The interplay between autophagy and the carbon/nitrogen ratio as key modulator of the auxin-dependent chloronema-caulonema developmental transition in Physcomitrium patens.
Authors: Pettinari, G., Liberatore, F., Mary, V., Theumer, M., Lascano, R., Saavedra, L. L.
Using the bryophyte Physcomitrium patens, the study shows that loss of autophagy enhances auxin‑driven caulonemata differentiation and colony expansion under low nitrogen or imbalanced carbon/nitrogen conditions, accompanied by higher internal IAA, reduced PpPINA expression, and up‑regulated RSL transcription factors. Autophagy appears to suppress auxin‑induced differentiation during nutrient stress, acting as a hub that balances metabolic cues with hormonal signaling.
The study examined how dual‑purpose hemp (Cannabis sativa) adjusts to different phosphate levels, showing that flower biomass is maintained unless phosphate is completely removed. Integrated physiological measurements and transcriptomic profiling revealed that phosphate is reallocated to flowers via glycolytic bypasses and organic phosphate release, while key regulatory genes followed expected patterns but did not suppress uptake at high phosphate, leading to nitrate depletion that limits growth.
The abstract proposes that microbial indole-3-acetic acid (IAA) enhances plant thermotolerance by regulating proline metabolism, coordinating early osmoprotective synthesis with later catabolism to support growth and redox balance during heat stress. This regulation is hypothesized to involve integration of auxin perception (HSP90‑TIR1), MAPK signaling (MPK‑IAA8), mitochondrial redox components (SSR1, HSCA2) and interactions with abscisic acid and ethylene, offering a framework for using auxin‑producing microbes to boost heat resilience.
The study identifies MtFTb1 and MtFTb2 as essential, redundant regulators of long‑day flowering in the legume Medicago truncatula, demonstrating that they are required for up‑regulating MtFTa1 under vernalised long‑day conditions. Using CRISPR/Cas9‑generated single and double mutants, the authors show that double mutants are specifically delayed in flowering under long days while retaining vernalization responsiveness, and transcriptomic analyses reveal that MtFTb1/2 activate MADS‑box genes and other flowering regulators.
Using ten Phaeodactylum tricornutum mutant strains with graded constitutive Lhcx1 expression, the study links NPQ induction under high light to physiological outcomes (oxidized QA, increased cyclic electron flow) and extensive transcriptomic reprogramming, affecting nearly half the genome. The approach demonstrates that higher NPQ mitigates PSII damage, boosts ATP production for repair, and drives distinct gene regulatory networks, providing a model framework for dissecting photosynthetic and gene expression integration.
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.
Using a forward genetic screen of 284 Arabidopsis thaliana accessions, the study identified extensive natural variation in root endodermal suberin and pinpointed the previously unknown gene SUBER GENE1 (SBG1) as a key regulator. GWAS and protein interaction analyses revealed that SBG1 controls suberin deposition by binding type‑one protein phosphatases (TOPPs), with disruption of this interaction or TOPP loss‑of‑function altering suberin levels, linking the pathway to ABA signaling.
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 presents an optimized Agrobacterium-mediated transformation toolkit for Sorghum bicolor that achieves up to 95.7% editing efficiency using CRISPR/Cas9 targeting the SbPDS gene, and demonstrates comparable performance with a PAM‑broadened SpRY variant. This platform enables multiplex genome editing and is positioned for integration of advanced tools such as prime and base editors to accelerate sorghum breeding.
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.