Authors: Orosz, J., Lin, E. X., Torres Ascurra, Y. C., Kappes, M., Lindsay, P. L., Bashyal, S., Everett, H., Gautam, C. K., Jackson, D., Mueller, L. M.
The study identifies the pseudokinase CRN in Medicago truncatula as a regulator of inflorescence meristem branching and a negative modulator of root interactions with arbuscular mycorrhizal (AM) fungi, operating partially independently of the AM autoregulation CLE peptide MtCLE53. Transcriptomic profiling of crn mutant roots reveals disruptions in nutrient, symbiosis, and stress signaling pathways, highlighting the multifaceted role of MtCRN in plant development and environmental interactions.
The study examined how varying temperature regimes, including cold deprivation and early cold exposure, affect dormancy onset and maintenance in sweet cherry (Prunus avium) flower buds. Phenological monitoring combined with transcriptomic analyses revealed that temperature drives dormancy progression, identifying specific genes and pathways responsive to cold, and uncovering a distinct shallow dormancy phase induced by cold deprivation with a unique molecular signature.
The study combined cell biology, transcriptomics, and ionomics to reveal that zinc deficiency reduces root apical meristem size while preserving meristematic activity and local Zn levels, leading to enhanced cell elongation and differentiation in Arabidopsis thaliana. ZIP12 was identified as a highly induced gene in the zinc‑deficient root tip, and zip12 mutants displayed impaired root growth, altered RAM structure, disrupted Zn‑responsive gene expression, and abnormal metal partitioning, highlighting ZIP12’s role in maintaining Zn homeostasis and meristem function.
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.
Metagenomic pool sequencing of infected maize leaves was used to monitor the population dynamics of the fungal pathogen Exserohilum turcicum, revealing a recent shift from local clonal lineages to tropical Kenyan lineages in a Swiss agricultural region. The novel leaf‑pooling approach enabled cost‑effective, large‑scale sampling, while phyllobiome analyses showed consistent microbial communities across maize varieties.
Gene regulatory network analysis of somatic embryogenesis identifies morphogenic genes that increase maize transformation frequency
Authors: Renema, J., Luckicheva, S., Verwaerde, I., Aesaert, S., Coussens, G., De Block, J., Grones, C., Eekhout, T., De Rybel, B., Brew-Appiah, R. A. T., Bagley, C. A., Hoengenaert, L., Vandepoele, K., Pauwels, L.
The study co‑expressed BABY BOOM and WUSCHEL2 in maize embryos and used single‑cell transcriptomics to infer cell‑type‑specific gene regulatory networks underlying induced somatic embryogenesis. By prioritizing and functionally validating four novel transcription factors, the authors enhanced maize transformation efficiency and produced fertile transgenic plants.
The study tracked molecular changes in plastoglobules and thylakoids of Zea mays B73 during heat stress and recovery, revealing increased plastoglobule size, number, and adjacent lipid droplets over time. Proteomic and lipidomic analyses uncovered up‑regulation of specific plastoglobule proteins and alterations in triacylglycerol, plastoquinone derivatives, and phytol esters, suggesting roles in membrane remodeling and oxidative defense. These insights highlight plastoglobule‑associated pathways as potential targets for enhancing heat resilience in maize.
The study quantifies de novo insertions of the maize Mutator (Mu) transposon across four tissue types, achieving detection of mutations at a frequency of 1 in 16,000. While allele frequency distributions are reproducible within a tissue, they differ markedly between tissues, with roots showing few high-frequency insertions and endosperm displaying many low-frequency ones. Reanalysis of pollen data suggests that observed late Mu activity is better explained by cell division dynamics rather than ongoing transposition.
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 validates and quantifies biological nitrogen fixation in Mexican maize varieties and assesses a double‑haploid population derived from an elite inbred (PHZ51) crossed with these landraces. Aerial root traits show moderate to high heritability, and QTL mapping reveals multiple loci influencing root number, node occurrence, and diameter, with most favorable alleles originating from the landraces. The authors suggest that pyramiding the identified QTL into elite germplasm could enhance maize’s BNF capacity, pending field validation.