Genome-wide identification of sucrose non-fermenting-1-related protein kinase genes in maize and their responses to abiotic stresses.

Introduction: Protein kinases play an important role in plants in response to environmental changes through signal transduction. As a large family of protein kinases, sucrose non-fermenting-1 (SNF1)-related kinases (SnRKs) were found and functionally verified in many plants. Nevertheless, little is known about the family of .

Methods: Evolutionary relationships, chromosome locations, gene structures, conserved motifs, and cis-elements in promoter regions were systematically analyzed. Besides, tissue-specific and stress-induced expression patterns of were determined. Finally, functional regulatory networks between and other proteins or miRNAs were constructed.

Results And Discussion: In total, 60 genes located on 10 chromosomes were discovered in maize. were classified into three subfamilies (, , and ), consisting of 4, 14, and 42 genes, respectively. Gene structure analysis showed that 33 of the 42 genes contained only one exon. Most genes contained at least one ABRE, MBS, and LTR cis-element and a few genes had AuxRR-core, P-box, MBSI, and SARE ciselements in their promoter regions. The Ka:Ks ratio of 22 paralogous gene pairs revealed that the gene family had experienced a purifying selection. Meanwhile, we analyzed the expression profiles of , and they exhibited significant differences in various tissues and abiotic stresses. In addition, A total of eight ZmPP2Cs, which can interact with proteins, and 46 miRNAs, which can target 24 , were identified. Generally, these results provide valuable information for further function verification of , and improve our understanding of the role of in the climate resilience of maize.