DECREASE IN DNA METHYLATION 1-mediated epigenetic regulation maintains gene expression balance required for heterosis in Arabidopsis thaliana
Authors: Matsuo, K., Wu, R., Yonechi, H., Murakami, T., Takahashi, S., Kamio, A., Akter, M. A., Kamiya, Y., Nishimura, K., Matsuura, T., Tonosaki, K., Shimizu, M., Ikeda, Y., Kobayashi, H., Seki, M., Dennis, E. S., Fujimoto, R.
The study demonstrates that the chromatin remodeler DDM1 is essential for biomass heterosis in Arabidopsis thaliana hybrids, as loss of DDM1 function leads to reduced rosette growth and extensive genotype‑specific transcriptomic and DNA methylation changes. Whole‑genome bisulfite sequencing revealed widespread hypomethylation in ddm1 mutants, while salicylic acid levels were found unrelated to heterosis, indicating that epigenetic divergence, rather than SA signaling, underpins hybrid vigor.
The study examined how soil phosphorus and nitrogen availability influence wheat root-associated arbuscular mycorrhizal fungal (AMF) communities and the expression of mycorrhizal nutrient transporters. Field sampling across two years combined with controlled pot experiments showed that P and N jointly affect AMF colonisation, community composition (with Funneliformis dominance under high P), and regulation of phosphate, ammonium, and nitrate transporters. Integrating metabarcoding and RT‑qPCR provides a framework to assess AMF contributions to crop nutrition.
The study compared aphid resistance and Barley Yellow Dwarf Virus (BYDV) transmission among three wheat varieties (G1, RGT Wolverine, RGT Illustrious). G1 emits the repellent 2‑tridecanone, restricts aphid phloem access, and shows reduced BYDV transmission, whereas RGT Wolverine limits systemic viral infection despite high transmission efficiency. The authors suggest breeding the two resistance mechanisms together for improved protection.
The study investigated whether wheat homoeologous genes actively compensate for each other when one copy acquires a premature termination codon (PTC) mutation. By analyzing mutagenised wheat lines, the authors found that only about 3% of cases exhibited upregulation of the unaffected homoeolog, indicating that widespread active transcriptional compensation is absent in wheat.
Overexpression of the wheat bHLH transcription factor TaPGS1 leads to increased flavonol accumulation in the seed coat, which disrupts polar auxin transport and causes localized auxin accumulation, delaying endosperm cellularization and increasing cell number, thereby enlarging grain size. Integrated metabolomic and transcriptomic analyses identified upregulated flavonol biosynthetic genes, revealing a regulatory module that links flavonol-mediated auxin distribution to seed development in wheat.
The study evaluated how alginate oligosaccharide (AOS) chain length influences the levels of seven key phytohormones in wheat seedlings challenged with Botrytis cinerea. Hormone profiling revealed that mid‑range oligomers (DP 4‑6) most strongly up‑regulate defense‑related hormones (JA, SA, ABA, CTK), whereas longer oligomers (DP 7) most effectively suppress ethylene. These findings suggest that tailoring AOS polymerization can optimize disease resistance and growth in cereal crops.
The study shows that the SnRK1 catalytic subunit KIN10 directs tissue-specific growth‑defense programs in Arabidopsis thaliana by reshaping transcriptomes. kin10 knockout mutants exhibit altered root transcription, reduced root growth, and weakened defense against Pseudomonas syringae, whereas KIN10 overexpression activates shoot defense pathways, increasing ROS and salicylic acid signaling at the cost of growth.
The study investigates the altered timing of the core circadian oscillator gene ELF3 in wheat compared to Arabidopsis, revealing that dawn-specific expression in wheat arises from repression by TOC1. An optimized computational model integrating experimental expression data and promoter architecture predicts that wheat’s circadian oscillator remains robust despite this shift, indicating flexibility in plant circadian network design.
The Global Wheat Full Semantic Organ Segmentation (GWFSS) dataset
Authors: Wang, Z., Zenkl, R., Greche, L., De Solan, B., Bernigaud Samatan, L., Ouahid, S., Visioni, A., Robles-Zazueta, C. A., Pinto, F., Perez-Olivera, I., Reynolds, M. P., Zhu, C., Liu, S., D'argaignon, M.-P., Lopez-Lozano, R., Weiss, M., Marzougui, A., Roth, L., Dandrifosse, S., Carlier, A., Dumont, B., Mercatoris, B., Fernandez, J., Chapman, S., Najafian, K., Stavness, I., Wang, H., Guo, W., Virlet, N., Hawkesford, M., Chen, Z., David, E., Gillet, J., Irfan, K., Comar, A., Hund, A.
The Global Wheat Dataset Consortium released a comprehensive semantic segmentation dataset (GWFSS) of wheat organs across developmental stages, comprising 1,096 fully annotated images and 52,078 unannotated images from 11 institutions. Models based on DeepLabV3Plus and Segformer were trained, with Segformer achieving ≈90% mIoU for leaves and spikes but lower precision (54%) for stems, while also enabling weed exclusion and discrimination of necrotic, senescent, and residue tissues.
RNA‑seq of 328 wheat lines using a pan‑genome reference uncovered over 20,000 additional transcripts beyond the Chinese Spring genome and enabled construction of a pan‑gene eQTL regulatory atlas. Multi‑omics integration identified 231 high‑confidence candidate genes influencing 34 agronomic traits and powdery mildew resistance, with functional validation showing 80% of candidates affecting trait phenotypes via an EMS mutant library.