResultsSoybean NF-Y gene GmNFYA5 was identified to have the highest transcript level among all 21 NF-YA genes in soybean (Glycine max L.) under drought stress. Drought-induced transcript of GmNFYA5 was suppressed by the ABA synthesis inhibitor naproxen (NAP). GmNFYA5 transcript was detected in various tissues at vegetative and reproductive growth stages with higher levels in roots and leaves than in other tissues, which was consist with the GmNFYA5 promoter: GUS fusion assay. Overexpression of GmNFYA5 in transgenic Arabidopsis plants caused enhanced drought tolerance in seedlings by decreasing stomatal aperture and water loss from leaves. Overexpression and suppression of GmNFYA5 in soybean resulted in increased and decreased drought tolerance, respectively, relative to plants with an empty vector (EV). Transcript levels of ABA-dependent genes (ABI2, ABI3, NCED3, LEA3, RD29A, P5CS1, GmWRKY46, GmNCED2 and GmbZIP1) and ABA-independent genes (DREB1A, DREB2A, DREB2B, GmDREB1, GmDREB2 and GmDREB3) in transgenic plants overexpressing GmNFYA5 were higher than those of wild-type plants under drought stress; suppression of GmNFYA5 transcript produced opposite results. GmNFYA5 probably regulated the transcript abundance of GmDREB2 and GmbZIP1 by binding to the promoters in vivo.ConclusionsOur results suggested that overexpression of GmNFYA5 improved drought tolerance in soybean via both ABA-dependent and ABA-independent pathways.

Highlights

Crop productivity is challenged by abiotic stresses, among which drought stress is the most common
Isolation and characterization of GmNFYA5 NF-YA genes mediate in drought stress tolerance [27, 28, 31]
Twenty one NF-YA genes were investigated in seedling leaves using qRT-PCR and most of them were induced by drought stress

Summary

Introduction

Crop productivity is challenged by abiotic stresses, among which drought stress is the most common. NF-Y genes, especially NF-YA genes, regulate tolerance to abiotic stress. Crop plants are commonly affected by abiotic stresses which cause soil destruction and crop losses worldwide [1, 2]. Either caused by drought or salt, is a major challenge. Drought is more widespread and damaging than salt stress [3]. Adaptation to drought involves complex regulatory networks involving control of water flux and cellular osmotic adjustment [4,5,6]. ABA regulates drought tolerance in plants by regulating stomatal aperture and modulating drought-responsive genes such as AP2/ERF and MYB family members that play important roles under drought stress [7,8,9]. ABA synthesis inhibitors such as naproxen and tungstate show the importance of ABA [10, 11]

Results

Discussion

Conclusion