The study investigates the role of two ATP-binding cassette transporters, MpABCG1 and MpABCG36, in the sequestration of specialized metabolites within oil bodies of the liverwort Marchantia polymorpha. Loss‑of‑function mutants displayed reduced accumulation of sesquiterpenes and, specifically for MpABCG1, decreased levels of bis‑bibenzyls, while oil‑body formation remained largely unaffected, indicating these transporters are essential for metabolite accumulation rather than organelle biogenesis.
Phylogenomic challenges in polyploid-rich lineages: Insights from paralog processing and reticulation methods using the complex genus Packera (Asteraceae: Senecioneae)
Authors: Moore-Pollard, E. R., Ellestad, P., Mandel, J.
The study examined how polyploidy, hybridization, and incomplete lineage sorting affect phylogenetic reconstructions in the genus Packera, evaluating several published paralog‑processing pipelines. Results showed that the choice of orthology and paralog handling methods markedly altered tree topology, time‑calibrated phylogenies, biogeographic histories, and detection of ancient reticulation, underscoring the need for careful methodological selection alongside comprehensive taxon sampling.
The study demonstrates that limonene, a natural essential‑oil component, strongly inhibits Fusarium oxysporum, the causal agent of potato dry rot, by impairing colony growth, hyphal morphology, spore viability, membrane integrity, and transcription/translation processes, as well as disrupting ion homeostasis. Combined treatments reveal additive effects with mancozeb and synergistic effects with hymexazol, highlighting limonene's potential as an eco‑friendly bio‑fungicide for potato disease management.
The study characterizes the single-copy S-nitrosoglutathione reductase 1 (MpGSNOR1) in the liverwort Marchantia polymorpha, showing that loss-of-function mutants generated via CRISPR/Cas9 exhibit marked morphological defects and compromised SNO homeostasis and immune responses. These findings indicate that GSNOR-mediated regulation of S‑nitrosylation is an ancient mechanism linking development and immunity in early land plants.
The study examines how proteasomal degradation of A‑class and B‑class Auxin Response Factors (ARFs) is regulated in the bryophyte Marchantia polymorpha, identifying a key residue required for MpARF2 degradation that is also conserved in MpARF1. While disruption of MpARF2 degradation impairs development across life‑cycle stages, blocking MpARF1 degradation has minimal phenotypic impact, indicating divergent functional integration despite a shared degradation mechanism.
Gain and loss of gene function shaped the nickel hyperaccumulation trait in Noccaea caerulescens
Authors: Belloeil, C., Garcia de la Torre, V. S., Contreras Aguilera, R., Kupper, H., Lopez-Roques, C., Iampetro, C., Vandecasteele, C., Klopp, C., Launay-Avon, A., Leemhuis, W., Yamjabok, J., van den Heuvel, J., Aarts, M. G. M., Quintela Sabaris, C., Thomine, S., MERLOT, S.
The study presents a high-quality genome assembly for the nickel hyperaccumulator Noccaea caerulescens and uses it as a reference for comparative transcriptomic analyses across different N. caerulescens accessions and the non‑accumulating relative Microthlaspi perfoliatum. It identifies a limited set of metal transporters (NcHMA3, NcHMA4, NcIREG2, and NcIRT1) whose elevated expression correlates with hyperaccumulation, and demonstrates that frameshift mutations in NcIRT1 can abolish the trait, indicating an ancient, transporter‑driven origin of nickel hyperaccumulation.
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.
Arabidopsis lines with modified ascorbate concentrations reveal a link between ascorbate and auxin biosynthesis
Authors: Fenech, M., Zulian, V., Moya-Cuevas, J., Arnaud, D., Morilla, I., Smirnoff, N., Botella, M. A., Stepanova, A. N., Alonso, J. M., Martin-Pizarro, C., Amorim-Silva, V.
The study used Arabidopsis thaliana mutants with low (vtc2, vtc4) and high (vtc2/OE-VTC2) ascorbate levels to examine how ascorbate concentration affects gene expression and cellular homeostasis. Transcriptomic analysis revealed that altered ascorbate levels modulate defense and stress pathways, and that TAA1/TAR2‑mediated auxin biosynthesis is required for coping with elevated ascorbate in a light‑dependent manner.
Modulation of the GT Family 47 clade B gene affects arabinan deposition in elaters of Marchantia polymorpha
Authors: Kang, H. S. F., Lampugnani, E. R., Tong, X., Prabhakar, P. K., Flores-Sandoval, E., Hansen, J., Jorgensen, B., Bowman, J. L., Urbanowicz, B. R., Ebert, B., Persson, S.
The study investigates the function of two GT47B arabinan arabinosyltransferases in the liverwort Marchantia polymorpha, generating loss‑of‑function and overexpression lines to assess cell wall composition. Using CoMPP, glycosyl linkage analysis, and LM6 immunolabelling, the authors found that MpARADL2 mutants have reduced 1,5‑L‑arabinan epitopes in elaters despite unchanged overall 5‑linked Araf levels, suggesting additional enzymes compensate in thallus tissue. Attempts to express and purify the enzymes in HEK293 cells failed, implying a clade‑specific solubility requirement and highlighting the need to identify interacting partners.