Hordeum vulgare

In this study, HMs underwent purifying selection based on Ka/Ks ratios. Gene/genome duplications impacted HM evolution in wheat. TaHM expression changed during grain development under brassinosteroid, brassinazole, or activated charcoal treatments. ZmHMs responded to gibberellin and drought. TaHMs function in grain development, BR-/brassinazole-mediated root growth, activated charcoal-mediated root/leaf growth, and biotic/abiotic adaptations. ZmHMs function in seed development, GA-mediated leaf growth, and drought adaptation.

Hordeum vulgare

Microspore embryogenesis involves epigenetic reprogramming, particularly histone H3K9 methylation dynamics. In Brassica napus and Hordeum vulgare, low H3K9 methylation promotes cell reprogramming and embryogenesis initiation. As embryogenesis progresses, H3K9 methylation increases, correlating with BnHKMT SUVR4-like and BnLSD1-like expression. Short-term BIX-01294 treatment enhances reprogramming and reduces H3K9 and DNA methylation, while long-term treatment inhibits embryo differentiation, indicating H3K9 methylation is essential for differentiation. Pharmacological modulation of histone methylation via BIX-01294 may improve microspore embryogenesis efficiency.

Hordeum vulgare

Epigenetic modifications during plant development are established by positional information and tissue specificity, determining cell fate and differentiation. The root apical meristem (RAM), generating radial tissue patterns, models the correlation between cell position and epigenetic modification patterns. Levels of histone and DNA modifications vary across RAM tissues. Crucially, histone H4 acetylation in the epidermis is not solely replication-dependent and likely functions in epidermal cell differentiation.

Hordeum vulgare

Drought triggers ABA-mediated gene expression reprogramming in barley (Hordeum vulgare cv. Morex). Epigenome analysis identified 129 genes gaining H3K4me3 and 2008 genes gaining H3K9ac under drought, indicating H3K9ac responds more sensitively than H3K4me3. Genes marked with these euchromatic modifications and induced by drought are predominantly involved in ABA signaling and related pathways. This includes two PP2C family members, key regulators of ABA signaling.

Hordeum vulgare

Multi-omics analysis of eight hulless barley varieties under abiotic stress identified 231,440 lowly methylated regions (LMRs), predominantly in intergenic regions. Correlation analysis revealed 97,909 enhancer-gene pairs. Transcription factor regulatory network inference for drought stress predicted the NAC transcription factor targets TCP, bHLH, and bZIP transcription factor genes. H3K27me3 modification regions overlapped with LMRs more than H3K4me3 regions. Single nucleotide polymorphism variation was more abundant in LMRs than in other genomic regions. Epigenetic regulation, involving DNA methylation and histone modifications, underpins hulless barley's adaptation to abiotic stress, with transcription factors like NAC playing significant roles.

Hordeum vulgare

WHIRLY1 overexpression in barley delayed drought-induced leaf senescence and suppressed drought-induced increases in ABA concentration and ABA-dependent marker genes HvNCED1 and HvS40. RNAseq revealed that WHIRLY1 overexpression prevented drought-induced upregulation of stress- and ABA-related genes but promoted genes related to primary metabolism and growth, indicating WHIRLY1 balances stress response and developmental pathways. Crucially, WHIRLY1 overexpression decreased levels of euchromatic marks H3K4me3 and H3K9ac at the HvNCED1 and HvS40 promoters and transcriptional start sites. This demonstrates that WHIRLY1, acting as a retrograde signal, modulates ABA-related nuclear gene expression reprogramming during drought via differential histone modifications.

Hordeum vulgare

Analysis identified 117 barley genes involved in DNA methylation, histone modification, and chromatin remodeling. RNAseq revealed distinct gene expression profiles during dark-induced leaf senescence (DILS) compared to developmental leaf senescence (DLS) and controls. Western blot showed increased H3K4me3 and H3K9me2 methylation during both DILS and DLS. H3K9ac acetylation decreased significantly during DILS but remained unchanged during DLS. These findings indicate different epigenetic regulation of senescence types and suggest an epigenetically regulated molecular switch between cell survival and death in DILS.

Hordeum vulgare

ChIP-seq mapping of nine histone modifications in barley seedlings defined four modification classes and ten chromatin states. Five states map to genes and five to intergenic regions. H3K36me3-associated genic states correlate with constitutive expression, while an H3K27me3-containing genic state associates with differential expression. Chromosomes comprise three global environments: telomere-proximal regions feature high H3K27me3 density covering genes and intergenic DNA with low H3K27me1; gene-rich interior regions show active chromatin states, decreased H3K27me3, and increased H3K27me1/H3K9me2; pericentromeric regions contain H3K27me3-depleted retrotransposon-rich areas marked by abundant H3K27me1 and H3K9me2. Intergenic H3K27me3 specifies facultative heterochromatin in telomere-proximal regions, while H3K27me1 marks constitutive heterochromatin elsewhere.