MdBRC1 and MdFT2 Interaction Fine-Tunes Bud Break Regulation in Apple
Authors: Gioppato, H. A., Estevan, J., Al Bolbol, M., Soriano, A., Garighan, J., Jeong, K., Georget, C., Soto, D. G., El Khoury, S., Falavigna, V. d. S., George, S., Perales, M., Andres, F.
The study identifies the transcription factor MdBRC1 as a key inhibitor of bud growth during the ecodormancy phase in apple (Malus domestica), directly regulating dormancy‑associated genes and interacting with the flowering promoter MdFT2 to modulate bud break. Comparative transcriptomic analysis and gain‑of‑function experiments in poplar demonstrate that MdFT2 physically binds MdBRC1, attenuating its repressive activity and acting as a molecular switch for the transition to active growth.
The study introduced full-length SOC1 genes from maize and soybean, and a partial SOC1 gene from blueberry, into tomato plants under constitutive promoters. While VcSOC1K and ZmSOC1 accelerated flowering, all three transgenes increased fruit number per plant mainly by promoting branching, and transcriptomic profiling revealed alterations in flowering, growth, and stress‑response pathways.
The study applied Spatial Analysis of Field Trials with Splines (SpATS) and Neighbor Genome-Wide Association Study (Neighbor GWAS) to barley field data, revealing that neighboring genotypes contribute to spatial variation in disease damage. Neighbor GWAS identified variants on chromosome 7H that modestly affect net form net blotch and scald resistance, suggesting that genotype mixtures could mitigate pest damage.
The study evaluated natural genetic variation in non-photochemical quenching and photoprotection across 861 sorghum accessions grown in the field over two years, revealing moderate to high broad-sense heritability for chlorophyll fluorescence traits. By integrating genome-wide association studies (GWAS) with transcriptome-wide association studies (TWAS) and covariance analyses, the authors identified 110 high-confidence candidate genes underlying photoprotection, highlighting a complex, polygenic architecture for these traits.
The study used comparative transcriptomics across Erysimum species to identify two 2‑oxoglutarate‑dependent dioxygenases, CARD5 and CARD6, responsible for the 14β‑ and 21‑hydroxylation steps in cardenolide biosynthesis in Erysimum cheiranthoides. Knockout mutants lacking these genes accumulated pathway intermediates, and transient expression in Nicotiana benthamiana confirmed their enzymatic functions, while structural modeling pinpointed residues linked to neofunctionalization.
Ethylene and ROS Signaling Are Key Regulators of Lateral Root Development under Salt Stress in Tomato
Authors: Rahmati Ishka, M., Zhao, J., Sussman, H., Mohanty, D., Craft, E., Yu, L., Pineros, M., Tester, M., Kawa, D., Mittler, R., Nelson, A., Fei, Z., Julkowska, M. M.
The study examined salt-induced alterations in root system architecture across a diverse panel of wild and cultivated tomato accessions, identifying tolerant varieties with distinct lateral root strategies. By combining Bulk Segregant Analysis of an F2 population with GWAS, the authors pinpointed 22 candidate genes, further narrowing to two key regulators through RNA‑Seq and functional assays involving ethylene and ROS profiling. These findings reveal genetic targets for improving salt resilience in tomato root development.
Comparative transcriptomics uncovers plant and fungal genetic determinants of mycorrhizal compatibility
Authors: Marques-Galvez, J. E., de Freitas Pereira, M., Nehls, U., Ruytinx, J., Barry, K., Peter, M., Martin, F., Grigoriev, I. V., Veneault-Fourrey, C., Kohler, A.
The study used comparative and de‑novo transcriptomic analyses in poplar to uncover plant and fungal gene regulons that govern ectomycorrhizal (ECM) compatibility, distinguishing general fungal‑sensing responses from ECM‑specific pathways. Key findings include modulation of jasmonic acid‑related defenses, coordinated regulation of secretory and cell‑wall remodeling genes, and dynamic expression of the Common Symbiosis Pathway during early and mature symbiosis stages.
High radiosensitivity in the conifer Norway spruce (Picea abies) due to lesscomprehensive mobilisation of protection and repair responses compared to the radiotolerant Arabidopsis thaliana
Authors: Bhattacharjee, P., Blagojevic, D., Lee, Y., Gillard, G. B., Gronvold, L., Hvidsten, T. R., Sandve, S. R., Lind, O. C., Salbu, B., Brede, D. A., Olsen, J. E.
The study compared early protective, repair, and stress responses to chronic gamma irradiation in the radiosensitive conifer Norway spruce (Picea abies) and the radiotolerant Arabidopsis thaliana. Norway spruce exhibited growth inhibition, mitochondrial damage, and higher DNA damage at low dose rates, while Arabidopsis maintained growth, showed minimal organelle damage, and activated DNA repair and antioxidant genes even at the lowest dose rates. Transcriptomic analysis revealed that the tolerant species mounts a robust transcriptional response at low doses, whereas the sensitive species only responds at much higher doses.
The study used comparative transcriptomics to examine how Fusarium oxysporum isolates with different lifestyles on angiosperms regulate effector genes during infection of the non‑vascular liverwort Marchantia polymorpha. Core effector genes on fast core chromosomes are actively expressed in the bryophyte host, while lineage‑specific effectors linked to angiosperm pathogenicity are silent, and disruption of a compatibility‑associated core effector alters the expression of other core effectors, highlighting conserved fungal gene networks across plant lineages.
The study examined how genetic variation among 181 wheat (Triticum aestivum) lines influences root endophytic fungal communities using ITS2 metabarcoding. Heritability estimates and GWAS identified 11 QTLs linked to fungal clade composition, highlighting genetic control of mycobiota, especially for biotrophic AMF. These findings suggest breeding can be used to modulate beneficial root-fungal associations.