microRNAs differentially modulated in response to heat and drought stress in durum wheat cultivars with contrasting water use efficiency

Abstract

Plant stress response is a complex molecular process based on transcriptional and posttranscriptional regulation of many stress-related genes. microRNAs are the best-studied class of small RNAs known to play key regulatory roles in plant response to stress, besides being involved in plant development and organogenesis. We analyzed the leaf miRNAome of two durum wheat cultivars (Cappelli and Ofanto) characterized by a contrasting water use efficiency, exposed to heat stress, and mild and severe drought stress. On the whole, we identified 98 miRNA highly similar to previously known miRNAs and grouped in 47 MIR families, as well as 85 novel candidate miRNA, putatively wheat specific. A total of 80 known and novel miRNA precursors were found differentially expressed between the two cultivars or modulated by stress and many of them showed a cultivar-specific expression profile. Interestingly, most in silico predicted targets of the miRNAs coming from the differentially expressed precursors have been experimentally linked in other species to mechanisms controlling stomatal movement, a finding in agreement with previous results showing that Cappelli has a lower stomatal conductance than Ofanto. Selected miRNAs were validated through a standardized and reliable stem-loop qRT-PCR procedure.

Unique miRNAs and their targets in tomato leaf responding to combined drought and heat stress

“…Candar-Cakir et al (2016) found that the expression of miRNAs from miR398 family were generally lower at drought treatment than control in upground tissues [21]. This is not the same case as our study, which could be explained by difference in the duration, intensity and approach of the drought stress as well as cultivar specificity [22]. Similarly, miR156 and miR167 family was induced by exposure to both moderately and acutely elevated temperatures (33 and 40°C) [6].…”

“…Therefore, the members from the same miRNA family may differently respond to abiotic stress including drought and heat, despite the similarity of each member [21,23]. MiR159 is a well-known responsive miRNA to heat stress [22]. We found that sly-miR159a-5p_gma and sly-miR159-p5 were down-regulated (− 4.16 and − 3.69 log 2 FC) in tomato at high temperature, which was in accordance with the results in wheat cultivar 'Ofanto' [22].…”

MicroRNAs in model and complex organisms

“…Considering the importance of miRNAs, this special issue focuses on some exciting research questions associated with functional roles of miRNAs both in animals and plants with the contribution of 18 valuable papers Azevedo-Pouly et al 2016;Baddela et al 2016;Deniz and Erman, 2016;Esmaeili et al 2016;Ferdous et al 2016;Giusti et al 2016;Gu et al 2016;Gupta et al 2017;Liu et al 2016;Qiu et al 2016;Reis et al 2016;Soltani et al 2016;Wang et al 2017;You et al 2017;Zhang et al 2016;Zhao et al 2016): How are the miRNAs involved in drought tolerance in plants? What is the role of miRNAs under biotic stress conditions?…”

“…In this special issue, Alptekin and colleagues reviewed the current progress about abiotic stress associated miRNAs and their targets as well the potential application of miRNA-based biotechnology on improvement of crop tolerance to abiotic stresses Zhang 2015), particularly in wheat and barley ). In addition, six research papers explore the miRNA response to abiotic stress as well as hormone treatment in several plant species (Esmaeili et al 2016;Ferdous et al 2016;Giusti et al 2016;Liu et al 2016;Gupta et al 2017;Zhao et al 2016) and detected miRNAs have shown that they play important roles in plant response to environmental adaptation. Liu and colleagues surveyed the miRNAs responsive to water-deficiency stress in four type of durum wheat (Liu et al 2016).…”

“…Ferdous and colleagues showed that overexpression of miR827 confers the drought tolerance in barley and it represented a potential for maintenance of drought tolerance in cereals (Ferdous et al 2016). In addition to the cereals, drought and osmotic stress associated miRNAs are also characterized in peach and almond (Esmaeili et al 2016;Giusti et al 2016). Also, Gupta and colleagues were analyzed and identified miRNAs and tasiRNAs under phosphate deficient conditions (Gupta et al 2017).…”