Systematic Analysis of Maize ZmbZIP Genes in Drought and Rewatering Transcriptomes

Abstract

The basic leucine zipper (bZIP) family of transcription factors (TFs) regulate diverse phenomena during plant growth and development and are involved in stress responses and hormone signaling. However, only a fewbZIPshave been functionally characterized. In this paper, 54 maizebZIPgenes were screened from previously published drought and rewatering transcriptomes. These genes were divided into nine groups in a phylogenetic analysis, supported by motif and intron/exon analyses. The 54 genes were unevenly distributed on 10 chromosomes and contained 18 segmental duplications, suggesting that segmental duplication events have contributed to the expansion of the maizebZIPfamily. Spatio-temporal expression analyses showed thatbZIPgenes are widely expressed during maize development. We identified 10 coreZmbZIPsinvolved in protein transport, transcriptional regulation, and cellular metabolism by principal component analysis, gene co-expression network analysis, and Gene Ontology enrichment analysis. In addition, 15 potential stress-responsive ZmbZIPs were identified by expression analyses. Localization analyses showed thatZmbZIP17,-33,-42, and-45are nuclear proteins. These results provide the basis for future functional genomic studies onbZIPTFs in maize and identify candidate genes with potential applications in breeding/genetic engineering for increased stress resistance. These data represent a high-quality molecular resource for selecting resistant breeding materials.Keywords:maize;basic leucine zipper;transcriptome analysis;duplication;abiotic stress;subcellular localization