Transcriptome analysis revealed the drought-responsive genes in Tibetan hulless barley

Abstract

BackgroundHulless barley, also called naked barley, is an important cereal crop worldwide, serving as a healthy food both for human consumption and animal feed. Nevertheless, it often suffered from drought stress during its growth and development, resulting in a drastic reduction in barley yields. Therefore, study on molecular mechanism of hulless barley drought-tolerance is very important for increasing barley production. To investigate molecular mechanism of barley drought-resistance, this study examined co-regulated mRNAs that show a change in expression pattern under early well water, later water deficit and finally water recovery treatments, and to identify mRNAs specific to water limiting conditions.ResultsTotal of 853 differentially expressed genes (DEGs) were detected and categorized into nine clusters, in which VI and VIII were apparently up-regulated under low relative soil moisture content (RSMC) level. The majority of genes in these two clusters was relevant to abiotic stress responses in abscisic acid (ABA) dependent and independent signaling pathway, including NCED, PYR/PYL/RCAR, SnRK2, ABF, MYB/MYC, AP2/ERF family, LEA and DHN. In contrast, genes within clusters II and IV were generally down-regulated under water stress; cluster IX genes were up-regulated during water recovery response to both low and high RSMC levels. Genes in implicated in tetrapyrrole binding, photosystem and photosynthetic membrane were the most affected in cluster IX.ConclusionTaken together, our findings indicate that the responses of hulless barley to drought stress shows differences in the pathways and genes activated. Furthermore, all these genes displayed different sensitivities to soil water deficit and might be profitable for future drought tolerance improvement in barley and other crops.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-2685-3) contains supplementary material, which is available to authorized users.

The fifth leaf and spike organs of barley (Hordeum vulgare L.) display different physiological and metabolic responses to drought stress

“…Transcriptome studies have shown that genes for heat shock proteins (chaperones), late-embryogenesis abundant (LEA) proteins, osmolyte biosynthesis, ROS scavenging, signal transduction, defense, and others are up-regulated in response to drought [37–41]. These changes at the transcription level also increase accumulation of proteins and metabolites involved in drought resistance [42–45].…”

NJ cluster analysis of the SnRK2, PYR/PYL/RCAR, and ABF genes in Tibetan hulless barley

“…thaliana, S. bicolor, and O. sativa. We phylogenetically analyzed the three genes SnRK2, PYR/PYL/RCAR, and ABF. These three drought-resistance related genes in Tibetan hulless barley were available in the literature of Zeng et al (2016). Interestingly, we observed that SnRK2, PYR/PYL/RCAR, and ABF of Tibetan hulless barley were all associated with the corresponding genes in B. distachyon under certain experimental conditions.…”

“…RNA-Seq of Himalaya 10 under different relative soil moisture content levels has been carried out previously (Zeng et al, 2016). Based on results of the ABA signaling pathway relevant to drought stress from the RNA-Seq data, we selected gene sequences of SnRK2, PYR/PYL/RCAR, and ABF from the RNA-Seq data.…”

“…Yuan et al (2015) suggested that an up-regulation of the HbSINA4 gene was induced by drought stress in the Tibetan hulless barley cultivar, Himalaya 10. The ABA signal transduction pathway was found to be significantly different during the drought response process of Himalaya 10 (Zeng et al, 2016). In the present study, we phylogenetically analyzed and compared three drought-resistance related genes SnRK2, PYR/PYL/RCAR, and ABF from Tibetan hulless barley and another five model plant species.…”

Multiple transcriptional regulation of walnut JrGSTTau1 gene in response to osmotic stress

“…Considering that the induction is always a prediction for potential function (Wang et al , Yang et al , Zhao et al , Gao et al ) and upstream regulators such as the T. hispida eukaryotic translation initiation factor 1A ( TheIF1A ; Yang et al ), Phaseolus vulgaris Cd metal‐response element‐binding transcription factor 1 ( PvMTF‐1 ; Lin et al ), we can summarize that the drought‐inducing osmotic stress response of JrGSTTau1 is controlled by JrDREB2A , JrMYC2 , JrMYB44 , JrDof1 and JrWRKY7 , which may act as upstream regulators of JrGSTTau1 to either control JrGSTTau1 or act along with JrGSTTau1 to participate in plant drought stress response. Considering that the TFs of DREB, MYC, MYB, Dof and WRKY are members of a large family which have functions in plant osmotic stress responses, such as maize TaDREB3 (Shavrukov et al ), Tibetan hulless barley MYCs (Singh and Laxmi , Zeng et al ), Salicornia brachiata MYB44 (Shukla et al ), wheat TaMyb1D (Wei et al ), T. hispida Dof1.4 (Zang et al ), tomato SlCDF1‐5 (Corrales et al ), walnut JrWRKY7 and JrWRKY2 (Yang et al ). Therefore, based on these findings, we propose that the JrGSTTau1 gene is an important osmotic responsive gene and is involved in transcription pathways of DREB, MYC, MYB, Dof and WRKY.…”