Maize ZmLAZ1-3 gene negatively regulates drought tolerance in transgenic Arabidopsis

Haoqiang Yu1†, Bingliang Liu2†, Qinyu Yang1, Qingqing Yang1, Wanchen Li1*and Fengling Fu1*

Abstract

Background Molecular mechanisms in response to drought stress are important for the genetic improvement

of maize. In our previous study, nineZmLAZ1members were identified in the maize genome, but the function of

ZmLAZ1was largely unknown.

Results The ZmLAZ1-3gene was cloned from B73, and its drought-tolerant function was elucidated by expression

analysis in transgenicArabidopsis. The expression ofZmLAZ1-3was upregulated by drought stress in different maize

inbred lines. The driving activity of theZmLAZ1-3promoter was induced by drought stress and related to the abiotic

stress-responsive elements such as MYB, MBS, and MYC. The results of subcellular localization indicated that the

ZmLAZ1-3 protein localized on the plasma membrane and chloroplast. The ectopic expression of theZmLAZ1-3

gene inArabidopsissignificantly reduced germination ratio and root length, decreased biomass, and relative water

content, but increased relative electrical conductivity and malondialdehyde content under drought stress. Moreover,

transcriptomics analysis showed that the differentially expressed genes between the transgenic lines and wild-type

were mainly associated with response to abiotic stress and biotic stimulus, and related to pathways of hormone

signal transduction, phenylpropanoid biosynthesis, mitogen-activated protein kinase signaling, and plant-pathogen

interaction.

Conclusion The study suggests that theZmLAZ1-3gene is a negative regulator in regulating drought tolerance and

can be used to improve maize drought tolerance via its silencing or knockout.

Keywords 

Ectopic expression, Drought, Maize, ZmLAZ1-3