Identification and expression analysis of MAPK cascade gene family in foxtail millet (Setaria italica)

ABSTRACT

The mitogen-activated protein kinase (MAPK) cascade pathway is a highly conserved plant cell signaling pathway that plays an important role in plant growth and development and stress response. Currently, MAPK cascade genes have been identified and reported in a variety of plants including Arabidopsis thaliana, Oryza sativa, and Triticum aestivum, but have not been identified in foxtail millet (Setaria italica). In this study, a total of 93 MAPK cascade genes, including 15 SiMAPKs, 10 SiMAPKKs and 68 SiMAPKKKs genes, were identified by genome-wide analysis of foxtail millet, and these genes were distributed on nine chromosomes of foxtail millet. Using phylogenetic analysis, we divided the SiMAPKs and SiMAPKKs into four subgroups, respectively, and the SiMAPKKKs into three subgroups (Raf, ZIK, and MEKK). Whole-genome duplication analysis revealed that there are 14 duplication pairs in the MAPK cascade family in foxtail millet, and they are expanded by segmental replication events. Results from quantitative real-time PCR (qRT-PCR) revealed that the expression levels of most SiMAPKs and SiMAPKKs were changed under both exogenous hormone and abiotic stress treatments, with SiMAPK3 and SiMAPKK4–2 being induced under almost all treatments, while the expression of SiMAPKK5 was repressed. In a nutshell, this study will shed some light on the evolution of MAPK cascade genes and the functional mechanisms underlying MAPK cascade genes in response to hormonal and abiotic stress signaling pathways in foxtail millet (Setaria italica).

KEYWORDS:

• Foxtail millet (Setaria italica)
• MAPK cascade
• genome-wide identification
• gene expression analysis
• phylogenetic analysis

Acknowledgments

We would like to thank the reviewers, editors for their comments and suggestions.

Disclosure statement

No potential conflict of interest was reported by the authors.

CRediT authorship contribution statement

Teng-Guo Zhang and Sheng Zheng conceived and designed the study; Lu Zhang, Cheng Ma, and Xin Kang performed the bioinformatics analyses and the real-time quantitative PCR experiments; Zi-Qi Pei and Xue Bai helped to prepare figures and tables; Lu Zhang wrote the manuscript; Teng-Guo Zhang, Juan Wang, and Cheng Ma reviewed the manuscript. All authors have read and agreed to the published version of the manuscript.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15592324.2023.2246228

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (32060711, 31860054).