Differential Expression of Maize and Teosinte microRNAs under Submergence, Drought, and Alternated Stress

Abstract

Submergence and drought stresses are the main constraints to crop production worldwide. MicroRNAs (miRNAs) are known to play a major role in plant response to various stresses. In this study, we analyzed the expression of maize and teosinte miRNAs by high-throughput sequencing of small RNA libraries in maize and its ancestor teosinte (Zea mays ssp. parviglumis), under submergence, drought, and alternated stress. We found that the expression patterns of 67 miRNA sequences representing 23 miRNA families in maize and other plants were regulated by submergence or drought. miR159a, miR166b, miR167c, and miR169c were downregulated by submergence in both plants but more severely in maize. miR156k and miR164e were upregulated by drought in teosinte but downregulated in maize. Small RNA profiling of teosinte subject to alternate treatments with drought and submergence revealed that submergence as the first stress attenuated the response to drought, while drought being the first stress did not alter the response to submergence. The miRNAs identified herein, and their potential targets, indicate that control of development, growth, and response to oxidative stress could be crucial for adaptation and that there exists evolutionary divergence between these two subspecies in miRNA response to abiotic stresses.

Identification of novel drought-responsive miRNA regulatory network of drought stress response in common vetch (Vicia sativa)

“…MicroRNAs regulate gene expression by up- or downregulating target genes. Numerous studies have revealed the expression patterns of miRNAs and their target genes under plant drought stress through high-throughput sequencing [ 52 , 62 ]. Herein, a large data set of miRNAs was obtained.…”

Recent developments in multi-omics and breeding strategies for abiotic stress tolerance in maize (Zea mays L.)

“…For example, a microarray expression analysis of a drought-associated study revealed 13 miRNAs families regulating 42 novel mRNAs target and 65 in maize (Li et al, 2020). Another study showed that 23 drought-responsive cis-regulatory elements and three TFs (GAMYB, HD-Zip III, and NAC) were associated with the target mRNAs (Aravind et al, 2017;Sepúlveda-García et al, 2020). The knock-down maize mutants of miR166 showed its association with adaptation through various phenotypic variations.…”

‘Against all floods’: plant adaptation to flooding stress and combined abiotic stresses

“…Importantly, chronological order of stresses largely influenced corresponding plant responses, for example, wild maize (teosinte) plants first treated with drought and then exposed to flooding behaved like flooded‐only plants. The opposite stress order attenuated the drought response, most likely due to the harmful effect of reoxygenation on plant survival (Sepúlveda‐García et al., 2020). Flood‐tolerant willows or adult Chloris gayana , a forage crop grass, acted oppositely and showed little physiological change under flooding stress independent of previous stresses, while staying susceptible to drought stress (Doffo et al., 2017; Mollard et al., 2022).…”