Transcriptome profile reveals drought induced genes preferentially expressed in response to water deficit in cultivated peanut (Arachis hypogaea L.)

Authors: WANG, XU - Auburn University; YANG, XINLEI - Auburn University; FENG, YUCHENG - Auburn University; Dang, Phat; WANG, WENWEN - Auburn University; GRAZE, RITA - Auburn University; CLEVENGER, JOSH - Hudsonalpha Institute For Biotechnology; CHU, YE - University Of Georgia; OZIAS-AKINS, PEGGY - University Of Georgia; Holbrook, Carl - Corley; CHEN, CHARLES - Auburn University

Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/12/2021
Publication Date: 4/30/2021
Citation: Wang, X., Yang, X., Feng, Y., Dang, P.M., Wang, W., Graze, R., Clevenger, J., Chu, Y., Ozias-Akins, P., Holbrook Jr, C.C., Chen, C. 2021. Transcriptome profile reveals drought induced genes preferentially expressed in response to water deficit in cultivated peanut (Arachis hypogaea L.). Frontiers in Plant Science. 12:645291. https://doi.org/10.3389/fpls.2021.645291.
DOI: https://doi.org/10.3389/fpls.2021.645291

Interpretive Summary: Cultivated peanut is one of the most widely grown food legumes in the world being valued for its high protein and unsaturated oil contents. Drought stress is one of the major constraints that limits peanut production. The objective of this study was to identify the drought responsive genes preferentially controlled under drought stress in different peanut lines. To accomplish this, four lines (2 drought tolerant lines: C76-16 and 587; 2 drought susceptible lines: Tifrunner and 506) were subjected to drought stress utilizing environmentally controlled rainout shelters. Genetic sequencing analysis identified a total of 2,457 drought regulated genes that were shared by all four lines. These were sorted into 139 categories consisting of 86 biological processes and 53 molecular functions, with defense response, reproductive process and signaling pathways. In addition, 3,576 drought regulated genes were identified only in drought tolerant lines mainly related to protein modification process, pollination, and metabolic process. This research identified regulated genes that are shared by both tolerant and susceptible lines under drought stress, in drought tolerant lines only, and in drought susceptible lines only. Furthermore, enriched biological pathways for a similar comparison identified important peanut drought tolerant processes. This research expands our current understanding of the mechanisms that facilitate peanut drought tolerance and shed light on breeding advanced peanut lines to combat drought stress.

Technical Abstract: Cultivated peanut (Arachis hypogaea) is one of the most widely grown food legumes in the world being valued for its high protein and unsaturated oil contents. Drought stress is one of the major constraints that limits peanut production. The objective of this study was to identify the drought responsive genes preferentially expressed under drought stress in different peanut genotypes. To accomplish this, four genotypes (drought tolerant: C76-16 and 587; drought susceptible: Tifrunner and 506) subjected to drought stress in a rainout shelter experiment were examined. Transcriptome sequencing analysis identified that a total of 2,457 differentially expressed genes (DEGs) were shared by all four genotypes. A total of 139 enriched gene ontology (GO) terms consisting of 86 biological processes and 53 molecular functions, with defense response, reproductive process and signaling pathways were significantly enriched in the common DEGs. In addition, 3,576 DEGs were identified only in drought tolerant lines in which a total of 74 GO terms were identified, including 55 biological processes and 19 molecular functions, mainly related to protein modification process, pollination, and metabolic process. These terms were also found in shared genes in four genotypes, indicating that tolerant lines adjusted more related genes to respond to drought. Forty-three significantly enriched Kyoto encyclopedia of genes and genomes (KEGG) pathways were also identified, and the most enriched pathways were those processes involved in metabolic pathways, biosynthesis of secondary metabolites, plant circadian rhythm, phenylpropanoid biosynthesis, starch and sucrose metabolisms. This research expands our current understanding of the mechanisms that facilitate peanut drought tolerance and shed light on breeding advanced peanut lines to combat drought stress.