Genetius

The study examined how DNA methylation influences cold stress priming in Arabidopsis thaliana, revealing that primed plants exhibit distinct gene expression and methylation patterns compared to non-primed plants. DNA methylation mutants, especially met1 lacking CG methylation, showed altered cold memory and misregulation of the CBF gene cluster, indicating that methylation ensures transcriptional precision during stress recall.

The study examined DNA methylation dynamics in Arabidopsis thaliana shoots and roots under heat, phosphate deficiency, and combined stress using whole-genome bisulfite sequencing, small RNA‑seq, and RNA‑seq. Distinct stress‑specific methylation patterns were identified, with heat and combined stress causing CHH hypomethylation, phosphate deficiency causing hyper‑ and hypomethylation in shoots and roots respectively, and the combined stress exhibiting a unique signature independent of additive effects. Methylation changes were concentrated in transposable elements and regulatory regions, implicating RdDM and CMT2 pathways and suggesting a role in chromatin accessibility rather than direct transcriptional control.

The study examines how ectopic accumulation of methionine in Arabidopsis thaliana leaves, driven by a deregulated AtCGS transgene under a seed‑specific promoter, reshapes metabolism, gene expression, and DNA methylation. High‑methionine lines exhibit increased amino acids and sugars, activation of stress‑hormone pathways, and reduced expression of DNA methyltransferases, while low‑methionine lines show heightened non‑CG methylation without major transcriptional changes. Integrated transcriptomic and methylomic analyses reveal a feedback loop linking sulfur‑carbon metabolism, stress adaptation, and epigenetic regulation.

The study integrated 16 Arabidopsis thaliana whole‑genome bisulfite sequencing datasets from 13 stress experiments using a unified bioinformatic pipeline to map common and stress‑specific DNA methylation changes. Differentially methylated regions varied by stress type and methylation context, with CG DMRs enriched in gene bodies and CHG/CHH DMRs in transposable elements, some of which overlapped loci prone to stable epimutations. Gene ontology and TE enrichment analyses highlighted shared stress pathways and suggest environmental stress can generate heritable epigenetic variation.

The study uses genome-wide association mapping in Arabidopsis thaliana to identify CDCA7 as a trans‑regulator of CG DNA methylation (mCG) that interacts with the chromatin remodeler DDM1. CDCA7 selectively modulates mCG levels and transposable‑element silencing, with natural allelic variation correlated with geographic distribution and local adaptation.

The study demonstrates that the chromatin remodeler DDM1 is essential for biomass heterosis in Arabidopsis thaliana hybrids, as its loss leads to reduced rosette diameter, extensive DNA hypomethylation, and transcriptomic imbalances, including up‑regulation of xyloglucan transferase genes and down‑regulation of circadian‑rhythm genes. Salicylic acid levels were found not to correlate with heterosis, indicating a SA‑independent mechanism. Maintaining parental DNA‑methylation divergence via DDM1 thus underpins heterotic vigor, and disruption of DDM1 compromises this epigenetic complementarity.

The study identifies GyrB3 as a novel nuclear protein that partners with histone deacetylases to modulate DNA methylation and H3 acetylation at transposable elements, thereby influencing TE silencing. Loss‑of‑function gyrb3 mutations suppress the DNA hypermethylation and developmental defects of IBM1‑deficient plants, highlighting GyrB3’s role in preserving epigenomic stability in plants.

The study combined long‑read whole‑genome assembly, multi‑omics profiling (DNA methylation, mRNA, ribosome‑associated transcripts, tRNA abundance, and protein levels) in two Arabidopsis thaliana accessions to evaluate how genomic information propagates through the Central Dogma. Codon usage in gene sequences emerged as the strongest predictor of both mRNA and protein abundance, while methylation, tRNA levels, and ribosome‑associated transcripts contributed little additional information under stable conditions.

The study reveals that a set of REPRODUCTIVE MERISTEM (REM) transcription factors, termed RIMs, are essential for directing RNA‑directed DNA methylation (RdDM) to CLSY3 targets in a sex‑specific manner in Arabidopsis reproductive tissues. Disruption of RIM DNA‑binding domains or their target motifs abolishes RdDM at these loci, demonstrating that genetic cues can guide de novo methylation patterns.

The study identifies four Arabidopsis REM transcription factors (VDD, VAL, REM12, REM13) that bind specific DNA sequences and, together with GDE1, recruit RNA polymerase IV to produce 24‑nt siRNAs that direct DNA methylation at designated loci. Loss of GDE1 causes Pol IV complexes to relocalize to sites bound by REM8, indicating that REM proteins provide sequence‑specific cues for epigenetic patterning.