Transcriptomes of early developing tassels under drought stress reveal differential expression of genes related to drought tolerance in maize

Abstract

The development of tassels, the male reproductive organs in maize, is adversely affected by drought during tasseling. To investigate drought tolerance mechanisms at the transcriptome level during early tassel differentiation, RNA-Seq was performed using RNA isolated from early developing tassels sampled from 10 drought-stressed maize inbred lines and their corresponding well-watered treatment (control). The most active pathways were related to metabolic regulation at the RNA level. Expression of genes encoding enzymes involved in carbohydrate and lipid metabolism was significantly downregulated in tassels of drought-stressed plants. Transcription factors and genes encoding catabolic or degradative enzymes were over-expressed in maize early developing tassels under drought-stressed conditions. Among them, transcripts of genes annotated as encoding exon-junction complexes involved in 'RNA transcript' and 'mRNA surveillance' pathways were identified as significantly affected by drought stress. Many other important genes whose expression responds to drought stress were also identified to reflect the transcriptional changes at the later period of stress.

Global transcriptome and weighted gene co-expression network analyses of growth-stage-specific and hybrid-cultivar-specific drought stress responses in maize

“…Particularly in maize, several drought stress response studies have employed the use of RNA-seq technology. The gene expression profiles of maize developing tassels under water deficit conditions were monitored and the results indicated that the up-regulated genes involved in carbohydrate and lipid metabolism were critical in effecting drought tolerance [31]. Moreover, in our previous study, we highlighted the role protein ubiquitination play in coordinating cellular crosstalk between stress and hormone signaling in maize seedlings under drought stress conditions [32].…”

Comparative transcriptomic analysis of contrasting hybrid cultivars reveal key drought-responsive genes and metabolic pathways regulating drought stress tolerance in maize at various stages

“…More remarkably, the 'response to abiotic stimulus' and 'response to stress' related DEGs in cluster 7, including HSPs, DHNs, PRs, AP2-EREBP and WRKY, showed high expression under drought conditions at the VT stage, but low expression at the V12, R2 and R4 stages (S4 Table). A large number of researches have reported these stress responsive genes to play vital roles in maize drought stress response [21,22]. Meanwhile, as for the R2 stage, plant hormone signaling related genes in cluster 4, including brassionosteroid receptors (BRs) and ABA; NAC-transcription; and stress-induced protein, PRs were down-regulated.…”

“…Transcriptome analysis using RNA-sequencing (RNA-seq) has offered us convenience in detecting novel genes in a tissue-or cell-specific manner and enabled us to identify transcriptomic changes under certain biological conditions [19]. RNA-seq has been successfully applied in global gene expression profiling in maize response to drought stress [20][21][22]. Despite all this progress, however, most of these transcriptome researches in maize have focused on a single stage separately, especially the seedling [22], vegetative [20] or reproductive [19] stages.…”

Comparative proteomics analysis of two maize hybrids revealed drought-stress tolerance mechanisms

“…Plants are subjected to a variety of environmental pressures throughout their life cycles, for example, cold, heat, drought, salt, etc., which have a significant impact on plant activities and the formation of crop yields [1][2][3][4][5]. Recent studies have shown that drought is the major environmental determinant of plant productivity; the drought-induced crop losses nearly equal to those caused by all other natural disasters combined [6][7][8].…”