The study establishes a tractable system using the large bloom-forming diatom Coscinodiscus granii and its natural oomycete parasite Lagenisma coscinodisci, enabling manual isolation of single host cells and stable co-cultures. High‑quality transcriptomes for both partners were assembled, revealing diverse oomycete effectors and a host transcriptional response involving proteases and exosome pathways, while also profiling the co‑occurring heterotrophic flagellate Pteridomonas sp. This tripartite platform provides a unique marine model for dissecting molecular mechanisms of oomycete‑diatom interactions.
Root growth promotion by Penicillium melinii: mechanistic insights and agricultural applications
Authors: Gutierrez-Manso, L., Devesa-Aranguren, I., Conesa, C. M., Monteoliva-Garcia, G., Gonzalez-Sayer, S., Lozano-Enguita, A., Blasio, F., Ugena, L., Nolasco, J., Vazquez-Mora, A., Levy, C. C. B., Ariel Otero, E., Fernandez-Calvo, P., Moreno-Risueno, M. A., petrik, I., Pencik, A., Reguera, M., Gonzalez-Bodi, S., Huerta-Cepas, J., Sacristan, S., del Pozo, J. C., Cabrera, J.
The study characterizes the endophytic fungus Penicillium melinii, isolated from Arabidopsis thaliana roots, as a plant‑growth‑promoting agent that enhances root architecture and biomass across Arabidopsis, quinoa, and tomato. Integrated phenotypic, transcriptomic, and hormonal analyses reveal that the fungus stimulates auxin‑related pathways and modest stress responses, leading to increased tomato yield in field trials, underscoring its value as a model for root development and a sustainable biostimulant.
The study used paired whole‑genome bisulphite sequencing and RNA‑seq on wheat landraces to investigate how DNA methylation patterns change during drought stress, revealing antagonistic trends across cytosine contexts and a key demethylation role for ROS1a family members. Gene‑body methylation correlated positively with expression but negatively with stress‑responsive changes, while drought‑induced hyper‑methylation of specific transposable elements, especially the RLX_famc9 LTR retrotransposon, appears to modulate downstream gene regulation via siRNA precursors.
The study demonstrates that salinity stress induces a photomorphogenic‑like response in dark‑grown Arabidopsis thaliana seedlings, resulting in reduced apical hook curvature and impaired soil emergence. This phenotype is linked to disrupted asymmetric epidermal cell elongation, decreased auxin signaling and PIN3 abundance on the hook’s concave side, repression of BBX28 expression, and loss of a spatial COP1 gradient, highlighting spatial regulation as a key factor in stress‑affected seedling development.
SPOROCYTELESS/NOZZLE acts together with MADS-domain transcription factors to regulate an auxin-dependent network controlling the Megaspore Mother Cell development
Authors: Cavalleri, A., Astori, C., Manrique, S., Bruzzaniti, G., Smaczniak, C., Mizzotti, C., Ruiu, A., Spano, M., Movilli, A., Gregis, V., Xu, X., Kaufmann, K., Colombo, L.
The study elucidates the SPL/NZZ‑dependent regulatory pathway governing megaspore mother cell (MMC) differentiation, revealing that SPL/NZZ directly targets genes and interacts with ovule‑identity MADS‑domain transcription factor complexes. Integration of multi‑omics data with genetic complementation and mutant analyses uncovers an auxin‑dependent downstream network that drives MMC formation.
The study evaluated a transgenic soybean line (VPZ-34A) expressing Arabidopsis VDE, PsbS, and ZEP for combined improvements in light‑use efficiency and carbon assimilation under ambient and elevated CO2 in a FACE experiment. While VPZ‑34A showed enhanced maximum quantum efficiency of PSII under fluctuating light, it did not increase carbon assimilation efficiency or yield, and transcriptome analysis revealed limited gene expression changes. The results suggest that VPZ‑mediated photosynthetic gains are insufficient to boost productivity under elevated CO2.
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 demonstrates that very long chain sphingolipids in the outer membrane leaflet interdigitate with inner‑leaflet phosphatidylserine, forming a vertical bridge that organizes PS nanodomains and enables auxin‑induced activation of the Rho‑GTPase ROP6. Disruption of sphingolipid biosynthesis disperses these nanodomains, impairing ROP6 signaling, cytoskeletal dynamics, and directional growth, highlighting interleaflet coupling as a key mechanism linking membrane asymmetry to plant signal transduction.
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.