AUTHOR=Awan Samrah Afzal , Khan Imran , Tariq Rezwan , Rizwan Muhammad , Wang Xiaoshan , Zhang Xinquan , Huang Linkai 

TITLE=Genome-Wide Expression and Physiological Profiling of Pearl Millet Genotype Reveal the Biological Pathways and Various Gene Clusters Underlying Salt Resistance

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.849618

DOI=10.3389/fpls.2022.849618

ISSN=1664-462X

ABSTRACT=Pearl millet is a vital staple food and an important cereal crop used as food, feed, and forage. It can stand with heat and drought due to the presence of some unique genes; however, the mechanism of salt stress has been missing in pearl millet until now. Therefore, we conducted a comparative transcriptome profiling to reveal differentially expressed transcripts (DETs) associated with salt stress in pearl millet at different time points such as 1, 3, and 7 hours of salt treatment. Our physiological results suggested that salt stress significantly increased proline, malondialdehyde (MDA), hydrogen peroxide (H2O2) at 1, 3, and 7 hours of salt treatment. In addition, pearl millet plants regulated the activities of superoxide dismutase, catalase, and peroxidase to lessen the impact of salinity. Our transcriptomic results depicted that salt stress upregulated and downregulated the expression of various transcripts involved in different metabolic functions. At 1 and 7 hours of salt treatment, most of the transcripts were highly upregulated as compared to 3 hours treatment. Moreover, Among commonly enriched KEGG pathways, the MAPK signaling pathway and peroxisome pathway were significantly enriched. The DETs related to hormone signaling (auxins, ethylene, gibberellin, abscisic acid), kinases, protein modifications, and degradation were also identified, depicting the possible role of hormones and kinases to enhance plant tolerance against salt stress. Furthermore, the transcription factors including ERF, bHLH, HBP, MADS, MYB, and WRKY were predicted to significantly regulate different transcripts involved in salt stress responses at three different time points. Overall, this study will provide new insights better to understand the salt stress regulation mechanisms in pearl millet to improve its resistance against salinity and identify new transcripts that control these mechanisms in other cereals.