Haoqiang Yu1†, Bingliang Liu2†, Qinyu Yang1, Qingqing Yang1, Wanchen Li1*and Fengling Fu1*
DOI:10.1186/s12870-024-04923-x
Abstract
Background Molecular mechanisms in response to drought stress are important for the genetic improvement
of maize. In our previous study, nine ZmLAZ1 members were identified in the maize genome, but the function of
ZmLAZ1 was largely unknown.
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 the ZmLAZ1-3
gene in Arabidopsis significantly 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.
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