RNA-Seq Reveals Waterlogging-Triggered Root Plasticity in Mungbean Associated with Ethylene and Jasmonic Acid Signal Integrators for Root Regeneration

Abstract

Global climate changes increase the frequency and intensity of heavy precipitation events, which result in flooding or soil waterlogging. One way to overcome these low-oxygen stresses is via modifying the plant root system to improve internal aeration. Here, we used a comparative RNA-seq based transcriptomic approach to elucidate the molecular mechanisms of waterlogging-triggered root plasticity in mungbean (Vigna radiata), a major grain legume cultivated in Asia. Two mungbean varieties with contrasting waterlogging tolerance due to the plasticity of the root system architecture were subjected to short-term and long-term waterlogging. Then, RNA-seq was performed. Genes highly expressed in both genotypes under short-term waterlogging are related to glycolysis and fermentation. Under long-term waterlogging, the expression of these genes was less induced in the tolerant variety, suggesting it had effectively adapted to waterlogging via enhancing root plasticity. Remarkably, under short-term waterlogging, the expression of several transcription factors that serve as integrators for ethylene and jasmonic acid signals controlling root stem cell development was highly upregulated only in the tolerant variety. Sequentially, root development-related genes were more expressed in the tolerant variety under long-term waterlogging. Our findings suggest that ethylene and jasmonic acids may contribute to waterlogging-triggered root plasticity by relaying environmental signals to reprogram root regeneration. This research provides the basis for the breeding and genetic engineering of waterlogging-tolerant crops in the future.

Elucidating the molecular responses to waterlogging stress in onion (Allium cepa L.) leaf by comparative transcriptome profiling

“…However, it is possible that some sort of signaling from the roots induced the expression of fermentation-related genes such as PDC and ADH in the leaves. Similar findings have also been reported in mungbean and cotton, where the induced expression of PDC and ADH was observed in the leaves when the roots were subjected to hypoxic conditions ( Sreeratree et al., 2022 ; Christianson et al., 2010 ). Photosynthesis is highly sensitive to waterlogging stress, and several transcripts related to photosynthesis were differentially expressed in onion due to waterlogging.…”

Ethylene and Jasmonates Signaling Network Mediating Secondary Metabolites under Abiotic Stress

“…Moreover, during reoxygenation, most of the genes related to JA biosynthesis were up-regulated as well as antioxidant-related genes, such as VTC genes or GSH genes, which encode for ascorbate (vitamin C) and glutathione, respectively. Recently, JA-related transcription factors were up-regulated in a waterlogging-tolerant species ( Vigna radiata ) under short-term waterlogging [ 174 ].…”

Thirty Years of Mungbean Genome Research: Where Do We Stand and What Have We Learned?

“…Before 2000, there was only one transcriptomics study on mungbean (Chen et al, 2008). When the cost of NGS became affordable around the mid-2010s, the number of transcriptomics sequencing studies on mungbean increased sharply (Moe et al, 2011;Chen et al, 2015;Li et al, 2015;Lin et al, 2016;Liu M. S. et al, 2016;Tian et al, 2016;Kumar et al, 2020;Chang et al, 2021;Dasgupta et al, 2021;Hu et al, 2022;Sreeratree et al, 2022;Sudha et al, 2022;Zhao et al, 2022). The majority of these transcriptome analyses were related to responses to biotic and abiotic stresses, for example, drought, chilling temperature, waterlogging, heat, bruchids (C. chinensis), and Fusarium wilt (Fusarium oxysporum).…”