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 engineered Tobacco rattle virus vectors incorporating distinct RNA secondary structures as mobility factors to improve guide RNA delivery to plant meristems. Using Nicotiana benthamiana plants expressing Cas9, optimal virus constructs were identified that generated both somatic and heritable edits, and these constructs were successfully applied to edit the emerging oilseed crop pennycress (Thlaspi arvense).
The authors introduce the ENABLE(R) Gene Editing in planta toolkit, a streamlined two‑step cloning system for creating CRISPR/Cas9 knockout vectors suitable for transient or stable transformation. Validation was performed in Oryza sativa protoplasts and Arabidopsis thaliana plants, and the toolkit includes low‑cost protocols aimed at facilitating adoption in the Global South.
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 mapped the cis‑regulatory landscape of the winter rapeseed cultivar Express617, identifying thousands of novel regulatory elements and characterizing super‑enhancers that are asymmetrically enriched in the Cn subgenome of Brassica napus. An in‑silico pipeline combining population‑level expression data and machine‑learning models revealed that many SE‑associated genes are expressed above predicted levels, and structural variants disrupting SEs lead to reduced gene expression, highlighting their functional importance for gene regulation and breeding.
The authors created a fast‑cycling, isogenic barley line (GP‑rapid) by introgressing the wild‑type Ppd‑H1 allele from Igri into the Golden Promise cultivar and performing two backcrosses to limit the donor genome, achieving a 25% reduction in generation time under speed‑breeding conditions while retaining high transformation efficiency. CRISPR/Cas9‑mediated editing of Ppd‑H1 showed regeneration and transformation rates comparable to the original Golden Promise, establishing GP‑rapid as a rapid platform for transgenic and gene‑edited barley research.
The study applied CRISPR/Cas9 gene editing to Physalis peruviana to modify plant‑architecture genes and create a compact growth ideotype. This compact phenotype is intended to increase per‑plot yield and support future breeding efforts for this nutritionally valuable minor crop.
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.
Drought-Induced Epigenetic Memory in the cambium of Poplar Trees persists and primes future stress responses
Authors: DUPLAN, A., FENG, Y. Q., LASKAR, G., CAI, B. D., SEGURA, V., DELAUNAY, A., LE JAN, I., DAVIAUD, C., TOUMI, A., LAURANS, F., SOW, M. D., ROGIER, O., POURSAT, P., DURUFLE, H., JORGE, V., SANCHEZ, L., COCHARD, H., ALLONA, I., TOST, J., FICHOT, R., MAURY, S.
The study examined short‑term and transannual drought memory in cambium tissues of two Populus genotypes and four epitypes with modified DNA‑methylation machinery, revealing persistent hormone, transcript, and methylation changes one week after stress relief. Trees previously stressed in Year 1 displayed distinct physiological and molecular responses to a second drought in Year 2, indicating long‑term memory linked to stable CG‑context DNA methylation, with genotype‑dependent differences in plasticity and stability. These findings position the cambium as a reservoir for epigenetic stress memory and suggest exploitable epigenetic variation for tree breeding under drought.
The study used CRISPR/Cas9 to edit the downstream region of the Arabidopsis thaliana FLOWERING LOCUS T (FT) gene, identifying a 2.3‑kb segment containing the Block E enhancer as crucial for normal FT expression and flowering. Fine‑scale deletions pinpointed a 63‑bp core module with CCAAT‑ and G‑boxes, and revealed a cryptic CCAAT‑box that becomes active when repositioned, highlighting the importance of local chromatin context and motif arrangement for enhancer function.