MicroRNAs (miRNAs) are important players in post-transcriptional gene expression regulation in multicellular species. miRNAs can modify/decrease the expression of fully or partially complementary mRNA molecules. Plant miRNAs are powerful regulators of gene expression at the post-transcriptional level, which was repeatedly proved in several model plant species. miRNAs are considered to be key regulators of many developmental, homeostatic, and immune processes in plants.


| Title of the Study and Reference | Barley Cultivars Inspected |
Year of | Publication | Most Important Findings | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Regulation of barley miRNAs upon dehydration stress correlated with target gene expression | [56] | Hordeum vulgare | 2010 | A total of 28 potential miRNAs were identified using bioinformatic approaches (BLASTn of known plant miRNAs and barley expressed sequence tags (ESTs), and RNA folding algorithms). | |||||||||
| Discovery of barley miRNAs through deep sequencing of short reads | [69] | Hordeum vulgare | cultivars Golden Promise and Pallas | 2011 | The first large-scale study of miRNAs in | Hordeum Vulgare | , 100 miRNAs were identified (only 56 of them had orthologs in wheat, rice, or Brachypodium) and 3 candidates were validated in vitro using a Northern blot assay. | ||||||
| Identification and Characterization of MicroRNAs from Barley ( | Hordeum vulgare | L.) by High-Throughput Sequencing | [70] | Hordeum vulgare | L. | 2012 | 126 conserved miRNAs (belonging to 58 families), and 133 novel miRNAs (50 families) were identified in this study. | ||||||
| miRNA regulation in the early development of barley seed | [38] | Hordeum vulgare | 2012 | 84 known miRNAs and 7 new miRNAs together with 96 putative miRNA target genes were identified during the early development of barley seeds (first 15 days post anthesis). | |||||||||
| Developmentally regulated expression and complex processing of barley pri-microRNAs | [71] | Hordeum vulgare | cultivar Rolap | 2013 | miRNA genes in barley often contain introns which may play important role in miRNA processing. | ||||||||
| A Comprehensive Expression Profile of MicroRNAs and Other Classes of Non-Coding Small RNAs in Barley Under Phosphorous-Deficient and -Sufficient Conditions | [61] | Hordeum vulgare | L., cultivar Pallas | 2013 | 221 conserved miRNAs and 12 novel miRNAs were identified, many of them were phosphorus condition-specific. A total of 47 miRNAs were significantly differentially expressed between the two phosphorus treatments. | ||||||||
| Boron Stress Responsive MicroRNAs and Their Targets in Barley | [60] | Hordeum vulgare | L. cultivar Sahara | 2013 | 31 known and 3 new miRNAs were identified in barley, and 25 of them were found to respond to boron treatment. | ||||||||
| Transcriptionally and post-transcriptionally regulated microRNAs in heat stress response in barley | [67] | Hordeum vulgare | cultivar Rolap | 2014 | Four heat stress up-regulated barley miRNAs were found (miR160a, miR166a, miR167h, and miR5175a). | ||||||||
| Differential expression of microRNAs and other small RNAs in barley between water and drought conditions | [57] | Hordeum vulgare | cultivar Golden Promise | 2014 | Three novel miRNAs, designated as hvu-miRX33, hvu-miRX34, and hvu-miRX35 were identified. hvu-miRX34 had no homologous miRNA in wheat. | ||||||||
| The miR9863 Family Regulates Distinct Mla Alleles in Barley to Attenuate NLR Receptor-Triggered Disease Resistance and Cell-Death Signaling | [72] | Hordeum vulgare | L. | 2014 | The key role of the miR9863 family in the immune response to the pathogen (powdery mildew fungus, | Blumeria graminis | f. sp. | hordei | ) was proposed | ||||
| Polycistronic artificial miRNA-mediated resistance to Wheat dwarf virus in barley is highly efficient at low temperature | [73] | Artificially transformed | Hordeum vulgare | cultivar Golden Promise | 2015 | Polycistronic artificial miRNA in plasmid vector was successfully transformed into barley embryos and mediated resistance to Wheat dwarf virus. | |||||||
| Global Identification of MicroRNAs and Their Targets in Barley under Salinity Stress | [50] | Hordeum vulgare | cultivar Morex | 2015 | Authors identified 152 miRNAs (142 conserved and 10 novel ones), and 44 miRNAs (39 conserved and 5 novel ones) were found to be salinity-responsive. | ||||||||
| Characterization of microRNAs and their targets in wild barley ( | Hordeum vulgare | subsp. spontaneum) using deep sequencing | [74] | Hordeum vulgare | subsp. | spontaneum | 2016 | A total of 70 known miRNAs and 18 novel miRNA candidates were identified and many of them were predicted to target mRNAs encoding transcription factors. | |||||
| Developmental changes in barley microRNA expression profiles coupled with miRNA target analysis | [75] | Hordeum vulgare | cultivar Rolap | 2016 | miRNA transcriptomes of five barley developmental stages were inspected. Overall, miR168-3p and miR1432-5p levels increased while the 5′U-miR156-5p level decreased during barley development. | ||||||||
| miR393-Mediated Auxin Signaling Regulation is Involved in Root Elongation Inhibition in Response to Toxic Aluminum Stress in Barley | [63] | Hordeum vulgare | cultivar Golden Promise | 2017 | Barley miR393 was functionally characterized. It regulates root sensitivity to aluminum through the alteration of auxin signaling. | ||||||||
| Differential expression of microRNAs and potential targets under drought stress in barley | [55] | Hordeum vulgare | L. cultivars Commander, Fleet, Hindmarsh, and breeding line WI4304 | 2017 | miRNA regulation under drought stress in barley is genotype-specific. | ||||||||
| microRNAs participate in gene expression regulation and phytohormone cross-talk in barley embryo during seed development and germination | [76] | Hordeum vulgare | cultivar Golden Promise | 2017 | A total of 1324 known miRNAs and 448 novel miRNA candidates were identified. miR393-mediated auxin response regulation significantly affected grain development. | ||||||||
| Small RNA Activity in Archeological Barley Shows Novel Germination Inhibition in Response to Environment | [77] | Ancient | Hordeum vulgare | 2017 | Sequencing of miRNAs obtained from archeological barley samples (600–900 years BP) revealed their local adaptation to an agrarian environment around the river Nile. | ||||||||
| Genome-wide analysis of the SPL/miR156 module and its interaction with the AP2/miR172 unit in barley | [78] | Hordeum vulgare | L. | 2018 | The study identified 17 barley | SPL | genes, and 7 of them contain a putative miR156 target site. | ||||||
| Identification of microRNAs in response to aluminum stress in the roots of Tibetan wild barley and cultivated barley | [64] | Hordeum vulgare | Al-sensitive Golden Promise and Tibetan wild barley (Al-tolerant XZ29) | 2018 | 50 miRNAs responsive to aluminum stress were detected, and some of them were found to be exclusively expressed in Al-tolerant XZ29. | ||||||||
| Identification of microRNAs responding to salt stress in barley by high-throughput sequencing and degradome analysis | [53] | Tibetan wild barley accession XZ16; | Hordeum vulgare | cultivar Golden Promise | 2019 | miR393a, miR156d, and miR172b (regulating | HvAFB2/HvTIR1 | , | UGTs | , and | HvAP2 | ) are responsible for salt tolerance in barley roots. | |
| Genotypic difference of cadmium tolerance and the associated microRNAs in wild and cultivated barley | [65] | Hordeum vulgare | cultivar Golden Promise and wild barley WB-1 | 2019 | 216 conserved miRNAs (in 59 miRNA families) and 87 novel miRNAs were identified. Authors suggest that miRNAs may play critical roles underlying the genotypic difference of cadmium tolerance in barley. | ||||||||
| Genome-Wide Identification and Characterization of Drought Stress Responsive microRNAs in Tibetan Wild Barley | [58] | Tibetan wild barley | Hordeum vulgare | L. ssp. Spontaneum | 2020 | 69 conserved miRNAs and 1574 novel miRNAs were identified, some of them were differentially expressed in drought conditions. | |||||||
| Barley microRNAs as metabolic sensors for soil nitrogen availability | [59] | Hordeum vulgare | cultivar Golden Promise | 2020 | Authors identified 13 barley miRNAs that are nitrogen excess responsive with the possible function of metabolic sensors for soil nitrogen availability. | ||||||||
| The Impact of Zinc Oxide Nanoparticles on Cytotoxicity, Genotoxicity, and miRNA Expression in Barley ( | Hordeum vulgare | L.) Seedlings | [79] | Hordeum vulgare | L. var. Abava | 2020 | ZnO nanoparticles significantly changed the expression of barley miR156a, miR159a, and miR159c in a dosage-dependent manner. | ||||||
| Identification of microRNAs in response to low potassium stress in the shoots of Tibetan wild barley and cultivated | [80] | A Tibetan wild barley accession (XZ153) and a cultivar (ZD9) differing in low K tolerance | 2021 | A total of 1088 miRNAs were identified in the two barley genotypes under low potassium conditions. 65 of them were significantly differentially expressed. | |||||||||
| Barley Seeds miRNome Stability during Long-Term Storage and Aging | [81] | Hordeum vulgare | cultivar Damazy | 2021 | miRNome of barley seeds harvested in 1972 was inspected. 61 known and 81 novel miRNA were identified pointing to the fact that miRNAs in dry seeds are extremely stable. | ||||||||
| Identification microRNAs and target genes in Tibetan hulless barley to BLS infection | [82] | Hordeum vulgare | L. variety nudum Hook. f. | 2021 | A total of 36 conserved and 56 novel miRNAs were identified, some of them were differentially expressed between BLS (barley leaf stripe fungal disease)-sensitive and BLS-tolerant barley genotypes. | ||||||||
| Pi-starvation induced transcriptional changes in barley revealed by a comprehensive RNA-Seq and degradome analyses | [62] | Hordeum vulgare | L. | 2021 | Authors suggest that barley adapts to inorganic phosphate (Pi)-starvation also via differential expression of several miRNAs. | ||||||||
| Identification of microRNAs Responding to Aluminium, Cadmium and Salt Stresses in Barley Roots | [51] | Hordeum vulgare | cultivar Golden Promise | 2021 | 525 miRNAs (198 known and 327 novel miRNAs) were identified through high-throughput sequencing. 31 miRNAs were differentially expressed under inspected stresses. | ||||||||
| An miR156-regulated nucleobase-ascorbate transporter 2 confers cadmium tolerance via enhanced anti-oxidative capacity in barley | [83] | Hordeum vulgare | genotypes Zhenong8 (ZN8) (Cd-tolerant genotype) and W6nk2 (Cd-sensitive genotype) | 2022 | miR156g-3p_3 targets a novel nucleobase-ascorbate transporter gene ( | HvNAT2 | ). | HvNAT2 | evolved from the | Zygnematales | in | Streptophyte algae | and positively regulates cadmium tolerance → genetic engineering of NAT in plants may have potential in the remediation of soil/water cadmium pollution |
| Regulation of Phenolic Compound Production by Light Varying in Spectral Quality and Total Irradiance | [68] | Hordeum vulgare | L. cultivar Bojos | 2022 | Several barley miRNAs were differentially expressed in response to the spectral quality of incident light. |
