Hordeum vulgare

This study demonstrates that DNA methylation and histone modifications enable barley adaptation to temperature stress. Methylation-sensitive amplification polymorphism analysis revealed that mild low temperature (14°C) induced more DNA methylation, while high temperature (38°C) promoted more DNA demethylation compared to control (22°C). HT stress significantly elevated H3K9ac and H3K4me3 levels versus MLT, leading to chromatin loosening and gene expression activation. Transcriptome analysis showed more differentially expressed genes (DEGs) under HT than MLT. This study reveals epigenetic regulatory mechanisms underlying temperature stress responses in barley.

Hordeum vulgare

This study investigated spatial distribution of epigenetic modifications in Hordeum vulgare root apical meristem using immunostaining. Tissue-specific patterns of H4K5ac, H3K4me2, H3K9me2, and DNA methylation (5mC) were established. The lateral root cap showed highest H3K9me2 and 5mC levels. Epidermis nuclei at the proximal meristem-elongation zone boundary exhibited peak 5mC and H3K9me2. Vascular tissues displayed maximal H4K5ac. Cytoplasmic histone modifications occurred tissue-specifically. This immunolocalization provides topographic context for epigenetic markers during root development.

Hordeum vulgare

This study identified two barley Type I-like MADS-box genes showing DNA methylation differences in their upstream and downstream regulatory regions during different seed developmental stages and after exogenous ABA application. These methylation variations are suggestive of epigenetic regulation of gene expression.

Hordeum vulgare

High-resolution detection of phosphorylated histone H3 at serine 10 in mitotic barley chromosomes for scanning electron microscopy was shown using a novel application of indirect immunogold labeling with Nanogold. This method permits localization and quantification of signals in a three-dimensional context. Because the chromosome structure is well preserved, characterization of binding sites (chromomeres, parallel matrix fibers, solenoids), currently in the realm of nanometer decades, is possible. Quantification and three-dimensional localization of labels is possible with stereoscopic analysis. Limitations of the method pertain to the challenges in preservation of chromosome ultrastructure, accessibility of immunoreactants into the fixed chromatin and unspecific labeling. The differences between silver and gold enhancement and the current status of labeling efficiency are addressed.

Hordeum vulgare

Histone H3 phosphorylation at threonine 3 (H3T3ph) and threonine 32 (H3T32ph) exhibits conserved spatiotemporal patterns during mitosis and meiosis. In large-genome species (Secale cereale, Vicia faba, Hordeum vulgare), phosphorylation initiates at prophase (mitosis) and diakinesis (meiosis I), with dephosphorylation in late anaphase. Arabidopsis thaliana (small genome) shows earlier dephosphorylation at anaphase. During metaphase (mitosis) and metaphase I, both modifications distribute along entire chromosomes. In meiosis II, H3T3ph localizes strictly to pericentromeric domains, while H3T32ph occurs along chromosome arms across all species.

Hordeum vulgare

Epigenetic processes are highly dynamic during barley endosperm development. The repressive H3K27me3 modification is globally reduced in endosperm tissues and at specific genes regulating development and storage compounds.

Hordeum vulgare

During barley pollen development, vegetative and generative nuclei initially share identical chromatin modifications. Differential patterns emerge with nuclear differentiation. H3K27me3 enriches in subtelomeric euchromatin and becomes restricted to the vegetative nucleus, indicating a role in gene activation. Cytoplasmic H3K9ac in the generative cell suggests unknown functions.

Hordeum vulgare

HMT and HDM originate from Chromista and are highly conserved in green plants. Histone methylation modifications became complex and diverse during plant evolution, aiding adaptation to variable environments. In barley, HMT/HDM families show high conservation but differential variation in the Lasa Goumang SDG subfamily. HvHMTs/HvHDMs exhibit tissue-specific expression and complex patterns under multiple stresses. HMT/HDM amplification facilitates plant environmental adaptation while remaining conserved in barley development and stress responses.